An Experience with Dengue in Pakistan: An Expanding Problem

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1 Ibnosina J Med BS 3 ARTICLE An Experience with Dengue in Pakistan: An Expanding Problem Shazia T. Hakim 1,4, Syed M. Tayyab 1, Shams U. Qasmi 3, Sayyada G. Nadeem 2 1. Virology & Tissue Culture Laboratory, Department of Microbiology, Jinnah University for Women, Karachi-74600, Pakistan. 2. Mycology Research & Reference Institute, Department of Microbiology, Jinnah University for Women, Karachi-74600, Pakistan. 3. Med Path Laboratories, Karachi, Pakistan 4. Burgor Anklesaria Hospital s Pathological Laboratory, Karachi, Pakistan *Corresponding author: Shazia T. Hakim Shaz2971@yahoo.com Published: 01 January 2011 Ibnosina J Med BS 2011, 3(1):3-8 Received: 05 September 2010 Accepted: 27 October 2010 This article is available from: This is an Open Access article distributed under the terms of the Creative Commons Attribution 3.0 License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Introduction: Emerging infectious diseases pose threats to the general human population including recipients of blood transfusions and health care workers. Dengue is an expanding problem in tropical and subtropical regions. It is now the most frequent arboviral disease in the world, with an estimated 100 million cases of dengue fever annually, 250,000 cases of dengue hemorrhagic fever, and 25,000 deaths per year (1). Materials & Methods: A total of 459 blood serum samples were collected from suspected patients of dengue fever, aged 10 to 65 years, from different parts of the city, at two different Pathological Laboratories of the city and were subjected to hematological, biochemical and serological analysis using standard laboratory procedures including Enzyme Linked Immunosorbent assay (ELISA) for the determination of Dengue specific IgG and IgM antibodies. Results: Out of 459 blood samples 289 (63%) were confirmed as having significant dengue IgM antibody titer and dengue IgG antibody titer in 193 (42%) patients. Conclusion: This paper discusses the need of an appropriate framework for approaching the environmental control of Dengue virus/dengue Fever/Dengue Hemorrhagic Fever with reference to the current situation of the flooding and flood related disasters in a resource limited country such as Pakistan. This is the time to evoke a sense of moral indignation at unnecessary suffering and for the leadership to mobilize human will power and resources to take on the task of controlling emerging infectious diseases like malaria and dengue. Key Words: Dengue, Dengue Hemorrhagic fever, transmission, control, flood. Introduction Dengue virus/ Dengue Fever/ Dengue Hemorrhagic Fever is found mostly during and shortly after the rainy (monsoon) season in tropical and subtropical areas of Africa, Southeast Asia and China, India, Middle East, Caribbean and Central Ibnosina Journal of Medicine and Biomedical Sciences (2011)

2 Hakim ST et al An Experience with Dengue in Pakistan 4 and South America, Australia and the South and Central Pacific (1,2). In Pakistan, the first documented report was in 1985 (3) whereby Dengue type 2 virus was isolated in a seroepidemiological study for encephalitis. The first major outbreak was reported in Karachi in (4,5). Through mid-2005, patients with DF or DHF were admitted each year to a tertiary care referral center in Karachi. Many more cases, however, may have gone unrecognized. From September through December 2005, at least 3 major hospitals in Karachi had a sudden increase in the number of patients with signs consistent with the World Health Organization definition of DHF: high fever, rash, epistaxis, gum bleeding, liver dysfunction, and thrombocytopenia (platelets <100,000/mm3). Most of the cases had evidence of capillary leakage in the form of raised hematocrit and pleural effusion with or without ascites (6). Another Epidemic has been witnessed in Karachi following heavy rain-falls in 2006 affecting about 4,750 people and claiming 50 lives over a period of about six months (7). Recent trends have shown that DF in Southeast Asia causes cyclical epidemics every 2 to 3 years. A change in prevalence of serotypes has also been noticed during these recent outbreaks, as DEN-3 has become more prevalent Table 1: Laboratory Findings in Suspected Patients of DF/DHF (N=459) Tests Normal Range Diagnostic Value Number of Positive Patients; %age % positive or abnormal out of the population *with serologically confirmed DF/DHF*. (n = 289) Hematocrit Value % > 52 % 260; ; 93 Leukocyte Count x 10 9 /l < 3.0 x 10 9 /l 254 ; ; 88 Neutrophil Count % < 45 % 167 ; ; 58 Platelets Count x 10 9 /l < 100,000/cmm 289; ; 100 Prothrombin Time Sec > 20 seconds 215; ; 74 Blood Urea Nitrogen (BUN) 8-18 mg/dl > 20 mg/dl 200; ; 69 Raised Liver enzymes ALT/ AST - 212; ; 73 a) ALT 3-30µ/l >35 µ/l 33; 11 13; 4 b) AST 6-33 µ/l >38 µ/l 61;21 61; 21 c) ALT + AST ; ; 41 Serum IgA level x 10 mg/dl <1.7 x 10 mg/dl 284; ; 98 C3 Level mg/dl <70 mg/dl 243; ; 84 Occult Blood in Stool Negative Positive 105; ; 36 ISSN: X

3 Ibnosina J Med BS 5 Table 2: Serological Findings of DF/DHF in Suspected Patients. (N= 459), on the basis of Dengue specific antibodies. Tests No. of Negative Patients; %age No. of Positive Patients; %age Rapid Immunochromatography 170; ; 63 IgG antibodies (ELISA) 263; ; 43 IgM antibodies (ELISA) 170; ; 63 Both IgG+IgM antibodies (ELISA) 335; ; 27 than DEN-2 serotype (8). There is now evidence that cocirculation of DEN-2 and DEN-3 was responsible for the 2006 out-break (9). The virus hit the city again in 2007 with more than 2,600 people reported at major government and private hospitals and about 22 succumbed to it. Because of the comparatively increased awareness among people about the signs and symptoms of dengue, it has been observed that in the following year, the mortality rate due to dengue appeared to be considerably lower as the health authorities confirmed only few deaths. The present study is a collection of seroprevalence rate of dengue suspected patients from two Table 3: Prevalence of Suspected DF/DHF Patients (N=459) in Different Months of the Year Starting June 2009 to June 2010 No. of Suspected Patients No. of Confirmed DF/DHF %age of Suspected Year Month (N=459) Patients (N=289) Patients June July August September October November December January February March April May June Ibnosina Journal of Medicine and Biomedical Sciences (2011)

4 Hakim ST et al An Experience with Dengue in Pakistan 6 different pathological laboratories of the city, which will help us determine the preventive behavior of the population of the city. Other important features of this study include hematological, biochemical and serological patterns of the disease among suspected and confirmed dengue patients. Materials and Methods The study was conducted during the period of June 2009 to June A total of 459 blood samples were collected from suspected patients of dengue fever, aged 10 to 65 years, from different parts of the city, using two different Pathological Laboratories. Signed informed consent forms were obtained following Institutional Review Board policies of the respective institutes. All 459 patients had health checkups by a medical doctor before collection of specimens, they were asked about any history of fever, mosquito bites, jaundice, blood transfusion and their platelet counts were determined. Following the completion of history abd physicals, patients were requested to give 5mL of blood for different hematological screening tests including complete blood picture (CBP), hemoglobin percentage (Hb%) and erythrocyte sedimentation rate (ESR), 5mL of blood for different biochemical parameters including blood urea nitrogen (BUN), and liver enzymes, and 5 ml of blood was collected for serological tests to check the presence of total albumin, C3 level and IgM and IgG antibodies against dengue virus using rapid immunochromatography kits (Acon), and Confirmatory test by using ELISA. Occult blood in stool samples of the said patients and prothrombin time was also noted. Results Blood samples of suspected cases of Dengue infection (N=459), received during June 2009 to June 2010 at two different pathological laboratories were included in this study. More samples were collected in the months of August, September, October and November with the highest numbers in October In a total of 459 suspected cases, 289 (63%) were confirmed of having low platelet counts (100,000/cmm or less) in 289 (100%), raised hematocrit values (>52%) in 260 (90%), decreased leukocyte count (<3.0) in 254 (88%), decreased neutrophil count (<45) in 167 (58%), hypoalbuminemia (< 1.7 x 10 mg/dl) in 284 (98%), elevated BUN (> 20 mg/dl) in 200 (69%), raised liver enzymes in 212 (73%) with ALT > 35µ/l and AST > 38µ/l, positive occult blood in 105 (36%), and prolonged prothrombin time (>20 seconds) in 215 (74%) patients (Table 1). Out of 459 blood samples 289 (63%) were confirmed to have significant dengue IgM antibody titer and dengue IgG antibody titer in 193 (42%) patients. Decreased C3 level (<70 mg/dl) was noted in 243 (53%) patients. Out of 289 confirmed dengue fever cases, 124 (43%) were reported as confirmed dengue hemorrhagic fever (DHF) cases on the basis of positive dengue IgM antibody titer, decreased total leukocyte count (<3.0), low platelet count (<100,000/cmm), and long prothrombin time i.e. > 20 seconds (Table 2). Seroprevalence of dengue fever or dengue hemorrhagic fever was mainly observed in the middle aged group patients of age between years of age, most of the patients were male i.e. 376 (82%) out of the total 459 suspected cases of dengue. Discussion Dengue fever is mostly a rather undifferentiated febrile disease with non-specific signs and symptoms. Molecular and serological tests are used to confirm the clinical diagnosis. In Karachi alone we have approximately 150 registered hospitals and pathological laboratories and several other unregistered laboratories. Out of these only 10% of the laboratories have facilities available for serological confirmation of dengue by commercially available assays. As per our knowledge, most of these laboratories are using rapid immunochromatography kits and Enzyme Linked Immuno Sorbent Assay (ELISA); only 6 of them have facilities for polymerase chain reaction (PCR) based diagnosis of dengue. Samples from rural areas and less developed cities have to be sent to laboratories in Karachi, Lahore or Islamabad. The applicability and quality of serological tests in dengue endemic regions has to be judged against a background of potential cross reactivity with other flaviviridae, difficulties in distinguishing primary from secondary infections and technological problems are present and related to the fact that most dengue endemic regions are relatively poor of resources (9). Early diagnosis on the basis of clinical picture and history of mosquito bite is helpful but appropriate serological diagnosis for the DF/ DHF is more important particularly with reference to quick treatment procedure as it is evident that the patient may die within hours if not treated promptly (10). Our findings shows that the seroprevalence ratio of dengue among the suspected population of Karachi, on the basis of clinical appearance is 63% (i.e. 289 out of 459 cases), Out of these 289 cases platelet count was found below normal range in all patients (100%), Lecukocyte count was low in 254 (88%), while raised ALT/ AST level was observed in ISSN: X

5 Ibnosina J Med BS (73%) patients. Another important finding was raised serum IgA level in 284 i.e. 98% patients. (Table 1). In communities with least available facilities for the diagnosis of infections like DF/ DHF, these parameters can be of very much importance and can be used as criteria for treatment. There are sporadic cases throughout the year, with maximum number (130, 28.32% cases) observed in the month of October, after rainy season (monsoon season) i.e. during June to September (Table 3). Due to ambient temperature and humidity in the environment, this period is supposed to be ideal for mosquito breeding (11,12). The deadly mosquitoes mainly affect heavily crowded locations of the city along with slum areas. During this study maximum suspected cases were of the male gender, which may be attributed to of the fact that in Asian culture, comparatively, males spend more time outside their houses and thus are more likely to be exposed when compared to females (13-15). Ahmed et al, have also reported the incidence of dengue more in males than in females (7). In recent years the average annual incidence of denguerelated serious disease in many tropical countries has been rising dramatically, with the infection becoming endemic in cities where its occurrence was once sporadic (16). The reasons for this are complex and not fully understood. A variety of factors are likely to be important, including human population growth and increased aggregation in urban areas. Also of importance is an increased frequency of travel between cities and countries, and failures in public health measures such as mosquito vector control in urban slum areas in infected regions and deterioration of Public Health infrastructure. In conclusion, Pakistan is currently facing the worst flood in the history. A number of infections associated with rain and flood have started to appear in different parts of the affected areas. Dengue and malaria are among the top most infections related to mosquito breeding in these areas. We should worry about the after effects; the plan for recovery phase should be prepared and launched very tactfully. Two crucial factors which may contribute to the dengue control are: (1) Involvement of educational institution to solve the problem via creating awareness through lectures, symposia, written material etc. (2) Involvement of vocal citizen groups to raise their voices against this alarming situation of increased incidence in a variety of infections due to contaminated water, improper sewage disposal, and accumulation of waste water at different places. Mosquito control can only be achieved by the destruction of mosquito breeding sites. It is suggested that at least 11 sectors of our society can take some interest in or responsibility for the control of dengue and other mosquito associated infections. For example: national health ministry, city health department, environment protection agencies, urban planning division, department of justice, department of education, ministry of science and technology, the media, private/ corporate sector and people themselves (17,18). These challenges posed by DF/ DHF, a hazardous disease, will only are met if society comes to recognize that the education of every level of the community and the use of every medium should be undertaken. Besides this, adverse effects of global warming on human health can be prevented by research, rebuilding public health infrastructure and by developing and implementing effective prevention strategies of infectious diseases. We believe that a multimodality outreach and timing are keys to control this public health problem. Acknowledgement Authors are grateful to the administration of Jinnah University for Women, Dr. Shams ul Arfeen Qasmi, Dr. Dorab Anklesaria and Mr. S. M. Humair Tayyab for their technical support and cooperation throughout the study. References 1. Gubler DJ. The global emergence/resurgence of arboviral diseases as public health problems. Arch Med Res 2002;33: Chaturvedi UC, ShrivastavaR. Dengue Hemorrhagic Fever: A Global Challenge. Indian J. Med. Microbiol 2004;22: Qureshi JA, Notta NJ, Salahuddin N, Zaman V, Khan JA. An epidemic of Dengue fever in Karachi. associated clinical manifestations. J Pak Med Assoc 1997;47: Vijayakumar TS, Chandy S, Satish N, Abraham M, Abraham P, Sridhavan G. Is Dengue emerging as a major public health problem? Indian J Med Res 2005;121: Gubler, D. Dengue and dengue hemorrhagic fever. Clin. Microbiol. Rev 1998;11: Page, RDM, Holmes EC. Molecular evolution: a phylogenetic approach. Oxford: Blackwell Science; Ahmed S, Arif F, Yahya Y, Rehman A, Abbas K, Ashraf S, et al. Dengue fever outbreak in Karachi a study profile and outcome of children under 15 year of age. J Pak Med Assoc 2008;58: Gurugama P, Garg P, Perera J, Wijewickrama A, Seneviratneet LS. Dengue viral infections. IJD Ibnosina Journal of Medicine and Biomedical Sciences (2011)

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