PREVENTION IN CHILDREN UNDER FIVE YEARS IN KISUMU DISTRICT, KENYA. PHILIMON MAJWA OMONDI BSC (CHEMISTRY)

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1 EFFECTIVENESS OF PERMANET 2.0 AND OLYSET FOR MALARIA PREVENTION IN CHILDREN UNDER FIVE YEARS IN KISUMU DISTRICT, KENYA. PHILIMON MAJWA OMONDI BSC (CHEMISTRY) A THESIS SUBMITTED IN PARTIAL FULFILLMENT FOR THE DEGREE OF MASTER OF PUBLIC HEALTH IN THE SCHOOL OF HEALTH SCIENCES OF KENYATTA UNIVERSITY. SEPTEMBER 2010.

2 DECLARATION This thesis is my original work and has not been presented for a degree in any other university. Philimon Majwa Omondi, I57/OL/12707/04, Department of Public Health. ii Signed Date This thesis has been submitted for examination with our approval as university supervisors. DR. NICHOLAS K. GIKONYO, Department of Pharmacy and Complementary/Alternative Medicine, Kenyatta University. Signed: Date: PROF. JOHN HENRY OUMA, Department of Public Health, Kenyatta University. Signed: Date:

3 iii DEDICATION This work is dedicated to my late mother Fridah Majwa, to my father Melkizadek Majwa, to my siblings Ezekiel Otieno, Joshua Odhiambo, Nashon Oluoch, Nathan Ouma, Loise Atieno and to Annette Fridah and Mercy Kyndya.

4 iv ACKNOWLEDGEMENT I wish to express my sincere gratitude to all the individuals who through their support contributed to the successful completion of this research work. I am deeply indebted to my supervisors Dr. Nicholas Gikonyo and Prof. John Henry Ouma for their expert guidance and support during this work. Sincerely thanks to Mr. Oguya of the department of Public Health, Kenyatta University for his assistance in data analysis. Heartfelt appreciation to Mr. George Olang, CDC/KEMRI Kisian, Kisumu for the support he gave me during laboratory bioassay of the LLINs and his patience, understanding and encouragement during the research work. Thanks to Mr. Enos Kassam, Mr. Zachary Abok and Miss Elizabeth Okinda of Kenya Red Cross Society Kisumu Branch for the invaluable services they offered during field logistics and data collection. Thanks to the community leaders of Kadibo Division for their positive contributions and critique on the subject of my research without which I could not have accomplished my objective. Last but not least I thank the Almighty God for granting me all the achievements and His grace all through the study.

5 v ABSTRACT Globally, there are an estimated 247 million malaria cases and 3.3 billion people at risk. In Kenya an estimated 11.3 million malaria cases have been reported with 27,000 deaths due to malaria. Long-lasting insecticidal nets (LLINs) are advocated by World Health Organisation (WHO) for protection against malaria. In Kenya the National Malaria Control Programme (NMCP) distributed 7.1 million insecticide treated nets (ITNs) in 2006, of which 6.3 million were LLINs. Within Kisumu district, the proportion of children under 5 years who benefited from this campaign increased from 24% in 2006 to 65% in Paradoxically however, the malaria incidence within children under 5 years increased from 162,000 in 2006 to 184,000 in The objective of the study was therefore to determine whether socio-cultural factors reduces the effectiveness of the PermaNet 2.0 and Olyset as interventions in controlling malaria within children under 5 years in Kadibo division, Kisumu district. A questionnaire was administered to 306 respondents in Kadibo Division. From the respondents who were interviewed 47% had one net, 29% had two, 14% had three and 5% had four ( 2 =2.433, p 0.876). Most of the nets (54%) were obtained from the Health facilities, while 46% were bought from shops, chemist and market places. Furthermore, 68% of the freely distributed nets from health facilities were of PermaNet 2.0 brand while 32% were of Olyset brand. A good proportion of the respondent (93%) confirmed that they had used nets the previous night ( 2 =1.686, p 0.430). Only 12% of the households had nets with no holes. Most households (63%) reported having nets with between 1-5 holes while 25% reporting had nets with 6-45 holes. During the period of the use of the net, 70% of children sleeping under it reported contracting malaria in the previous six months compared to 30% who had not contracted malaria. Out of the children who had contracted malaria, 12% had suffered from malaria once, 36% had suffered from malaria twice and 31% had suffered from malaria more than thrice while 21% had not contracted malaria. The proportion of sleeping rooms exposed to heat and smoke from cooking area was 70%. Thus, the heat generated by the hearth and the adsorbed smoke particles on the net is suspected to affect the effectiveness of the LLINs. Most of the respondents preferred green and blue oval shaped nets while the white ones were reserved for guests, funerals and wedding gowns. Majority of respondents adhered to the requirement that the nets should be washed at most 10 times within 2 years of use. In this study, 75% of the respondents washed the nets 5 times within the two years of use. Samples of Olyset and PermaNet 2.0 nets, which had been in use in Kadibo villages for 2 years ( 2 =2.708, p 0.439), were tested in laboratory bioassay for their vector knockdown capacities (KD) against Anopheles gambiae mosquitoes. An ideal LLIN should have an 80% mosquito knockdown for KD3, KD60 and KD24, however the results of this study showed that PermaNet 2.0 had KD3 7%, KD60 7.9% and KD %. Olyset net had KD3 4.1%, KD60 6.7% and KD24 8.7% thus it is evident that PermaNet 2.0 though with a dismal performance is more effective than Olyset ( 2 =10.083, p 0.040). The results suggest on one hand, that the PermaNet 2.0 and Olyset do not contain sufficient insecticide to knockdown mosquitoes and on the other hand, that the mosquitoes may have developed resistance to the insecticide. These results show that the PermaNet 2.0 and Olyset in Kadibo division are not effective against the prevention of malaria to children under 5 years after 2 years of use. This study recommends that the National Malaria Control Programme should check the compliance of the PermaNet 2.0 and Olyset at source for quality.

6 vi ACRONYMS AND ABBREVIATIONS ACT Artemisine-based combined therapy ANOVA Analysis of Variance BC Before Christ BCE Before Christ Era CDC Center for Diseases Control CE Christ Era CSP Circumsporozoite Surface Protein DDT Dichloro-diphenyl-tricloroethane DEET Diethyltoluamide DHS Demographic Health Survey ELISA Enzyme-linked immunosorbent assay GST Glutathione S-transferases (GST). IFA Immunofluorescence Assay IPT Intermittent Preventive Treatment IRS Indoor Residual Spraying ITNs Insecticides Treated Nets KD3 Knock down mortality of mosquito scores at 3 minutes KD 60 Knock down mortality of mosquito scores at 1 hour (60 minutes) KD24 Knock down mortality of mosquito scores at 24 hours Kdr Knock Down Resistance gene KEMRI Kenya Medical Research Institute LLlNs Long Lasting Insecticides Nets LSA- 1 Liver Stage Antigen -1 MCH Maternal and Child Health Services MDGs Millennium Development Goals MOH Ministry of Health MSP- 1 Merozoites Surface Protein -1 MTKD Median Time in seconds for Knocked Down of mosquitoes PCR Polymerase Chain Reaction PT Permethrin Tolerance RBM Roll Back Malaria

7 RDT ROK SD SPSS UNICEF WHO WHOPES WPRO vii Rapid Diagnostic Tests Republic Of Kenya Standard deviation Statistical Package for Social Sciences. United Nation's Children Emergency Funds World Health Organization World Health Organization Pesticides Evaluation Scheme Western Pacific Regional Office

8 viii TABLE OF CONTENTS DECLARATION... ii DEDICATION... iii ACKNOWLEDGEMENT... iv ABSTRACT... v ACRONYMS AND ABBREVIATIONS... vi TABLE OF CONTENTS.... viii LIST OF TABLES.... xi LIST OF FIGURES.... xii LIST OF PLATES.... xiii CHAPTER ONE : INTRODUCTION Background Problem statement Justification Research questions Hypothesis Broad objectives Specific objectives CHAPTER TWO : LITERATURE RERVIEW History of malaria Ancient history (2700 BCE-340 CE) Discovery of the malaria parasite (1880) Life cycle of malaria parasites Malaria as a disease Malaria relapses Malaria parasite diagnosis Clinical diagnosis Microscopic diagnosis Rapid Diagnostic Test Molecular diagnosis Serology Epidemiology of malaria in Kenya Malaria endemicity in Kenya Malaria control

9 ix Global malaria control strategy Roll back malaria The Abuja declaration and plan of action Kenya National Malaria Strategy ( ) Vector control Insecticide-Treated Bed Nets Mosquito behavioral effects towards pyrethroids Resistance effects of pyrethroids Immunity status and rebound of morbidity and mortality Evolution of Long-Lasting Insecticide-treated Nets (LLINs) Olyset PermaNet Indoor Residual Spraying Larval Control Fogging or area spraying Personal protection measures Economic costs of malaria CHAPTER THREE: MATERIALS AND METHODS Research Design Study area Target population Sample size estimate Data collection Sampling of the bednets Data collection tools Focus Group Discussions (FGD) Key Informant Interview guides Inclusion Criteria Exclusion criteria Logistical and ethical consideration Laboratory Bioassay Procedure for rearing mosquito Introducing the mosquitoes for bioassay

10 x 3.7 Data management and analysis CHAPTER FOUR: RESULTS AND DISCUSSION Household characteristics Objective 1: Proportion of families with children under 5 years using PermaNet 2.0 to Olyset in Kadibo division Number of sleeping areas in the house Number of long lasting insecticide treated nets in the house Child under 5 years sleeping under the long lasting insecticide treated nets the previous night Sleeping time for the child under 5 years Objective 2: Cultural perception which hinders or promotes the use of PermaNet 2.0 and Olyset nets within households having children less than 5 years in Kadibo Number of times the long lasting insecticide treated nets had been washed Number of holes in the long lasting insecticide treated nets Prefered shape of the long lasting insecticide treated nets Preferred color of the long lasting insecticide treated nets Preferred method of preventing malaria People having contracted malaria while using a long lasting insecticide treated net Objective 3: Household practices affect the mosquito knockdown of PermaNet 2.0 and Olyset nets sampled from household in Kadibo division Laboratory bioassay results Objective 4: Accessibility and affordability of PermaNet 2.0 and Olyset nets within households in Kadibo division CHAPTER FIVE : CONCLUSIONS AND RECCOMENDATIONS CONCLUSIONS RECOMMENDATIONS SUGGESTION FOR FURTHER RESEARCH REFERENCES ANNEX 1: CONSENT FORM ANNEX 2 : HOUSEHOLD QUESTIONNAIRE ANNEX 3: HEALTH FACILITY QUESTIONNAIRE ANNEX 4: OBSERVATION CHECKLIST ANNEX 5: FOCUSED GROUP DISCUSSION CHECKLIST... 99

11 xi LIST OF TABLES Table 1: Population in Kadibo Division Table 2: Number of sampled households from each location in Kadibo Division Table 3 Distribution of the sleeping areas for children under 5 years Table 4 Long lasting insecticide treated nets in the respondent house Table 5: The usage of the long lasting insecticide treated nets last night Table 6: The number of the holes on the long lasting insecticide treated nets Table 7: The preferred shape of the long lasting insecticide treated nets Table 8: Color of long lasting insecticide treated nets preferred by respondents Table 9: Results for the Bioassay for the PermaNet Table 10: Results for the Bioassay for the Olyset Table 11: Results for the Bioassay for the SupaNet Table 12: Knock Down after 3min chi-square analysis Table 13: Knockdown after 60mins chi-square analysis Table 14: Knock down after 24hrs Chi-square analysis Table 15: Presentation of where the respondent obtained the bednet Table 16: A comparison of the prices of the Bednets Table 17: The year of acquisition of the net

12 xii LIST OF FIGURES Figure 1: Proportion of children sleeping under LLINs between Figure 2: Reported malaria cases in Kisumu District... 5 Figure 3: The life cycle of plasmodium species Figure 4: Estimated deaths from malaria per 1000 population in Figure 5: Eighteen countries estimated to have 90% malaria deaths Figure 6: Malaria endemicity in Kenya Figure 7: Map of the study area Figure 8: Age of the respondents Figure 9: The number of sleeping areas in the respondents' house Figure 10: Whether a child slept under a long lasting insecticide treated nets Figure 11: The time when children under 5 years slept Figure 12: Long lasting insecticide treated nets has been washed Figure 13: Long lasting insecticide treated nets was washed without insecticide Figure 14: Long lasting insecticide treated nets was soaked in insecticide Figure 15: Response on how to prevent malaria Figure 16: Long lasting insecticide treated net users having contracted malaria Figure 17: Episodes of malaria within child under 5 years using the LLINs Figure 18: Knowledge of the respondent on symptoms of malaria Figure 19: Response on how malaria is transmitted Figure 20: Respondent answer on the treatment of malaria Figure 21: Respondents' perception on the price of the LLINs

13 xiii LIST OF PLATES Plate 1: Fishermen along the beach of Lake Victoria using LLINs for fishing Plate 2: LLINs being prepared for overnight fishing Plate 3: Demonstration of IRS Plate 4: A pond which is a potential breeding site for mosquito larvae Plate 5: A fogging machine spraying insecticide for malaria control Plate 6: Sampled nets from the households Plate 7: Insertion of the WHO cones for the bioassays Plate 8: Mosquitoes inside the control net Plate 9: Aspirator used in introducing the mosquitoes in the cones Plate 10: 4-5 day old mosquitoes used in the experiment

14 1 CHAPTER ONE INTRODUCTION 1.1 Background Malaria is a major public health problem in terms of morbidity and mortality, especially in Sub-Saharan Africa where it is estimated that about 400 million clinical cases of malaria, about 80% of the world's total, are recorded each year (WHO, 2008). Some of these cases are severe forms of malaria from which 20% of the sufferers die due to improper management. In malaria endemic countries, mainly in Africa, 20-40% of all outpatient visits and 20-50% of hospital admissions are due to malaria (WHO and UNICEF, 2005). Malaria affects the economy of countries, societies and households considerably. Moreover it is estimated that more than 20% of disposable income of households in malaria endemic areas is spent on ineffective methods for malaria treatment and prevention every year (Magoma et al, 2006). Despite much effort in Africa to contain the problem of malaria the results have not been encouraging and the burden of malaria in Sub Saharan Africa countries remains intolerable. Currently chemoprophylaxis and chemotherapeutic drug administration play a major role in malaria prevention and control. However, whilst 70-80% of malaria cases are managed at household level, many households are ignorant of proper case management (WHO, 2005). Treatment of malaria cases alone without vector control will not control the incidence of new infections, even in the short term (Magoma et al, 2006). Although there have been many anti-malaria campaigns in Africa and other parts of the world, it remains the most important vector-borne disease. Mortality and morbidity from this disease have been reduced in countries such as the United States, Europe, and China, but in tropical Africa there has been no reduction.

15 2 Malaria is the leading cause of morbidity and mortality in Kenya. It accounts for about 30% of all outpatient consultations, 19% of all hospital admissions, and is reported to cause approximately 27,000 deaths annually among children under-five years of age. Among the different malaria epidemiological zones found in Kenya, there are 30 malaria-endemic districts that experience stable, year-round malaria transmission with two peak transmission periods (June-August, and late November). An additional 16 districts in Kenya remain at-risk for periodic malaria epidemics. The total population at risk of malaria is approximately 23 million, or 70% of the population, including an estimated 3,500,000 children under-five and 1,100,000 pregnant women (WHO Malaria report, 2008). According to the 2007 Malaria Indicator Survey (MIS), the proportion of households with at least one Insecticide Treated Net (ITN) increased from 6% in the 2003 Demographic Health Survey (DHS) to 49% in the 2007 Malaria Indicator Survey (MIS). The proportion of children under-five sleeping under an Insecticide Treated Net (ITN) the previous night also increased from 5% in the 2003 Demographic Health Survey (DHS) to 40% in the 2007 Malaria Indicator Survey (MIS), the proportion of pregnant women who received two or more doses of Sulfadoxine Pyrimethamine (SP) during their last pregnancy increased from 4% to 12.3% over the same period. With the introduction of Artemisine-based combined therapy (ACT) as the first-line treatment in September 2006, the 2007 Malaria Indicator Survey (MIS) found that 4.3% of children under-five received Artemisine-based combined therapy (ACT) treatment within 24 hours of the onset of a fever experienced during the two weeks prior to the survey.

16 3 The Government of Kenya subscribes to the Roll Back Malaria Abuja targets and the Millennium Development Goals. Malaria is considered a priority for poverty reduction and the government s development agenda. Although the Ministry of Health (MOH) is committed to increasing access to health services and increasing the efficiency and quality of those services nationwide, a weak health infrastructure and shortage of health workers are formidable obstacles (National Malaria Control Programme, 2009). The health burden of malaria is immense. Malaria-related illness kills at least one million people each year, and most of these deaths are among African children. Insecticide- Treated bed nets (ITNs) are amongst the most effective tools for reducing malaria transmission and mortality. A series of trials in Africa have shown that proper mosquito net use reduces malaria incidence among children by anywhere from 14 to 63 per cent (Lenger et al 2004). With ITN use, all cause-mortality in children has been shown to decline by 25 per cent in Gambia, 33 per cent in Kenya (Magoma et al, 2006) and 17 per cent in Ghana (Magoma et al, 2006). Based on findings such as these, the promotion of ITN use has become a central element of national and international efforts against malaria. While the evidence base on the effectiveness of ITNs in reducing malaria transmission has grown rapidly in recent years, utilization rates for ITNs in most African countries have not. In most malaria endemic regions, fewer than 10 per cent of children or pregnant women regularly sleep under ITNs. The African summit on Roll Back Malaria, Abuja, Nigeria, April 2000) set an ambitious target for expanding ITN use in Africa at least 60% coverage of high-risk groups by the year Achieving this goal was to require massive increase in ITN acquisition and targeting those most at risk under-fives and pregnant women.

17 4 1.2 Problem statement As figure 1 illustrates, the National Malaria Control Programme distributed 7.1 million ITNs in 2006, of which 6.3 million were long lasting Insecticide treated nest (LLINs). The proportion of children under 5 years who benefited from this distribution increased from 24% in 2006 to 65% in Figure 2 however, illustrates that malaria trend in Kisumu district increased from 162,000 in 2006 to 184,000 in Thus the question of whether the intervention methods using long lasting insecticide treated nets (LLINs) were really effective in reducing the malaria incidences. Proportion of Children under 5 yrs sleeping under LLINs (%) Year Figure 1: Proportion of children sleeping under LLINs between , (National malaria control programme, 2008)

18 Number of Malaria cases in Kisumu malaria cases Year Figure 2: Reported malaria cases in Kisumu District (Kisumu district annual report, 2008) According the Ministry of Public Health and Sanitation, there is evidence of people turning the LLINs into fishing gear especially in Kisumu District and also in the Lake Victoria region. Moreover it has been reported that Long lasting insecticide treated nets (LLINs) are also used to make wedding dresses (Daily Nation 22 nd April 2009) thus compounding the malaria situation further. Other socio-cultural and socio-economic practices of the community may have seriously undermined the efforts of malaria control using long lasting insecticide treated nets. 1.3 Justification With more than 70% of the Kenya s population living in areas where malaria is transmitted, malaria is the leading cause of morbidity and mortality in Kenya. Malaria is responsible for approximately 30% of out-patient visits requiring more than eight million out-patient treatments at health facilities each year, and 19% of all hospital admissions. Children under-five are particularly vulnerable. About 3.5 million children are at risk of infection and developing severe malaria, which not only affects child survival, but may also delay educational and social development. At least 14,000 children are hospitalized

19 6 annually for malaria, and there are an estimated 27,000 deaths among children under-five each year. Pregnant women are also at high risk, and there are approximately 1.1 million pregnancies per year in malaria endemic areas. During pregnancy, malaria causes anemia, miscarriages and can result in low birth weight infants. Each year, an estimated 6,000 pregnant women suffer from malaria-associated anemia, and four thousand babies are born with low birth weight as a result of maternal anemia. Economically, it is estimated that 170 million working days are lost each year because of malaria illness. The fulfilment of vision 2030, Millennium Development goals DGS in reducing the mortality and morbidity due to malaria for children less than 5 years depends on the use of the most effective and culturally acceptable method at the community level. Results of this study will give a good suggestion for policy formulation in public health early warning mechanism for malaria and make a recommendation whether there should be a change of the mode of delivery for the LLINs and more specifically the need to involve the community members in designing and formulating these policies. 1.4 Research questions 1. What is the relationship between the proportion of families with children under 5 years using PermaNet 2.0 to Olyset in Kadibo Division and the malaria cases? 2. What are the cultural perceptions which hinder or promote the use of PermaNet 2.0 and Olyset nets within households having children less than 5 years in Kadibo Division. 3. Does PermaNet 2.0 and Olyset nets used in household in Kadibo Division have the ability to knock down mosquitoes in a laboratory experiment. 4. How is the accessibility and affordability of PermaNet 2.0 and Olyset nets to households in Kadibo Division.

20 7 1.5 Hypothesis The effectiveness of PermaNet 2.0 and Olyset nets as intervention in controlling malaria in children less than five years is not affected by socio-cultural factors of the community. 1.6 Broad objectives To determine whether socio-cultural factors affect the effectiveness of PermaNet 2.0 and Olyset as interventions in controlling malaria within children under 5 years in Kadibo division. 1.7 Specific objectives 1. To find out the proportion of families with children under 5 years using PermaNet 2.0 to Olyset in Kadibo division. 2. To find out the cultural perception which hinder or promote the use of PermaNet 2.0 and Olyset nets within households having children less than 5 years in Kadibo division. 3. To find out if household practices affect the mosquito knockdown of PermaNet 2.0 and Olyset nets sampled from household in Kadibo division. 4. To know the accessibility and affordability of PermaNet 2.0 and Olyset nets within households in Kadibo division.

21 8 CHAPTER TWO LITERATURE RERVIEW 2.1 History of malaria According to Center of Disease Control (CDC), Malaria or a disease resembling malaria has been noted for more than 4,000 years. From the Italian word for "bad air," mal'aria has influenced to a great extent human populations and human history. 2.2 Ancient history (2700 BCE-340 CE) The symptoms of malaria were described in ancient Chinese medical writings. In 2700 BC, several characteristic symptoms of what would later be named malaria were described in the Nei Ching, the Canon of Medicine. Nei Ching was edited by Emperor Huang Ti. Malaria became widely recognized in Greece by the 4th century BCE, and it was responsible for the decline of many of the city-state populations. Hippocrates noted the principal symptoms. By the era of Pericles, there were extensive references to malaria in the literature and depopulation of rural areas was recorded. In the Susruta, a Sanskrit medical treatise, the symptoms of malarial fever were described and attributed to the bites of certain insects. A number of Roman writers attributed malarial diseases to the swamps. In China, during the second century BCE, the Qinghao plant (Artemisia annua L) was described in the medical treatise, 52 Remedies, found in the Mawangdui Tomb. 2.3 Discovery of the malaria parasite (1880) Charles Louis Alphonse Laveran, a French army surgeon stationed in Constantine, Algeria, was the first to notice parasites in the blood of a patient suffering from malaria. This occurred on the 6th of November For his discovery, Laveran was awarded the Nobel Prize in 1907.

22 9 2.4 Life cycle of malaria parasites In nature, malaria parasites spread by infecting successively two types of hosts: humans and female Anopheles mosquitoes (Figure 3). In humans, the parasites grow and multiply first in the liver cells and then in the red cells of the blood. In the blood, successive broods of parasites grow inside the red cells and destroy them, releasing daughter parasites ("merozoites") that continue the cycle by invading other red cells. The blood stage parasites are those that cause the symptoms of malaria. When certain forms of blood stage parasites ("gametocytes") are picked up by a female Anopheles mosquito during a blood meal, they start another, different cycle of growth and multiplication in the mosquito. After days, the parasites are found (as "sporozoites") in the mosquito's salivary glands. When the Anopheles mosquito takes a blood meal on another human, the sporozoites are injected with the mosquito's saliva and start another human infection when they parasitize the liver cells. Thus the mosquito carries the disease from one human to another (acting as a "vector"). Differently from the human host, the mosquito vector does not suffer from the presence of the parasites. 2.5 Malaria as a disease Infection with malaria parasites may result in a wide variety of symptoms, ranging from absent or very mild symptoms to severe disease and even death. Malaria disease can be categorized as uncomplicated or severe (complicated). In general, malaria is a curable disease if diagnosed and treated promptly and correctly. Following the infective bite by the Anopheles mosquito, a period of time (the "incubation period") goes by before the first symptoms appear. The incubation period in most cases varies from 7 to 30 days. The shorter periods are observed most frequently with Plasmodium falciparum and the longer ones with Plasmodium malariae.

23 10 Figure 3: The life cycle of plasmodium species ( ) The classical (but rarely observed) malaria attack lasts 6-10 hours. It consists of: a cold stage (sensation of cold, shivering); a hot stage (fever, headaches, vomiting; seizures in young children) and finally a sweating stage (sweats, return to normal temperature, tiredness).

24 11 Classically (but infrequently observed) the attacks occur every second day with the "tertian" parasites. Severe malaria occurs when P. falciparum infections are complicated by serious organ failures or abnormalities in the patient's blood or metabolism. The manifestations of severe malaria include: cerebral malaria, with abnormal behavior, impairment of consciousness, seizures, coma, or other neurologic abnormalities; severe anemia due to hemolysis (destruction of the red blood cells); hemoglobinuria (hemoglobin in the urine) due to hemolysis; pulmonary edema (fluid buildup in the lungs) or acute respiratory distress syndrome, which may occur even after the parasite counts have decreased in response to treatment; abnormalities in blood coagulation and thrombocytopenia (decrease in blood platelets); cardiovascular collapse and shock. Other manifestations that are of concern are: acute kidney failure; hyperparasitemia, where more than 5% of the red blood cells are infected by malaria parasites. Metabolic acidosis (excessive acidity in the blood and tissue fluids), often in association with hypoglycemia (low blood glucose). Hypoglycaemia may also occur in pregnant women with uncomplicated malaria, or after treatment with quinine. 2.6 Malaria relapses In P. vivax and P. ovale infections, patients having recovered from the first episode of illness may suffer several additional attacks ("relapses") after months or even years without symptoms. Relapses occur because P. vivax and P. ovale have dormant liver stage parasites ("hypnozoites") that may reactivate.

25 2.7 Malaria parasite diagnosis Clinical diagnosis Clinical diagnosis is based on the patient's symptoms and on physical findings at examination. The first symptoms of malaria (most often fever, chills, sweats, headaches, muscle pains, nausea and vomiting) are often not specific and are also found in other diseases (such as the influenza and common viral infections). Likewise, the physical findings are often not specific (elevated temperature, perspiration, tiredness). In severe malaria (caused by P. falciparum), clinical findings (confusion, coma, neurologic focal signs, severe anemia, respiratory difficulties) are more striking and may increase the suspicion index for malaria. Thus, in most cases the early clinical findings in malaria are not typical and need to be confirmed by a laboratory test Microscopic diagnosis Malaria parasites can be identified by examining under the microscope a drop of the patient's blood, spread out as a "blood smear" on a microscope slide. Prior to examination, the specimen is stained to give to the parasites a distinctive appearance. This technique remains the gold standard for laboratory confirmation of malaria. However, it depends on the quality of the reagents, of the microscope, and on the experience of the laboratory analyst Rapid Diagnostic Test Various test kits are available to detect antigens derived from malaria parasites. Such immunologic ("immunochromatographic") tests most often use a dipstick or cassette format, and provide results in 2-15 minutes. These "Rapid Diagnostic Tests" (RDTs) offer a useful alternative to microscopy in situations where reliable microscopic diagnosis

26 13 is not available. Malaria RDTs are currently used in some clinical settings and programs. However, before malaria RDTs can be widely adopted, several issues remain to be addressed, including improving their accuracy; lowering their cost; and ensuring their adequate performance under adverse field conditions Molecular diagnosis Parasite nucleic acids are detected using polymerase chain reaction (PCR). This technique is more accurate than microscopy. However, it is expensive, and requires a specialized laboratory (even though technical advances will likely result in field-operated PCR machines Serology Serology detects antibodies against malaria parasites, using either indirect immunofluorescence assay (IFA) or enzyme-linked immunosorbent assay (ELISA). Serology does not detect current infection but rather measures past experience Drug Resistance tests Drug resistance tests are performed in specialized laboratories to assess the susceptibility to antimalarial compounds of parasites collected from a specific patient. Two main laboratory methods are available: In vitro tests: The parasites are grown in culture in the presence of increasing concentrations of drugs; the drug concentration that inhibits parasite growth is used as endpoint. Molecular characterization: molecular markers assessed by PCR or gene sequencing allow also the prediction, to some degree, of resistance to some drugs; however, the predictive values of these molecular tests are still being evaluated.

27 Geographic distribution of malaria Where malaria is found depends mainly on climatic factors such as temperature, humidity, and rainfalls. Malaria is transmitted in tropical and subtropical areas, where: Anopheles mosquitoes can survive and multiply; Malaria parasites can complete their growth cycle in the mosquitoes ("extrinsic incubation period"). Temperature is particularly critical. For example, at temperatures below 20 C (68 F), P. falciparum (which causes severe malaria) cannot complete its growth cycle in the Anopheles mosquito, and thus cannot be transmitted. Even within tropical and subtropical areas, transmission will not occur: at high altitudes during cooler seasons in some areas in deserts (excluding the oases) in some islands in the Pacific Ocean, which have no local Anopheles species capable of transmitting malaria in some countries where transmission has been interrupted through successful eradication. Generally, in warmer regions closer to the equator: transmission will be more intense malaria is transmitted year-round P. falciparum predominates. The highest transmission is found in Africa South of the Sahara as illustrated in figure 4 and figure 5 below.

28 15 Figure 4: Estimated deaths from malaria per 1000 population in 2006 (World malaria report 2008, WHO). Figure 5: Eighteen countries estimated to have 90% malaria deaths in the Africa region in 2006 (World malaria report 2008, WHO). 2.9 Epidemiology of malaria in Kenya Malaria is the leading cause of morbidity and mortality in Kenya, accounting for 30% of all out-patient attendance in the country's health facilities and 20% of in-patient admissions

29 16 (Kenya Ministry of Health, 2006). However, the distribution of malaria is not uniform, due to geographical differences in altitude, rainfall and humidity. These geographical factors influence the transmission patterns as they determine the vector densities and intensity of biting. The higher the ambient temperature, the shorter the sporogonic cycle of the parasite in the mosquito, hence the shorter the duration of the gonotrophic cycle. The risks of an individual acquiring a malaria infection are governed by the chances that he/she will come into contact with one of the principal mosquito vectors (A. gambiae s.1 or A. funestus) and that these vectors carry the malaria parasite P. falciparum Malaria endemicity in Kenya Malaria transmission is common every year, immunity is acquired by the community before adulthood and the risks of disease and death from malaria are concentrated amongst children and pregnant women. These areas can show marked seasonality in transmission co-incidental with the rains. There is little variation between years in the burden of malaria. The level of endemicity of malaria in Kenya varies from region to region and there is a big diversity in risk of malaria infection largely driven by climate and temperature which includes the effects of altitude as outlined in Figure 6 below. Based on malaria risk, districts in Kenya are categorized into one of five classes of ecology. Lakeside endemic districts close to lake Victoria where transmission is throughout the year. Coastal endemic - similar to lakeshore in endemicity. However, transmission and maximal disease risk period exhibit stronger seasonality and the intensity of transmission are lower toward the Somali border. Highland - The parasite prevalence is low in the highland districts. A common feature

30 17 of malaria here is that while there is always a potential for limited transmission lending itself to an overall low disease risk on an average year, variations in rainfall and ambient temperatures between years can lead to epidemics affecting all members of the community. Arid seasonal- Several districts in a large part of North eastern, north western areas only experience malaria where communities live near water. Arid and rainfall limited effects upon transmission lend the transmission of parasites to a few months of the.overall, all districts in this category will support low infection prevalence rates in childhood. Low malaria risk- these areas cover highlands within Central Province and Nairobi province. Several areas experience almost no malaria risk e.g. Nairobi, Nyeri, Nakuru.

31 18 Figure 6: Malaria endemicity in Kenya (National Malaria Control Programme, 2009) 2.10 Malaria control In 1995 the world health assembly endorsed a concept paper on worldwide eradication of malaria. The magnitude of the malaria situation in Africa is affected by a variety of factors, none of which addressed alone is likely to provide a sustainable solution. The high vector population with its varied and partly unknown ecology and resistance to insecticides, the

32 19 diversity of the parasite ( Plasmodium falciparum, Plasmodium malariae, Plasmodium ovale, Plasmodium vivaxoccur) and its evolving resistance to drugs, the declining economy and low level of economic development, the relationship of malaria and other diseases and lastly the diverse cultural, social and environmental factors which affect acceptance and use of preventive and control measures collectively impact negatively on the malaria situation Global malaria control strategy The revised global malaria strategy was approved in Amsterdam in 1992 by the health ministers of several malaria prone countries; with the aim of reducing the disease burden at all level (World Health Organization, 2005). The overall goal of global malaria control is to prevent mortality and reduce morbidity and social economic losses through the progressive improvement and strengthening of local and national capacities. The four basic technical elements of the strategy are: to provide early diagnosis and prompt treatment to plan and implement selective and sustainable preventive measures, including vector control. to detect early, contain or prevent epidemics to strengthen local capacities in basic and applied research to permit and promote the regular assessment of a country s malaria situation, in particular the ecological, social and economical determinants of the disease. The 49 th session of the UN general assembly in 1994 endorsed the strategy on control of malaria and requested the WHO to develop an action plan for In 1997, the OAU states, now AU adopted the Harare declaration on malaria prevention and control and pledged to make malaria control a priority (WHO, 1993).

33 Roll back malaria Roll back malaria is a global partnership founded by governments of malaria- afflicted countries WHO, UNDP, UNICEF and World Bank. It was launched in 1998 (WHO-RBM, 2003). It offers a great opportunity for a joint action to tackle the threat of malaria for the world people by the year 2010 by saving lives, reducing poverty, boosting school attendance and making life better for millions of people living in poor countries, especially sub-saharan Africa. The key elements of the initiative were: effective management of malaria including malaria outbreaks rapid diagnosis and treatment of those who are infected by malaria multiple and cost effective means of preventing infections dynamic global partnership supported by a coalition of partners working within a common approach (WHO-RBM, 2003) The Abuja declaration and plan of action The African summit on roll back malaria was held in Abuja, Nigeria on the 25 th April Forty four representatives from the fifty malaria affected countries in Africa attended the summit. The summit concluded by endorsing Abuja the declaration and plan of action (WHO-RBM, 2003). Some of the Abuja targets were: to ensure that by year 2005 that at least 60% of those suffering from malaria have prompt access to affordable treatment within 24hr of the onset of the symptoms. at least 60% of those at risk of malaria particularly children under five years of age and

34 21 pregnant women, will benefit from the most suitable combination of personal and community protective measures such as ITNs and other intervention which are accessible and affordable to prevent infections and suffering at least 60% of all pregnant women who are at risk of malaria, especially those in the first pregnancies have access to chemoprophylaxis or intermittent presumptive treatment Kenya National Malaria Strategy ( ) The Kenya National Malaria Control Programme (NMCP) was launched in 1994 under the division of vector borne diseases. In 1998, roll back malaria movement that was started by the WHO, compelled the Kenya Ministry of Health (MOH) to formulate the National Malaria Strategy (NMS) to achieve the RBM objectives. The NMS embraces and conforms to Ministry Of Health sector strategic plan, Kenya interim poverty alleviation, Kenya vision 2030 and roll back malaria movement. The NMS aims to set up an enabling environment for the creation and implementation of such guidelines by coordinating stakeholders and efforts, strengthening partnerships, integrating systems, advocating resource priority, focusing national commitment and designing national guidelines on malaria for Kenya. The key targets for the strategy by 2006 were: 80% of Republic of Kenya (ROK) health facilities to have continuous and adequate supplies of drugs essential for the management of malaria 60% of fever cases which were treated at home by family members or caretakers to be managed appropriately 60% of the at-risk population to sleep under ITNs At least 50% of these nets to be regularly treated with insecticides.

35 2.11 Vector control 22 Vector control aims to decrease contacts between humans and vectors of human disease. Control of mosquitoes may prevent malaria as well as several other mosquito-borne diseases. Elimination of malaria in an area does not require the elimination of all Anopheles mosquitoes capable of transmitting the disease. Socio-economic improvements (e.g., houses with screened windows, air conditioning) combined with vector reduction efforts and effective treatments have led to the elimination of malaria without the complete elimination of the vectors Insecticide-Treated Bed Nets The use of ITNs treated with synthetic pyrethroids such as deltamethrin, permethrin alphacypermethrin or lambda-cyhalothrin is increasing fast in many malarial parts of the world including, sub-saharan African countries. The efficacy of ITNs in reducing morbidity and mortality due to malaria has been well documented in many publications (Lengeler, 2004). ITN's act in several ways: Firstly, intact nets provide a physical barrier, so reducing man-mosquito contact. Secondly the insecticide impregnated in the net knocks down and often kills mosquitoes that contact the net. The dosage required for knockdown is well below the threshold level of mammalian toxicity. This extra barrier makes insecticide-treated nets advantageous over untreated nets, such that a treated net can prevent biting even if it is torn. If the ITNs are used by a whole community, the insecticidal effect results in reduced longevity of female Anopheles mosquitoes so that few survive for the time required for development of the malaria parasite to the sporozoite stage in the mosquito. This reduces malaria transmission (Curtis et al, 1998). Thirdly, the pyrethroid insecticides, which are currently the only ones recommended to be used for impregnation of bed nets, have

36 23 deterrent and repellent properties so may prevent entry of mosquitoes into the room and thus offering another possible mechanism by which ITNs can partially protect sleepers against mosquitoes and malaria infection. The Roll Back Malaria (RBM) partners mutually agreed to set a goal to halve morbidity and mortality due to malaria by 2010 (WHO-RBM, 2003). For this, they advocated implementation of four key strategies, of which one was the use of ITNs. WHO recommend ITNs as the key strategy for malaria control in the most vulnerable groups, i.e. children and pregnant women especially primigravidae. Other strategies included proper management of malaria cases, intermittent preventive treatment (IPT) of malaria in pregnancy and early warning and containment of malaria epidemics (WHO, 2007). It is estimated that with a high coverage of ITNs in malaria endemic settings between 6 and 35 lives could be saved each year per 1000 children under five years who are provided for (Alaii et al, 2003). ITNs also reduce incidence of malaria episodes by about 48% and reduce incidence of severe malaria by up to 45% (WHO, 2007). Furthermore use of ITNs reduces the risk of maternal anemia and incidence of malaria illness by 45% among women in their first pregnancies and by 63% among those who have been pregnant more than once. It was also shown by Curtis et a1 (1998) that anemia associated with malaria in children of all ages was reduced. There was no evidence among these studies or trials that ITNs caused adverse effects in pregnant women or development of their infants. Several studies of communities supplied with ITNs show reduction in number of infective bites per year or Entomological Inoculation Rate (EIR) (Magesa et a1, 1991). This is attributed to the reduction of Anopheles population density and sporozoite rates in mosquitoes due to the killing effect of the insecticide. Untreated bed nets alone do not

37 24 provide much protection against malaria once they become torn. Untreated nets could even be harmful to those not under a net due to diversion of mosquitoes from the net to unprotected individuals within the same room (Lines et al, 1987). However there is evidence from studies conducted in Tanzania, Ghana and Kenya that people without nets that sleep near to people with insecticide treated nets are partially protected against mosquito biting and/or malaria (Lines et al, 1987). Untreated bed nets form a protective barrier around persons using them. However, mosquitoes can feed on people through the nets, and nets with even a few small holes provide little, if any, protection. The application of a residual insecticide greatly enhances the protective efficacy of bed nets. The insecticides used for treatment kill mosquitoes and other insects. The insecticides also have repellent properties that reduce the number of mosquitoes that enter the house and attempt to feed. In addition, if high community coverage is achieved, the numbers and longevity of mosquitoes will be reduced. When this happens, all members of the community are protected, regardless of bed net ownership. To achieve such effects, high community coverage is required, as for indoor residual spray. There are several types of nets available. Nets may vary by size, material, and/or treatment. Most nets are made of polyester but nets are also available in cotton, polyethylene, or polypropylene. Currently, only pyrethroid insecticides are approved for use on ITNs. These insecticides have very low mammalian toxicity but are highly toxic to insects and have a rapid knockdown effect, even at very low doses. Pyrethroids have a high residual effect: they do not rapidly break down unless washed or exposed to sunlight. Previously, nets had to be retreated at intervals of 6-12 months, more frequently if the nets were washed. Nets were

38 25 retreated by simply dipping them in a mixture of water and insecticide and allowing them to dry in a shady place. The need for frequent retreatment was a major barrier to full implementation of ITNs in endemic countries. The additional cost of the insecticide and the lack of understanding of its importance resulted in very low retreatment rates in most African countries (WHO, 2008). Plate 1 and Plate 2 show how the Long lasting Insecticide treated nets are used for drying small fish. The Long lasting insecticide treated nets are perceived by fishermen to be strong and thus the fish dry in a straight form. Plate 1: Fishermen along the beach of Lake Victoria using LLINs for fishing and drying OMENA (Daily Nation 5th December 2008).

39 26 Plate 2: LLINs being prepared for overnight fishing (Malawi Magazine, 4th June 2008) Mosquito behavioral effects towards pyrethroids Pyrethroids were developed from prolonged efforts to improve biological and chemical stability of the natural pyrethrins, which have long been known for their insecticidal effects. Due to the instability of pyrethrins, synthetic pyrethroids were developed. As well as causing a knockdown effect, insects encountering pyrethroids show restless behavior and hyper excitability caused by involvement of the central nervous system. Pyrethroids may also have an anti-feeding effect on Anopheles mosquitoes (Magoma et la, 2006). A large number of pyrethroid compounds have been synthesized during recent years (Miller et al, 1995). Many synthetic pyrethroids, such as permethrin, are known to have an excito-repellent property that affects the behavior of mosquitoes reducing the rate of entry into house and increasing the rate of early exit from houses (Magesa et al, 1991 ;

40 27 Curtis at el, 1998). These induced behavioral changes may make mosquitoes shift from an endophilic and endophagic pattern to exophilic and exophagic behavior. Reduced house entry and/or early exit may help to limit human-vector contact. However, mosquitoes may also respond to the use of ITNs in ways that compromise their efficacy, for example they may shift their biting times (Graham et al, 2005). Such changes in mosquito behavior may result in mosquitoes biting before people retire to bed so reducing the efficacy of ITNs Resistance effects of pyrethroids Insecticide resistance mechanisms should be distinguished from insecticide avoidance behavior discussed above. The two major forms of biochemical resistance are target-site resistance, which occurs when the insecticide no longer binds to its target, and detoxification enzyme-based resistance, which occurs when enhanced levels or modified activities of esterases, oxidases, or glutathione S-transferases (GST) prevent the insecticide from reaching its site of action (Brogdon and McAllister, 1998). The emergence of resistance in most species of Anopheles mosquitoes, including Anopheles gambiae s.s and Anopheles funestus, regarded as the most important malaria vectors in Africa (Magoma et al, 2006), is of great concern to malaria control, especially as development of resistance to pyrethroids may compromise the effectiveness of insecticide treated nets. There is evidence for resistance mechanisms arising from mutation of the sodium channel receptor, the so called Kdr mutation that has been reported in Anopheles gambiae s.s from West Africa as well as in East Africa (Chandre et al, 2007). In addition to this target-site resistance, Vulule et al (1996) observed increased permethrin tolerance (PT) due to elevated levels of oxidases and esterases among

41 28 Anopheles gambiae following the introduction of permethrin-impregnated bed nets in some villages near Kisumu in western Kenya Immunity status and rebound of morbidity and mortality In high transmission areas people develop acquired immunity against malaria from receiving infective bites frequently. It has been suggested (Lengeler, 2004), that after long term reduction in malaria transmission without eradication, due to the high coverage of ITNs or other forms of vector control, acquisition of natural immunity against malaria may be delayed in children. Without this normal development of immunity a shift in the age of acquired immunity and a rebound in morbidity and mortality at older ages may result. Maxwell et al (1999) compared a series of health indices in young and older children in villages with and without ITNs. The level of anemia and malaria fever in young children was still reduced after 3-4 years use of ITNs. In older children, though reduction in fever and anemia was not significant, there was no sign of increases in morbidity in this age group as would be expected by the rebound hypothesis. In a study conducted in Kenya reported highly significant reduction in infant mortality. Follow-up after several years showed continued reductions in infant mortality and neither an increase nor decrease in mortality of older children (Lindblade, 2005). Curtis (2009 in press) pointed out that the benefits to children s health due to ITNs have been considerably greater than those so far observed with anti-malaria vaccines. A useful role of vaccines may be to replace any lost immunity due to reduced exposure to malaria which may result from long-term use of ITNs.

42 Evolution of Long-Lasting Insecticide-treated Nets (LLINs) Mosquito netting use dates from the mid 1700s, use of mosquito nets has been dated to prehistoric times. It is said that Cleopatra, Queen of Egypt, also slept under a mosquito net. Mosquito nets were used during the malaria-plagued construction of the Suez Canal. (Wikipedia, retrieved on 11/09/2010) Mosquito nets treated with insecticides known as insecticide treated nets (ITNs) -- were developed in the 1980s for malaria prevention. Insecticide-treated nets (ITN) are estimated to be twice as effective as untreated nets, and offer greater than 70% protection compared with no net. These nets are dip treated using a synthetic pyrethroid insecticide such as deltamethrin or permethrin which will double the protection over a non-treated net by killing and repelling mosquitoes. For maximum effectiveness, the nets should be re-impregnated with insecticide every six months. New technologies like Permanet, Olyset or DawaPlus allow for production of long-lasting insecticidal mosquito nets (LLINs), which release insecticide for approximately 5 years (Wikipedia, 2010). Standard ITNs must be replaced or re-treated with insecticide after six washes and, therefore, are not seen as a convenient, effective long-term solution to the malaria problem. As a result, the mosquito netting and pesticide industries developed so-called long-lasting insecticidal mosquito nets (LLINs), which also use pyrethroid insecticides. There are two types of LLINs, one which is polyester netting and the insecticide is bound to the external surface of the netting fiber using a resin and another which incorporates the insecticide into a polyethylene fiber which then releases the insecticide slowly over 5 years.

43 30 More recently, several companies have developed long-lasting insecticide-treated nets (LLINs) that retain lethal concentrations of insecticide for at least 3 years. The WHO Pesticide Evaluation Scheme has recommended five of these LLINs for use in the prevention of malaria. CDC is currently testing these and other LLINs in Atlanta and Kenya. The WHO Pesticide Evaluation Scheme recommends the following LLINs: DuraNet (Clarke Mosquito Control), Interceptor Net (BASF), NetProtect (Intelligent Insect Control) (also marketed as ICON Life by Syngenta), Olyset Net (Sumitomo Chemical) and PermaNet 2.0 (Vestergaard-Frandsen). It should now be possible to avoid the need to retreat nets by the use of long lasting insecticidal nets (LLINs). These nets are treated in the factory with insecticide either incorporated into, or coated around the fibres, so resisting multiple washes. Application of LLINs is currently growing in many malaria endemic areas and these nets are claimed to retain their insecticidal properties for their physical life in domestic use despite many washes (Tami.et a1, 2004; Lindblade et al, 2005). Physical life has been given as 3-4 and 4-5 years for polyesters and polyethylene nets respectively (Rollback Malaria and WHO, 2003). Currently several insecticide and net manufacturers are active in developing long lasting nets technology. Other beneficial effects of using LLINs over conventionally treated bed nets include avoiding problems associated with storage and handling of insecticides by non professionals and reducing risks of environmental contamination caused by insecticides released into water bodies, foods etc ( Najera, 2001) Olyset Currently Olyset nets are locally produced in East Africa by the A-Z, Textile Industry in Arusha, Tanzania. Olyset nets have permethrin incorporated into the polyethylene material during the manufacturing process at a 2% concentrations corresponding to 1000

44 31 mg/m 2. Olyset nets are very strong due to their thick fibres of high density polyethylene which gives a strength about 180 denier despite the wide mesh of 4mm. Their durability and long-lasting insecticidal properties may be suitable where regular re-treatment with insecticides has not been organized as is the case in most rural settings in malaria endemic areas in Sub-Saharan Africa (Tami et a1, 2004). However the current costs of LLINs may still be prohibitive in poor areas. Olyset net is a polyethylene net with 2 % permethrin incorporated within fiber. Over time, insecticide migrates to the surface of the yarn, replacing the one that has been removed by washing. This migration is a temperature dependent process and exposure of nets to heat after washing (e.g. few hours to sun) can accelerate it PermaNet 2.0 A ready-to-use mosquito bed net, PermaNet 2.0 is impregnated with an odorless and biodegradable insecticide called deltamethrin that is mixed in a resin, coating the netting fibers. A progressive release of insecticide from the resin guarantees retention of the net's efficacy even after 20 washes. PermaNet 2.0 bed net is environment-friendly as it reduces the total exposure of insecticide in the environment. This bed net requires no retreatment or dipping and a dirt repellent feature has been added to keep it clean longer. PermaNet 2.0 has a WHOPES (World Health Organization Pesticide Evaluation Scheme) recommendation, which declares it safe and effective for the prevention and control of malaria and other vector-borne diseases PermaNet 2.0 bed net is made of 100% polyester in either 75 or 100 deniers, and is available in various colors, shapes and sizes.

45 2.13 Indoor Residual Spraying 32 Many malaria vectors are endophilic, resting inside houses after taking a blood meal. These mosquitoes are particularly susceptible to control through indoor residual spraying (IRS). As its name implies, IRS involves coating the walls and other surfaces of a house with a residual insecticide (Plate 3). For several months, the insecticide will kill mosquitoes and other insects that come in contact with these surfaces. IRS does not directly prevent people from being bitten by mosquitoes. Rather, it usually kills mosquitoes after they have fed, if they come to rest on the sprayed surface. IRS thus prevents transmission of infection to other persons. To be effective, IRS must be applied to a very high proportion of households in an area (usually >70%). Plate 3: Demonstration of Indoor Residual Spraying. IRS with DDT and dieldrin was the primary malaria control method used during the Global Malaria Eradication Campaign ( ). The campaign did not achieve its stated objective but it did eliminate malaria from several areas and sharply reduced the burden of malaria disease in others. Kenya was one of the countries where pilot IRS

46 33 projects were initiated in the 1950s and 1960s as part of the global malaria eradication campaign. The Pare Taveta IRS project in Kenya and Tanzania was implemented between 1955 and 1959 using dieldrin. The project resulted in a complete disappearance of An. funestus, a strongly anthropophilic and endophilic species while the An. gambiae complex An. gambiae was reduced by 80%. The impact on the An. gambiae complex was less dramatic than that on An. funestus which may have been the result of the presence of An. arabiensis which is less endophilic and anthropophilic in its behavior than An. funestus. The sporozoite rate was reduced to < 1% and the Plasmodium index amongst children was reduced from 35% to below 5% (Bradley, 1991; Najera, 2001). However, when the spraying ceased, both vector abundance and malaria transmission rate increased. Later on, another pilot project was conducted in in the Kisumu area bordering Lake Victoria using fenitrothion (40% WP). There was a 96% reduction in infection incidence, 43.5% reduction in overall mortality, 65.6% reduction in disease prevalence, 40.8% reduction in infant mortality and 96% reduction in infection inoculation rate were achieved (Payne et al, 1976). Cessation of the spraying was followed by a rebound of the malaria transmission and burden to the pre-project levels Larval Control Source reduction is the method of choice for mosquito control when the mosquito species targeted are concentrated in a small number of discrete habitats. The larval habitats may be destroyed by filling depressions that collect water, by draining swamps, or by ditching marshy areas to remove standing water (Plate 4). Container-breeding mosquitoes are particularly susceptible to source reduction as people can be educated to remove or cover standing water in cans, cups, and rain barrels around houses. Mosquitoes that breed in irrigation water can be controlled through careful water management.

47 2.15 Fogging or area spraying 34 Fogging is primarily reserved for emergency situations: halting epidemics or rapidly reducing adult mosquito populations when they have become severe pests (Plate 5). Plate 4: A pond which is a potential breeding site for mosquito larvae. Fogging and area sprays must be properly timed to coincide with the time of peak adult activity, because resting mosquitoes are often found in areas that are difficult for the insecticide to reach (e.g., under leaves, in small crevices).

48 35 Plate 5: A fogging machine spraying insecticide for malaria control Personal protection measures Include the use of window screens, ITNs and repellents (such as DEET) and wearing light-colored clothes, long pants and long-sleeved shirts. Well-constructed houses with window screens are effective for preventing biting by mosquitoes that bite indoors and likely contributed much to the elimination of malaria from the United States and Europe. Sterile male release has been successfully applied in several small-scale areas. However, the need for large numbers of mosquitoes for release makes this approach impractical for most areas. Genetic modification of malaria vectors aims to develop mosquitoes that are refractory to the parasite. This approach is still several years from application in field settings Economic costs of malaria Malaria has a significant measurable direct and in-direct cost, and is a major constraint to economic development. The direct costs include a combination of personal and public expenditures on preventive and treatment of the diseases. Personal expenditure include

49 36 individuals or family spending on ITNs, LLIN, doctors fees, anti-malarial drugs, transport to the health facilities and support for the patient. Public expenditure includes spending by governments on maintaining health facilities and health care infrastructure, publicly managed vector control, education and research. The indirect costs of malaria include lost productivity or income associated with illness of death like lost work days or absenteeism from formal employment. Since the inception of roll back malaria in 1998, and particularly since the Abuja summit 2000, malaria prevention and control have become domestic and international priorities. International spending for malaria has increased at least two fold since 1998 from USD 60M to USD 120 M (WHO/UNICEF 2003). Malaria control is financed through mainly three methods: Private primarily households. Government expenditures Donor support. The average recurred cost for inpatient treatment for severe malaria is USD 35 per admission in a typical Kenyan district hospital. The Global Fund for AIDS, Tuberculosis and Malaria has significantly increased the financial resources for malaria control in Africa. In Abuja declaration the Africa heads of state called for the allocation of new resourcesat least USD 1billion per year from African countries and their development partners.

50 37 CHAPTER THREE MATERIALS AND METHODS 3.1 Research Design This was a cross-sectional study with mosquito nets and the use of the nets by the community as the unit of observation. Two types of LLIN nets, PermaNet 2.0 and Olyset were randomly sampled from Kadibo division where they had been distributed to households by the Ministry of health between 2006 and 2007 under the routine MCH programme and under the 2006 integrated measles campaign (MOH Annual report, 2006). After sampling of the LLINs, a series of bioassays were conducted at the CDC/KEMRI laboratories in Kisian to determine the net mosquito knock down. 3.2 Study area The study was carried out between December 2008 and January 2009 in Kadibo division, Kisumu district as shown in Figure 7. The area is located on the shores of Lake Victoria and has intense perennial malaria transmission. According the report from the Divisional Health Center at Rabuor, Malaria is endemic in this division with Plasmodium falciparum prevalence rates in asymptomatic children age 2 9 years between 45 % and 68%. Main vectors are Anopheles gambiae and An. funestus with Entomological Inoculation Rates (EIR) estimated around 7 infective bites per person per year. Malaria transmission occurs throughout the year, with peaks during May through July, and October through November. More than 95% of these infections are due to Plasmodium falciparum, and almost all of the remainder is P. malariae (Brieger et al, 1996). Infections with P. ovale are rare. Study site was in all the five locations of the division namely Kochieng, Kawino, Nyamware, Bwanda and Katho locations.

51 38 Figure 7: Map of the study area. 3.3 Target population The study targeted households that benefited from the distribution of Olyset nets under the ministry of health MCH programme and the integrated measles campaign of the distribution of PermaNet 2.0 in 2006 within Kadibo division (Table 1). Table 1: Population in Kadibo Division. Location within Kadibo division Total Population Number of households Number of PermaNet 2.0 Distributed in 2006 Bwanda Kawino Kochieng Kombura TOTAL Number of Olyset Distributed in 2006

52 Sample size estimate The sample size was determined using the formula: n = Z²p (1-p) (Fisher et al, 1998) Where e² n = required sample size z = confidence level at 95% (standard value of 1.96) p = estimated prevalence of estimated usage of LLINs in the project area which was 85% (MOH report, 2006) e = margin of error at 4% (standard value of 0.04) Table 2: Number of sampled households from each location in Kadibo Division. Location within Total Total Number of households sampled Kadibo division population households (95% Level of Confidence) Bwanda Kawino Kochieng Kombura TOTAL Therefore: n = 1.96*1.96 * 0.85* *0.04 n = 306 Therefore 306 households were sampled as illustrated in Table 2 above.

53 3.5 Data collection Sampling of the bednets Both purposive and random sampling methods were used during this research. According to the protocol by WHO Pesticide Evaluation Scheme (2005), four bed nets are enough to test for mosquito knockdown. However 1 bednet was collected from 10 households randomly selected making a total of 10 bed nets. It was agreed that if a bed net was not found in the house selected, a bed net should be taken from the neighboring The Olyset and PermaNet 2.0 nets which were formerly distributed in the villages of Kadibo, Kisumu district in may 2006 by the Ministry of Public Health and Sanitation, were sampled in January Village households were asked whether they had a net. If the answer was yes they respondent was requested for the date of acquisition. The room where the net was hanged was identified and the label of Olyset or PermaNet 2.0 which is inside the net was identified. 5 PermaNet 2.0 and 5 Olyset were sampled from 10 different households. These were then exchanged with new LLINs for the collected ones. The nets were stored in plastic bags at room temperature. The bed net chosen for evaluation was always the one under which the study child had slept the previous night Data collection tools Training of research assistants on the questionnaire preceded its pre-testing in a pilot study of households in Kolwa location within Kisumu district located 10 kilometers from the study site, Kadibo division. The research tools were adjusted accordingly after analysis of the preliminary data. Data was collected by trained personnel using a pre-coded and pre-tested questionnaire (Annex 2). The questionnaire contained questions related to the effectiveness of the bed nets in preventing malaria attack in children under 5 years, the utilization and perceptions

54 41 related to the nets, as well as certain practices related to the nets, mainly retreating and washing. The questionnaire included questions which were related to malaria prophylaxis or indicators of socioeconomic status. Respondents were interviewed by trained interviewers, using default wording. The questionnaire consisted mainly of closed questions. Respondents were not prompted, only spontaneously given answers were marked on the questionnaire sheet by the interviewer. Data entry was limited to two persons. The interviews took place at the home of the respondent during a day which the interviewer had booked before. To measure the proportion of children not sleeping under a bed net, it was asked whether the child had slept under a bed net the night before the interview. This was the main outcome measure of the study. Condition and installation of bed nets were evaluated during a home visit in order to compare not only the percentages of bed nets used, but also the percentages of effectively used bed nets Focus Group Discussions (FGD) Focused Group Discussions were conducted in four villages to complement and further explain the information obtained through the questionnaire (Annex 5). The clusters were selected giving consideration to the size of the area and the population, preference being given to areas of higher population density. In each village, two separate groups comprising of males only and females only. The groups ranged generally from about eight people to about twelve. Key issues and questions raised by results from the questionnaires were put forth for discussion. The questions focused on the distribution of the nets (the mechanism, price, number per household, and instructions to the recipients), the practices and utilization of the nets (including selling the nets, focus on children under five years of age), as well as pros and cons of the nets (Annex 5). The participants

55 42 were encouraged to discuss freely while refraining from giving leading phrases to guide their response Key Informant Interview guides This was used to get deeper information on malaria prevention at the health facilities. The cost of the various forms of malaria treatments were also captured during these interviews. The in-depth interviews were conducted at the three health facilities in the Division namely, Rabuor, Nyangande and Hongo Gosa Health dispensaries Inclusion Criteria All household with PermaNet 2.0 and Olyset had children under 5 years were selected randomly for the study. The household should have acquired the nets in the year 2006 measles integrated campaign period. The respondents were the household head, mother or the caretaker of the children under 5 year Exclusion criteria All those household that did not have any type of LLINs and those who did not give their consent for the research were not included in the study. Also households that did not have under 5 year children were excluded Logistical and ethical consideration The permission to conduct the study was granted by Kenyatta University and Institutional clearance from the Ministry Public Health and Sanitation before commencing the study. In the field, informed consent was received from all respondents. Every household from which a bed net was taken was given a new LLIN in exchange. 3.6 Laboratory Bioassay Tests were done using standard WHO cones with a three minutes exposure time. In order to have an accurate exposure, batches of only 10 female mosquitoes (An. gambiae,

56 43 Kisumu susceptible strain) were introduced in cones at a time. Four repeats were done for each net sample (40 mosquitoes). After testing, mosquitoes were grouped in plastic cups covered with netting with sucrose solution provided and maintained for 24 h at 30 C and 80% humidity. Percentage mortality was noted after 24 hours according to two criteria: "effective" mortality (i.e. mosquito looks dead and does not move any more, the endpoint in the standard WHO methodology) and "functional" mortality (mosquito still moves but in such a feeble and uncoordinated way that it would not survive in a natural environment). Knock-down (KD) rates were noted 3minutes, 60 minutes and 24 Hrs after exposure Procedure for rearing mosquito Adult Anopheles gambie (Kisumu strain) were maintained in net cages with white sheets on the floor. Two small tubes containing 10% glucose solution and bowls emerging pupae covered with a cone, with a small aperture at the tip were placed in each cage. Glucose solution is essential to maintain the male mosquitoes population in the cage and also provide energy to the female mosquitoes when they are not feeding on blood. The pupal bowl was covered with a cone so that gravid female mosquitoes are restricted from laying eggs in it and emerging adults are free to emerge and fly into the cage. A small bowl of water with a piece of sponge soaked in it was placed on top of the cage and clear plastic covers were placed over cages to provide relative humidity of 60-70%. Water was topped up weekly. Adult female mosquitoes were blood-fed twice a week on an artificial membrane system using defibrinated horse blood. Feeders were filled with blood and covered with parafilm membrane and heated in electrical Hemotek feeders, to make them attractive to mosquitoes. Feeders were placed on top of the cages and mosquitoes were encouraged to feed by gently breathing on the feeder.

57 44 An egg bowl lined with filter paper half-filled with tap water was placed in the cages. On the third morning after blood feeding, the egg bowl was removed from the cage and left for the eggs to hatch. Once hatched the larvae were transferred into larval bowls with about 2 cm depth of water and a small amount of grass and soil. Anopheles larvae feed at the surface and a small amount of baby food (dry muesli) was sprinkled on the water surface. The larvae developed into pupae in about 7 days and these were transferred into pupa bowls using a pipette or strained using a fine mesh sieve. The emerging adults were transferred to the cages using an aspirator and allowed to develop for three days before bioassay tests were performed Introducing the mosquitoes for bioassay Contact bioassays were carried out according to WHOPES guidelines using the WHO standard plastic cone. Susceptible laboratory reared An. gambiae (Kisumu strain) were exposed in batches of five to treated or untreated netting in WHO cones for three minutes, after which they were held for 60 min then 24 hours for mortality scoring. Test mosquitoes were c. 100 non-blood fed, 4 5 days old, glucose 10% -reared An. gambiae (Kisumu strain).

58 45 Plate 6: Sampled nets from the households. Plate 7: Insertion of the WHO cones for the bioassays

59 46 Plate 8: Mosquitoes inside the control net. Plate 9: Aspirator used in introducing the mosquitoes in the cones.

60 47 Plate 10: 4-5 day old mosquitoes used in the experiment. Using WHO plastic cones, a batch of ten 4 day old starved female Anopheles (Kisumu strain) mosquitoes, were inserted into the cone and a circular piece of cardboard was placed on the other side of the net and clipped to it to prevent mosquitoes escaping through the 4 mm mesh of the Olyset, PermaNet 2.0, Supanet and control net. Mosquitoes were exposed for 3 minutes according to the WHO standard exposure bioassays, and then were transferred by an aspirator to cardboard cups topped with untreated netting. Mosquitoes were provided with 10% sugar solution (WHO, 2003) and kept in a cupboard chamber. The tests were repeated twice and an average for each net taken and recorded. The tests were conducted under room temperature of 27ºC ± 2ºC and 80% relative humidity.

61 Data management and analysis Data entry, data cleaning, and analysis was done using SPSS Version 10. For the analysis of net performance (mosquito knockdown bioassay) the mean of all sampled nets was calculated. The assessment of between-net variability of insecticide concentration the standard deviation of mosquito knockdown was expressed as percent of the sample mean (coefficient of variation). Intra-net variability was expressed as the difference of samples of the same net to the mean expressed as percent of the mean and then averaged over the sample. The analysis of statistical differences of inter-intra net variations of Permanet and Olyset outcomes was done using ANOVA. Univariate analysis was carried out considering all co-variables of interest and tested using Chi-squared test for categorical and t-test for continuous variables depending on the validity of the assumption of normal distribution of values. Multivariate analysis (linear or logistic regression models as appropriate) was used to verify any associations found in the univariate analysis.

62 49 CHAPTER FOUR RESULTS AND DISCUSSION Extensive research has been done over the past 10 years on technical and managerial aspects of insecticide treated net interventions (ITNs) as well as their efficacy and, to a lower extent, their effectiveness (Miller et al. 1995; Lengeler 2004). Emphasis is now on long-lasting insecticidal nets (LLINs) that are factory pre-treated and retain their biological efficacy for at least 20 standard washes under laboratory conditions and 3 years of use under field conditions (WHO 2005a). This study sampled 306 respondents from Kadibo Division in Kisumu District and their responses analyzed to establish the socio-cultural practices which affect the insecticidal activity of long lasting insecticide treated nets used as a method for malaria prevention within children under five years. The household questionnaire, key informant interview and observation were the main data collection tools used in the survey. The insecticidal activity of the long lasting insecticide treated nets was tested through a laboratory bioassay using WHO cone. Starved female Anopheles mosquito 3-4 days old were used for the bioassay from which the number of mosquitoes killed after 3 minutes, 60 minutes and 24 hours were recorded for all the sample nets Household characteristics The mean age for the respondents was years with a standard deviation of with a range of years. As illustrated in Figure 8, most of the respondents were between the ages of years with the oldest being 79 years old. From these there were more female than male respondents with 61% of the respondents being female while 39% being male. Most of the respondents were mothers followed closely with fathers and grandmothers (33% were fathers, while 66% were mothers, 1% were grandmothers).

63 Percent 50 At least 67% of the respondents completed primary level education, while 27% completed secondary level, and 3% completed tertiary while 2% completed university education age of respondent Figure 8: Age of the respondents. 4.2 Objective 1: Proportion of families with children under 5 years using PermaNet 2.0 to Olyset in Kadibo division The use of the long lasting insecticide treated nets is one of the strategies used by the Ministry of Public Health and Sanitation and the Ministry of Medical services to control the incidences of malaria among children under five years. However the success of the mosquito net depends on how best the mosquito nets are put into use by the family members at the household level. A number of factors as elaborated below explain the access of the mosquito net in Kadibo division and whether they are being used by the target children under 5 years.

64 Percent Number of sleeping areas in the house The sleeping area available for the children under 5 years ranged between 1 to 5 within the sampled households as presented in Figure 9 below. A significant number of the households had only two sleeping areas (45%), while households having one and three sleeping areas were 25% with households having 4 sleeping areas being 3% and households having 5 sleeping areas being 2% number of sleeping room in house Figure 9: The number of sleeping areas in the respondents' house. Table 3 Distribution of the sleeping areas for children under 5 years Sleeping area for Children PermaNet 2.0 Olyset % Same room with the parents % Different room with the parents % Kitchen 6 3 3% Total %

65 52 As shown in Table 3, a total of 51% of households using PermaNet 2.0 were sleeping in the same room as the parents, 34% were sleeping in a one bed roomed house and 12% were sleeping in the sitting room while 2% were sleeping in the kitchen, 47% of households using Olyset were sleeping in a one roomed house, 38% were sleeping in one bed roomed house, 15% in the sitting room and 3% in the kitchen. The one roomed huts are multipurpose huts used as kitchen, sitting room and bedroom. For the two roomed hut, a partition which is not attached to the roof, divides the hut, thus allowing smoke from the cooking area into the next room. According to Figure 9, the proportion of sleeping areas exposed to heat and smoke from cooking area is 70 %. The main source of fuel for cooking and lighting is firewood and charcoal thereby emitting smoke which is obviously adsorbed into the matrix of the LLINs placed over the beds. The heat generated by the fire is known to accelerate the release of the insecticide from the net while the adsorbed particles of smoke mask the insecticide remaining in the net thus reducing the effectiveness of the LLINs. Though some children were using kitchen as their sleeping area, there was concern on the way the nets were being hanged Number of long lasting insecticide treated nets in the house. Table 4 Number of long lasting insecticide treated nets in the respondent house. Number of long lasting insecticide treated nets in the house PermaNet 2.0 Olyset 95% CL p-value % % % % % % % Total %

66 53 From the respondents who were interviewed 47% had one net, 29% had two nets, 14% had three nets and 5% had four. In all houses visited there was a mixture of LLINs and ITNs and the number given above are specific to LLINs. The high number of households with one net (Table 4), does not correspond to the need of the nets as indicated by the high number of the sleeping rooms in Table 3 which shows that majority of households have two sleeping sites. Thus this indicates that there are some under 5 years old children who may be sleeping in other rooms and lack the mosquito net. This is because the current government policy on LLINs is the distribution of nets to children under five at subsidized prices during the routine clinic at the MCHs Child under 5 years sleeping under the long lasting insecticide treated nets the previous night The use of the mosquito net was well responded to with 93% of the respondent confirming that the nets were used last night, out of which 87% of the ones using PermaNet 2.0 slept under the net and 82% of those using Olyset slept under the net ( Figure 10). Figure 10: A figure showing whether a child slept under a long lasting insecticide treated nets.

67 54 However, 7% did not sleep under the net. A closer look at this group of children compared closely with the children sleeping in the kitchen and in a one roomed house. The fact being that only one net was available for the family of which the father and mother who were using the bed are the ones using the net. Table 5: The usage of the long lasting insecticide treated nets last night. Person who slept under the long lasting insecticide treated nets last night PermaNet 2.0 Olyset 95%CL p-value % Child under 5 years % Mother % Father % Total % Table 5 presents the people who use the available net within the household out which, 57% are children under 5, followed by their parents at 43%. This shows that there is some level of awareness at the community level on the use of the nets as a barrier for mosquito bit thus preventing malaria incidences. However a total of 116 children out of 171 slept under the PermaNet 2.0 net, 55% slept under Olyset. Therefore PermaNet 2.0 is the most preferred brand of net being used by the children under 5 years Sleeping time for the child under 5 years As illustrated in Figure 11, 35% of the children sleep at 7p.m, 45% sleep at 8p.m, 19% sleep at 9p.m and 1% sleeps at 10p.m. Being that mosquitoes start biting from 6-8p.m then a total of 100% of children are vulnerable to mosquito attacks. The under-fives children pose a challenge compared to the pregnant women alike. The elusive question is

68 Time 55 whether mosquito nets provided to the under-fives will reach them and if they reach them whether they are effective in preventing against mosquito bite and thus contracting malaria otherwise. The over-riding assumption is that if children who sleep under mosquito nets are more likely to share a bed with their mothers in households with at least one mosquito net, then the primary person being protected is not the child; the child benefits because it happens to share a bed with the parent. Time when children under 5 yrs go to sleep 11p.m 10p.m 9p.m 8p.m Olyset PermaNet 2.0 7p.m Number of Children Figure 11: The time when children under 5 years slept. Percentages for sleeping under bed nets in general and specifically for children under five years of age and for pregnant women are all high compared to other studies which have been done in Sudan (Hassan et al, 2008). This determines the effectiveness of the bed nets as they are not being utilized regularly and are not being reserved and utilized by guest in the houses. Despite the good result in the utilization of the net, there is still a considerable number of children who have had malaria attack more than three times and this differ significantly within the two nets. This may be due to the fact that the children go to bed very early at 7 8p.m and some family heads (i.e. mother and father) mount the bed nets only late at night before they go to sleep, providing the mosquitoes with

69 56 ample time to bite the children ( Ritmeijer et al, 2007). The analyses point in general to a significant relationship between the education level of the informant and the practices related to LLINS. Those who have not received formal education actually received more bed nets. One possible reason for this might be that those who pursued their education were not as available as others who did not during the time of distribution of the nets. The facts that those who did not receive formal education were more likely to have lost their nets and that those who sold their nets belonged to this group raise other possible explanations. If bed nets are viewed just as a commodity to be obtained and then sold for financial gain, this could be a reason for asking for or buying more bed nets and then selling them. It was also observed that some houses did not use the bed nets for purposes other than the one intended for them instead they were kept in the handbags for visitors. The reason for this came out during the focused group discussion that nets are not good for young children. All these facts suggest that those who received the nets did not fully appreciate the benefits and importance of the bed nets. The effect of education is reflected clearly in the figures related to the utilization of the nets, with those receiving education sleeping more under the bed nets and letting more under 5 years and pregnant women sleep under the bed nets. Owing to their role in the family, women have been reported to be more inclined than men to buy health-maintaining items such as bed nets. Women are responsible for the health of their family members, take care of children and as a result usually more aware of children vulnerability to malaria. Most women were informed about malaria in children and were aware that LLINs were the preferred method of controlling malaria in children under five, however due to the economical constraint these women depended mostly of donation or on subsidized nets from the health facilities. Of which if the women is not expecting any other child she cannot have access

70 57 of the nets at the health facilities. Community misconception regarding the transmission of malaria points at the education level of the respondents, though most of them completed primary level education but still some did not know what really causes malaria however most of them knew of the various methods of preventing malaria. The high number of households with one net does not correspond to the need of the nets as indicated by the high number of the sleeping rooms in Figure 18 which shows that majority of households have two sleeping sites. Thus this indicates that there are some under 5 years old children who may be sleeping in other rooms and lack the mosquito net. This is because the current government policy on LLINs is the distribution of nets to children under five at subsidized prices during the routine clinic at the MCHs. 4.3 Objective 2: Cultural perception which hinders or promotes the use of PermaNet 2.0 and Olyset nets within households having children less than 5 years in Kadibo division Research have demonstrated that ITNs are an effective malaria control strategy, there have been many challenges to ITN distribution, acceptance and utilization when trying to implement large-scale ITN programs (D'Alessandro et al, 1995). Knowledge about the cause of malaria and about the existence of ITNs was low in many malaria-endemic communities (Aikins et al, 1994). For those areas which have been reached by publicity campaigns, high cost and lack of access were some of the reasons stated as to why ITNs were not used (Kachur et al, 2000) Number of times the long lasting insecticide treated nets had been washed Insecticide-treated bed nets and curtains (ITNs) have repeatedly been shown to reduce malaria morbidity and mortality in sub-saharan Africa (Lengeler, 2004). However, nets require yearly or twice-yearly treatment with insecticide to maintain their efficacy and, in most African countries, <10% of nets are adequately treated with insecticide (WHO

71 ). Long-lasting insecticidal nets (LLINs) are currently being promoted as the solution to low insecticide treatment rates in sub-saharan Africa (Guillet et al. 2001). Many believe that washing is the main factor causing loss of insecticide from nets. Therefore, wash resistance in the laboratory has been measured to represent long-lasting efficacy in field conditions (WHOPES 2001, 2004; Muller et al. 2002; Ordonez et al. 2002). In this study, the respondent had washed their nets for between once to fifteen times as shown in Figure 12 and Figure 13. The respondents who had washed their nets three times were 22%, twice were 16%, four times were 15%, once were 13%, five times were 9% with the rest varying between six to fifteen times. Figure 12: The number of times long lasting insecticide treated nets has been washed. The number of washing of the net is very important in the study because the efficacy of the net depends on how often the net is being washed. The net which had more washes is less effective. This study considered nets that had been used for 2 years, whose expected number of washings should not exceed 10. From figure 12 it is evident that majority of respondents adhered to this requirement with 75% of the respondents washing less than 5 times. For this study the number of

72 59 washing is not expected to be a factor contributing to the ineffectiveness of the LLINs. Ideally the insecticide is retained even after 20 washes by the LLINs (WHOPES, 2005). Figure 13: The last time long lasting insecticide treated nets was washed without insecticide. In response to the difficulty of promoting net retreatment, technical solutions that reduce or eliminate the need for retreatment of bednets have been sought. Manufacturers of PermaNet and Olyset have developed processes to incorporate insecticide into polyethylene fibers, which are then used to make netting material, or to bind insecticide onto polyester fibers during the manufacturing process using a resin. Figure 14 shows that 46% of respondent had washed the LLINs with insecticide for the past one month, 40% had washed in the last two months 14% had washed in the last three months. Figure 14: The last time the long lasting insecticide treated nets was soaked in insecticide. The effect of washing in his study compares with a study by Magoma et al (2006) who reported that diffusion of insecticides from inside the fiber of the net to the surface is temperature dependant. The manufactures of Olyset nets stated that the insecticide most diffused from inside the fiber to the surface.

73 60 After each wash some of the insecticide is thought to be removed from the surface, but active ingredient will diffuse from inside after a certain period of time following washing and heating. The result observed in the present study might be partly due to the time elapsed between the washing and testing which was five days. Heating was in the sun in a black plastic bag at 27.5" C-29.5' C for one day and this was probably not enough to generate insecticide to diffuse. Some studies suggest that because diffusion of insecticides is affected by temperature, if time between washing and the bioassays is too short there would not be enough time for insecticide to diffuse from inside the fiber to the surface. WHO (2001) state that it is important to leave enough time between washing and testing. However the reduction of the insecticidal activity in this study vary from a study conducted by Curtis et a1 (1998) who reported to the WHOPES on an unwashed Olyset net and Olyset nets which had been washed or washed plus heated to 80" C for 30 minutes. They observed that nets treated in all three ways were effective in killing and reducing feeding of free flying wild Anopheles mosquitoes they reported no evidence that the insecticidal power was reduced by five washes of nets in cold soapy water or that regenerating at 80" C was really required to replace insecticide removed during washes Number of holes in the long lasting insecticide treated nets The strenght of the nets was tested with the number of holes on the sampled households nets and out of which 12% of the households had nets with no holes however the period of acquisition was in Upto 63% of the households reported have nets with between 1-5 holes. 25% reported have nets with 6-45 holes on the nets as illustrated by Table 6 below.

74 61 Table 6: Presentation of then number of the holes on the long lasting insecticide treated nets. Number of holes in the net. PermaNet 2.0 Olyset %( Percentage) % % % % % % % % % % % More than % Prefered shape of the long lasting insecticide treated nets Table 7 below presents the preferred shape of the net which was dependant on the model of the house. From the respondent, 57% preferred oval compared with 43% preferred rectangular. This was because the oval shaped net only requires one point for hanging while the rectangular shape required four point and thus for a small multipurpose room it was very difficult for the bed net users to hang the rectangular nets. Table 7: Representation of the preferred shape of the long lasting insecticide treated nets. Preferred shape of PermaNet 2.0 Olyset % ( Percentage) the net Oval % Rectangular % Total %

75 62 Some respondents reported that the new nets had killed at least child and this happened during the 2006 mass distribution of the nets and thus most mothers did not prefer using the nets on the new-born babies. The oval shapes only require one point to fix while the rectangular require four points and thus due to space the rectangular is not used in some houses Preferred color of the long lasting insecticide treated nets Color within the culture of the respondent has weight depending on the specific color which is being referred to. White color if associated to ceremonial occasions, red color associated with danger and black color associated with sadness. With its preference to the color of the net, 38% prefered blue, 37% prefered white while 25% prefered green as shown in Table 8. This was attributed to the fact that blue and green color do not show dirt and thus it will not be washed frequently but white color show dirt easily and thus it will have to be washed frequently. Comparing with the data on the frequency of the washing of the net and the insecticidal activity, the white net will loose its insecticidal actvity very quickyl due to frequent washing compared to the blue and green nets. Color has been an issue on the choice of the material from which the net is made. From the respondent 36.6% said they preferred a Blue color, 36.2% said white and 24.5% said green. The color green and blue were dominant against white due to their ability not to show dirt easily. Thus this means that the net owner will not wash the net frequently however.

76 Table 8: Presentation of Color of long lasting insecticide treated nets preferred by respondents. 63 Color preferred by PermaNet 2.0 Olyset % ( Percentage) the respondents. Blue % White % Green % Total % This compares significantly with the number of washes recorded at the households. The reduction of the washing of the nets also translates into saving of the soap and water which are scarce within the households sampled. White has also been held as a precious materials used only on certain occasion like weddings and funerals. During the focused group discussions the white nets were reserved for the guest in houses which had more than 3 nets. The fact that all those who had the bed nets had beds and that 93.7% of the nets were hanged over a bed was indicative of use of nets mostly over beds. The result of the qualitative study strengthens this. The reasons for such practice had been the health education given (which said nothing about using over a floor), practical problem of using the nets over floor (as nets easily adhere dust), norm of the area (despising those using it over a floor) and even the name of the net which includes the word bed. This should be a point of concern as many households, particularly in rural areas do not have beds Preferred method of preventing malaria Various methods have been used at the community level to prevent malaria through driving away mosquitoes. In this study the methods which were given as being used for malaria prevention were using Indoor Residual spraying, Doom, use of mosquito nets have been summarized in Figure 15 below.

77 64 From the respondents 70% LLINs are the best way of preventing malaria out of which 164/255 said that PermaNet 2.0 was the best LLIN compared to 91/255 of Olyset while 3.35% gave IRS as there prefered method. The low number can be attributed to the fact that most households did not understand what IRS was because it has not been used in the division. Though the responednt who said they knolw about IRS came from one division where IRS was used during the malaria control during floods operation, 7% said doom was the preferred method while 4% said draining stagnant water is the best method of preventing malaria. Figure 15: Response on how to prevent malaria. It was expressed that all the respondents and the people living around them use different methods of prevention. The commonest, mentioned by all groups are using mosquito net (69.5%), using mosquito spray (2.7%), using mosquito coil (3.0%) and avoid being bitten by mosquito (4.0%) through body movement like slapping the insect. Cleaning the environment had been exemplified by removing broken utensils, cleaning marshy areas, and cleaning the house as presented in Figure 15 above.

78 65 This results compare well with a study done to assess malaria prevention by mosquito nets in Burkina Faso, all respondents were interested in future use of treated nets, since they provide protection against mosquito(87%), only minority (3%) stated better protection against illness (Kroeger et al, 1999). In a social marketing program in Tanzania, the main motivation for use was mosquito nuisance rather than malaria control (Schellenber et al, 1999). Other factors might have also led to such dissatisfaction. One is the presence of P. vivax infection in considerable proportion. Where people cannot clearly know the difference between vivax and falciparum infections, malaria relapse can be taken as a re-infection. In fact most of the studies conducted pertaining to ITNs was in areas where P. falciparum infection by and large predominates. Another phenomenon is resistance to the previously widely used anti malarial drug (Sulphadoxine Pyrimethamine) which can lead to temporary clinical cure without parasitological clearance. According to a study in Kenya, a total resistance to treatment of 34.9% was found; with 18.5% failing within 14 days and another16.4% between 14 and 28 days after treatment (Ogutu et al, 2000) People having contracted malaria while using a long lasting insecticide treated nets The long lasting insecticide treated nets are supposed to protect the user from being beaten by mosquito and thus from contracting malaria. From the study only 20.46% of the respondent had not contracted malaria while using the mosquito nets while 79.54% had contracted malaria as shown in Figure 16 below.

79 66 Proportion of people having contracted malaria while using a Long lasting Insecticide treated nets. 100 respondents number of nets in the house Yes No Figure 16: Long lasting insecticide treated net users having contracted malaria. Number times a child have suffered from malaria Respondents Permanet Olyset 0 Not suffered Once Twice More than thrice Figure 17: Episodes of malaria within child under 5 years using the LLINs. Within the chidlren under 5 years, 20% had not suffered from malaria during the period in which they were using the net while 80% had suffered from malaria being 13% had suffered from malaria once 36% had suffered from malaria twice and 31% had suffered from malaria more than thrice.

80 67 Figure 18: Presentation on the knowledge of the respondent on symptoms of malaria. The understanding of the respondent on the symptoms of malaria was required to really understand whether the respondent could tell whether a child is suffering from malaria or not. From these variuos symptoms were received as outlined in Figure 18 above. After the symptoms the respondet gave variuos ways in which they knew malaria was being transmitted and the response summarised in Figure 19 below. Figure 19: Presentation on the response on how malaria is transmitted.

81 68 Quite a good proportion 44% knew that the only way of contracting malaria was through being bitten by a female anopheles mosquito while 49% gave various other ways which really do not lead to a child under 5years contracting malaria. However 7 % said they really did not know how malaria was transmitted to children under 5 years. The response show clear that a lot of awareness and the use of Information and Education materials on malaria prevention within the children under 5 years need to be enhanced. Perception that being in the sun, being rained on or chewing sugarcane are still being held by the community members as ways in which they can contract malaria Figure 20: Respondents answer on the treatment of malaria. As illustrated in Figure 20, quite a number of remedies were given to the child under 5 who is suffering from malaria. This ranged from giving traditional herbs to the conventional approved medicines. Even though some of the drugs have been shown to be ineffective against curing malaria community members still use them. These include drugs like Aspirin, Panadol, Chloroquine among others as outlined in the figure 20 above. Traditionally, adults, by virtue of their age and position as family income earners get priority coverage. The explanation is likely to be economical as well as cultural, as heads

82 69 are valued and are income generators of the house. Like the current finding, selling of nets had been observed in other areas. But use for other reasons like curtains appears to be uncommon. There are common reasons however that lead to either or both. Belief in the effectiveness of nets, appears to be behind both activities. There appears to be over expectation of prevention of malaria by the nets. Some expected absolute protection, even for adults. In reality, some who used the nets do develop malaria as infection might occur before going to bed (Rowland et al, 1996). It was found that 10.5% of bites were not prevented and those were mostly before dawn. Potential exposure occurs when people leave the bed to check on noise or urinate. People might not tuck in the net properly when returning (Brieger et al, 1996). Such failure of nets to render the required protection appears to let people sell them or use them for other purposes. Another reason for selling was of course poverty. Doubting effectiveness of nets within the respondents, however, led people to use them combat nuisance rather than avoid nets totally supporting the findings of a study to monitor community responses to malaria control measures in Nigeria, the proportion of people who perceived that mosquito net prevent malaria (22%) was less than those who believe in its prevention against mosquito bite (96%) (Brieger et al, 1996).

83 4.4 Objective 3: Household practices affect the mosquito knockdown of PermaNet 2.0 and Olyset nets sampled from household in Kadibo division Laboratory bioassay results Insecticidal efficiency of Olyset nets and PermaNet 2.0 were tested by using WHO cones. Assessments for KD3, KD60, and mortality after 24 hours were determined. Table 9: Results for the Bioassay for the PermaNet 2.0. Net Type 3 min 60 min 24hrs Sample N % Mortality N % Mortality N % Mortality Total exposed % % 10 25% % 6 15% % % 0 0% 3 7.5% % 0 0% 2 5% % 3 7.5% 3 7.5% % 3 7.5% 4 10% 40 TOTAL % % % 240 Mean SD Var Table 10: Results for the Bioassay for the Olyset. 3min 60 min 24hrs Sample N % Mortality N % Mortality N % Mortality Total exposed 1 2 5% 6 15% 4 10% % 6 15% % % 2 5% 4 10% % 2 5% 3 7.5% % 0 0% 3 7.5% % 0 0% 2 5% 40 Total % % % 240 Mean SD Var

84 71 Table 11: Results for the Bioassay for the SupaNet. Sample 3 min 60 min 24hrs Total exposed N % Mortality N % Mortality N % Mortality 1 2 5% 2 5% 2 5% % 2 5% 2 5% % 0 0% 2 5% % 0 0% 2 5% % 1 2.5% 3 7.5% % 1 2.5% 2 5% 40 TOTAL % % % 242 Mean Var Results presented in Table 9 11 shows very low mosquito knockdown and mortality in all replicates, with a very small number of mosquitoes knocked down at 60 minutes recovering later. In all the replicates a low percentage of mosquito mortality was realized with PermaNet, Olyset and Supanet recording 7.08%, 4.17% and 1.62% respectively for a 3 min mosquito exposure. Table 12: Knock Down after 3min chi-square analysis. Parameter Olyset PermaNet 2.0 Olyset Vs PermaNet 2.0 Sample 1 2/40 5/40 Sample 2 2/40 6/40 Sample 3 2/40 0/40 Sample 4 2/40 0/40 Sample 5 1/40 3/40 Sample 6 1/40 3/40 TOTAL 10/240 17/240 χ 2 =10.083, P=0.040 %Mortality 4.17% 7.08% Table 13: Knockdown after 60mins chi-square analysis. Parameter Olyset PermaNet 2.0 Olyset Vs PermaNet 2.0 Sample 1 6/40 7/40 Sample 2 6/40 6/40 Sample 3 2/40 0/40 Sample 4 2/40 0/40 Sample 5 0/40 3/40 Sample 6 0/40 3/40 TOTAL 16/240 19/240 %Mortality 6.7% 7.92% χ 2 = P=0.005

85 72 Table 14: Knock down after 24hrs Chi-square analysis. Parameter Olyset PermaNet 2.0 Olyset Vs PermaNet 2.0 Sample 1 4/40 10/40 Sample 2 5/40 9/40 Sample 3 4/40 3/40 Sample 4 3/40 2/40 Sample 5 3/40 3/40 Sample 6 2/40 4/40 TOTAL χ 2 = /240 31/240 P=0.032 %Mortality 8.75% 12.92% Claims have been raised in a study by Lindblade et al (in press) that, after a few months of household use, Olyset nets are no longer satisfactorily insecticidal. This claim arises from bioassay tests using WHO standard cones attached to the net and cardboard on the other side. This claim has thus been confirmed by these tests however the rates of mortality are too low compared to what had been reported earlier. In view of the results of the present project, the poor performance of Olyset nets in Lindblade's study was probably due to the bioassay employed, which would allow the mosquitoes' tarsae to be placed through the 4 mm holes of Olyset net on to the cardboard and not on the netting fibres. The tendency for mosquitoes to avoid touching the Olyset fiber might be partially caused by mutation to mosquitoes due to permethrin. Curtis et al (1999) and Miller (1994) emphasized the important effects of permethrin to Anopheles mosquitoes that permethrin and it is this pyrethroid which is incorporated into Olyset nets during manufacture. Tests in Cote d'ivoire of efficacy of Olyset nets showed deterrence to hut entry by An. gambiae (N'Guessan et al 2001). This emphasized the stimulus for mosquitoes to avoid Olyset netting. The problem of avoidance of net contact does not apply to ball frame assays as mosquitoes are forced to place their tarsae on the double layer of netting of the Olyset net. This presumably is reason for better

86 73 performance of wire frame bioassays as opposed to the unsatisfactory results on Olyset nets reported by Lindblade et a1 (in press) which may be considered an artifact of their cone method of testing. All other types of LLINs have smaller mesh and mosquitoes could probably not put their tarsae through these, so cone assays would probably give better results with small mesh nets. Tami et a1 (2004) evaluated Olyset nets used continuously for seven years in two different localities in Tanzania. Cone bioassays showed that mean mortality was 34 to 50%. This rather low score may have been partially because of the unsuitability of the cone method for bioassays of broad mesh nets. The diffusion of insecticides from inside the fiber of the net to the surface is temperature dependant. The manufactures of Olyset nets stated that the insecticide most diffused from inside the fiber to the surface. After each wash some of the insecticide is thought to be removed from the surface, but active ingredient will diffuse from inside after a certain period of time following washing and heating. The assumption in this statement was that there would be no any other source of heat where the net is hanged however during my study where 65% of the nets were used in a one roomed house with the cooking place at the end of the bed. This can accelerate the regeneration of the insecticides to the surface thus giving the poor performance of the LLINs after only 2 years of use. According to Hassan et al (2008) results on the retention of LLINs; it was found out that 92.9% of the LLINs had insecticide retention after one-and-half years after distribution. Some bed nets were distributed against a price. Utilization of bed nets by children less than five years of age and by pregnant women was found to be 55% and 42.1% respectively. For the bioassay efficacy tests, mean knock down after 60 minutes was 91.1%, while mortality after 24 hours was 99.4%. This compared differently with this current study which shows a low retention of the insecticide on LLINs. 12.9% on

87 74 PermaNet 2.0 and 8.7% on Olyset however utilization of the LLINs remain almost the same as the previous studies. 4.5 Objective 4: Accessibility and affordability of PermaNet 2.0 and Olyset nets within households in Kadibo division Table 15: Where the respondent obtained the Long Lasting Insecticide Treated nets. Where the net was PermaNet 2.0 Olyset % obtained. Retail shop % Local Pharmacy 5 9 5% Health center/clinic % Market % Donation from NGOs % Total % A further insight to group the source of the LLINs confirmed that 24% got their nets from the local shop, 5% from pharmacy, 52% from health center and clinic, 10% from the open air market, 9% from donations from well-wishers and NGOs as outlined in Table 15. This still affirm to the earlier figures that most of the nets were acquired from the health centers mainly through the Maternal and Child Health Programme at the Health facilities. Though there were a lot of emergency programmes which had been implemented during the flood operation, only 9% of the respondents attributes their net ownership to these operations.

88 Table 16: A comparison of the prices of the Long Lasting Insecticide Treated nets. Price of the net (Ksh ) I don t know % % % % % % 501 and above % Total % 75 PermaNet 2.0 Olyset % Table 16 illustrates the various prices of the nets at the community level with 53% reported to have paid Ksh which tally with the mode of acquisition of the nets. The Ministry of Medical Services under Maternal Child Health programme, the nets cost Ksh 50 as a cost sharing. Out of the interviewed respondents, 15% reported to have acquired the net by paying over Ksh 501. PermaNet 2.0 nets cost more than the Olyset however, with the support of the government and some organizations such as UNICEF, Olyset bed nets are provided free to the population within the routine MCH programmes at the health facilities. The fact that some households have re-impregnated the nets in the belief that they do in fact need to be re-impregnated raises once more questions about the messages delivered by those who distributed the nets. It also raises questions about the identity and experience of those who conduct and provide for the re-impregnation of the nets.

89 76 These activities were conducted, according to the focus group discussions, by some NGOs. Figure 21: Respondents' perception on the price of the LLINs. Figure 21 above shows the perception of the respondent on the prices of the net. Out of the interviewed respondents, 30% had no comments because they received the nets through donation; 24% said the prices at the health center are too high. This mainly translated to the sample that did not have a substantial source of income and was living below one dollar a day; 24% said the price was affordable; 21% said the price was low and need to be raised to realize sustainability of the program at the health facility. The awareness about the factory treated nets was also evident with 98% of the respondent saying that they were aware that the mosquito nets they were using are already treated with the insecticide. However, still there were respondents who did not know that the net had been treated. About their knowledge on the Long lasting insecticide treated nets, 68% had knowledge on what Long lasting Insecticide treated nets are and that they need no retreatment however 32% still re-treated the net after washing.