Influence of human demographic Characteristics on Soil Transmitted Helminthiasis in Nsukka zone, Enugu State, Nigeria

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1 Influence of human demographic Characteristics on Soil Transmitted Helminthiasis in Nsukka zone, Enugu State, Nigeria Onuoha, E.O 1 *., Ofoezie, I.E 2. and Eyo, J.E Department of Zoology, University of Nigeria, Nsukka, Nigeria. 2. Institute of Ecology and Environmental Studies, Obafemi Awolowo University, Ile-Ife, Nigeria ABSTRACT The study examined the effect of selected demographic variables, namely marital status, sex and age on the prevalence and intensity of soil-transmitted helminthiasis in Nsukka zone, Enugu State, Nigeria. Fifty households were systematically selected in eleven randomly selected communities in Nsukka zone. A structured questionnaire was administered to selected people to obtain information on their marital status, age and sex. Faecal samples were collected from each person and analyzed for presence and intensity of helminthes egg per gram of faeces (epg) using modified Kato Katz method. Hookworm and ascariasis were the only soil-transmitted helminth infections observed in the area. The overall prevalence of hookworm (Ancylostoma duodenale and Necator americanus) infection was 50.0% in males, 55.0% in females and 30.5% to 82.6% in 40+ and years age groups respectively. For ascariasis prevalence was 69.5% in males, 71.9% in females and % in bracket age and years age brackets respectively. Intensity of hookworm ranged from ±141.5 (epg) in males to 128.9±134.9 epg in females, and 76.2±126.7 to 198.8± epg in the 40+ and years age group respectively. For ascariasis, the values were 288.3±238.4 in males, 328.5±237.7 in females, and 237.7±229.0 to 396.3±234.5 in 40+ and 19 years old age groups respectively. For marital status, prevalence of hookworm ranged from 36.3% to 70.1% among the married and single persons, respectively while that of ascariasis ranged from 61.5% of 81.4% among the widower and single persons respectively. These differences were significant at 5% error margin. Keywords: helminthiasis, Nsukka zone, age, sex, marital status, faecal sample *Corresponding: econuohaunnyahoo.com Phone: INTRODUCTION Soil transmitted helrninthiasis are common in Nigeria. The most widespread included Ascaris lumbricoides Trichuris irichiura, Ancylostoma duodenale, Necator americarnis, Strongyloides stercoralis, Enterohius vermincularis and Toxocara species. A duodenale and N. americanus which together cause hookworm infection and Strongvloides stercoralis are transmitted by direct skin penetration while the rest gain entry by oral route (Chandler and Read, 1961; Crompton and Pawlowski, 1985; Cheeesebrough, 2006). The morphology and pathology of these helminthes are well known (Klement et al, 1996; Humar, 1983; Dobardzic et al. 2002; Hawdon, 1996). Although many of these infections have been identified by several authors in Nsukka zone, few have described the detailed effect of human demographic factors such age, sex and marital status on there epidemiology. Understanding the influence of age is particularly vital because aging is a complex and dynamic process with intricately interrelated and inseparable physiological, psychological and sociologic components. There is a great difference between the young and the old. Most old people have progressively poor sight, failing memory, poor sense of smell and failing strength. The young are careless. Martial status influences eating habit while sex influences nature of job. These factors may affect rate of disease transmission. This paper presents the influence of age, sex and marital status on the prevalence and intensity of hookworm and ascariasis with an aim of identifying weak points that might serve as targets of effective control delivery and monitoring.

2 76 Onuoha, E.O (Vol ): Influence of Human Demographic Characteristics MATERIALS AND METHODS STUDY AREA The study was carried out in eleven communities within Nsukka zone between 2006 and The zone is located about 64 km Northwest of Enugu, approximately on longitude 6 30 and 7 60 N, covering an area of over 60,100 km 2. The eleven communities selected in the area are Edem Road, Ezeopi, Akpugoeze, Fulton, Margret Cartwright, Nkpunato, Ogurugu, Site Road, New Anglican Road, Uvuru and Nkpologu. The annual precipitation in the zone is about 1600mm while the mean temperature is 27 C (Nwafor et al., 2001). SAMPLING AND TOOL OF STUDY Selection of subjects for the investigation was based on 50 households from each community and four individuals per household. The households were selected systematically and individuals randomly. An informed consent of the selected persons, their household heads and community leaders were sought and obtained before each person was administered a structured questionnaire through a participatory approach. The questionnaire obtained demographic information on age, sex and marital status as well as the person s knowledge and awareness concerning mode of transmission and health implications of soil- transmitted helminth infections. A specimen bottle was assigned to each subject completing the questionnaire after an advice on the most hygienic technique for collecting faecal sample. Some of the subjects returned the samples immediately while a few returned theirs the next morning. Each faecal sample was fixed in 10% formaldehyde, returned to the laboratory, and analyzed for presence and number of helminth eggs. Two grams of each sample was aseptically transferred to a 250 ml flask containing 60 ml of saturated sodium chloride solution, homogenized and sieved with a sieve of 250 mesh size. A 0.3 ml of the homogenized suspension was transferred into a two-chamber McMaster slide and viewed under the microscope to determine the presence, type and number of soil-transmitted helminth parasites in each sample. The total number of eggs of any identified helminth parasite in each chamber was counted under x40 magnification of a compound microscope and multiplied by a factor of 100 to convert to eggs per gram (epg) of faeces (Krecek, 2004). STATISTICAL ANALYSIS Analysis of sex related intensity among the different age groups showed that intensity of each infection and combinations of infections were girls were. Data were analyzed statistically and reported as percentages for prevalence and mean±standard deviation for intensity of infection. Comparison of prevalence was made using the chi square values from the Contingency tables while intensity of infection was analyzed using the Student t-test for dichotomous variables and One way analysis of variance (ONEWAY) for explanatory variable with more than two levels (Zar, 1992). RESULTS Prevalence and intensity of infection by Age and Sex The pattern of distribution of prevalence and intensity of hookworm and ascariasis in relation to age and sex of subjects examined in the eleven communities are presented in Table I. Of 906 males and 1145 females examined, 453 (50.0%) and 632 (55.2%), respectively were infected with hookworm; while 69.5% and 71.9% were infected with ascariasis. 47.5% and 34.5% of the subjected carried double infection while overall, % had at least one infection. For all infection combinations (i.e. single, double and at least one), prevalence was very significantly higher (p<0.00i) in females than males. For both hookworm and ascariasis and their combinations, peak prevalence was attained in the first decade of life (0-9 years age group) in males, and second decade (10-19 years) in females. That is, prevalence was attained earlier in males than females, and among males, decreased gradually from peak in first decade of life to its lowest level in the oldest age group. Among females, however, it increased gradually to a peak in the second decade of life before decreasing to lower levels in the subsequent age groups. Age-dependent infection patterns of both infections and their combinations were also highly significantly (p<0.00i) different between males and females. Intensity of both hookworm and ascariasis infection and their combinations was higher in females than males but while this difference was significant (p<0.0i) for ascariasis, double and at least one infection, it was comparable for hookworm. Like prevalence, intensity pattern was also age dependent (p<0.00i), with peak intensity among males occurring in the 0-9 years age bracket and that among females in the years age group. higher among females than males in all age brackets except in the 0-9 years old age group where boys were more heavily infected than

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5 Onuoha, E.O (Vol ): Influence of Human Demographic Characteristics 79 DISCUSSION This Investigation revealed hookworm and ascariasis as the two most common soil transmitted helminthes infections in Nsukka zone. It also showed that the two infections were widespread and people of all ages, sex and marital status were vulnerable. In all the communities, the ascariasis infection was more common. The pattern of distribution of prevalence and intensity of hookworm and ascariasis infections were Ibund to be age and sex dependent. More female were infected: hookworm (55%), ascariasis (71.9%) and less male were infected hookworm (50%) and ascariasis (69.5) The margins were not much. These could be explained on the ground that female were more engaged in domestic and petty farm work hence more vulnerable to the infection. The peak prevalence of all the infection was attained in the first decade of life in males, and second decade of life in females. The prevalence peak was attained earlier in males and decreased gradually in the subsequent ages. The age dependent was significantly high (p<0.oo I). Male children are earlier used for farm work, other field involving projects and play a lot in the playground which might lead to earlier encounter of the infection than the female children. From the findings, children were more affected. They have tender skin, and larvae penetration might be easier. Children play more than the adults and such play involved direct contact with the soil. Then eating habit was equally poor and these factors contributed to rapid rate of infection. As these kids are growing their life will change and these contributed to the decline in the inflection rate as observed. The peak of the prevalence of the infection in females was years. This was the age female early engagement in farm work and other field project was highest and they have sound knowledge of hygiene and could easily be infected. The prevalence and intensity of the infection were more in the people that were single. These findings supported that the rate of infection was age dependent and more in children that constituted more of the single persons. Married, devoiced, widows and widowers constitute the older age and were less infected. REFERENCE Chandler, A.C. and Read, C. p. (1961). Introduction to Parasitology. Weilly and Son mc, New York, 820 pp. Crompton, D.W.T and Pawlowski, Z.S (1985). Life History and Development of Ascaris in lumbricoides and the persistence of human ascariasis. In: Crompton, D.W.T., Nesheim, M.C. and Pawlowski, Z.S edn, Ascariasis and its Public Health.Significance. Taylor and Francis, London, 9pp. Dobardzic, R, Aotez, P.J and Dobardzie A (2002). Hookworms ( Ancylostoma duodenale and Necator americanus In: Yu V.L, Weber, R and Raon A. (edn) Antimicrobial Therapy and vaccines. Apple Trees Production Ltd, New York, 1543pp. Hawdon, J. M. (1996). Difference between the human hookworms Ancylostma duodenale and.necator americanus using PCR-RELP. Journal of Parasitology 82: Humar, S. (1983). The response of adult and free-living stages of Necator americanus, in vitro to anthelmintics. Revue de Biologic Tropicale 35 : Klement, P., Auguatine, J. M. Deleney, K. H., Klement, G. and Weitz, J. L., (1996). An oral ivernectin regimen that eradicates pinworm (Syphaciaspp.) in Laboratory rats and mice. Laboratory Animal Science 46: Nwafor, J.C., Bob-Duru, R.C. and Anyadike, R. N. C. (2001). Geographical Reports of the University of Nigeria Nsukka. Fulladu Publishing Company, Nsukka, 169 pp. Zar, J. H. (1992). Biostatistical.Analvsis. 2 nd ed. Prentice- Hall, Eaglewood Cliffs, New Jersy. 718 pp.