Prevalence of haemoparasitic infection in humans and insect vectors in Yenagoa, Bayelsa State, Nigeria

Abstract

The preliminary investigation was conducted to determined the occurrence and transmission of heamoparasites and their insect vectors in two communities of Yenagoa (Agudama and Azikoro), Bayelsa State, between September 2004 and March
2005. 2 mls of intravenous blood was collected from 200 individuals. Thick and thin blood smears and Knott\'s concentration methods were utilized after staining in dilute giemsa solution. 81 (40.5%) of the sampled individuals were positive for different haemoparasites. Of the number positive, 60 (30.0%) were plasmodium falciparum, while 21(10.5%) were micro-filariamic. The different micro-filariae recovered were, 3 (1.5%) Wuchereria bancrofti, 3 (1.5%) Loa loa, and 15 (7.5%) Mansonella perstans. The prevalence rate of the haemoparasites was higher in Azikoro, (46.8%) than in Agudama (34.9%). Differences in the
prevalence rates between the two communities was not statistically significant (p-value = 0.013357) (p>0.05). More females with 54 (40.9%) were infected than males, with 27 (39.7%), although, the difference in prevalence was not statistically significant (p-value = 0.86957) at 5% level (p>0.05). Infection was highest in 30-39 years age group with 17 (77.3%) and least in 70+ years age group with 1 (11.1%). The variation in age-related prevalence of haemoparasites was statistically significant (p-value = 0.0000068) (p<0.05). Insect vectors identified were Anopheles gambiae sl, A. nili, A. funestus, Culex, Aedes aegypti and Culicoides species. 28 (17.4%) of the insect vectors were infected with different haemoparasites. 24 (14.9%) of A. gambiae sl and A. nili were infected with sporozoites of Plasmodium, while 1 (2.1%) of Culex species was infected with W. bancrofti and 3(20.0%) of Culicoides species were infected with M. perstans. The result of the study indicates the presence of heamoparasites in Yenagoa communities and the control of these parasites and their vectors is advocated.

Keywords: prevalence, haemoparasites, infection, insect vectors, Yenagoa, Nigeria.

Nigerian Journal of Parasitology Vol. 29 (2) 2008: pp. 131-135