Prevalence Study of Intestinal Parasites Among Patients Attending Health Centers in Nairobi

Abstract

The prevalence study of intestinal parasites presented here involved 592 out-patients of whom 310 (52.4%) were males and 282 (47.6%) were females, at three City Council health centres in Nairobi. The age ranged 1 year to 71 years, with a mean of 24.8 years. Fresh stool samples were collected in pre-labelled plastic containers from the study population and examined for intestinal parasites using three methods: direct smear in normal saline, formol-ether concentration and modified Zeihl-Neelsen staining technique for detecting Cryptosporidium sp. A standard questionnaire was administered to each patient to obtain information on their ethnic background, age, sex, duration of stay in Nairobi, water source, toilet facilities and level of education. The overall parasitic infection rate was 56% (332/592) in which 57.2% (190/332) of the infected participants had multiple infections. Of the 332 patients infected with parasites, 238 (71.7%) harboured protozoa only, 41 (12.3%) had helminths only and 53 (16%) were infected with both protozoa and helminths. The most common protozoal infections were: Entamoeba coli 165 (27.9%), Endolimax nana 111(18.7%), Entamoeba histolytica 93(15.7%) and Blastocystis hominis 63 (10.6%). Helminthic infections were much less prevalent than protozoa. The most prevalent helminths were: hookworm sp 43(7.3%), Ascaris lumbricoides 27(4.5%) and Trichuris trichiura 21(3.5%). The most infected age groups were 21 - 25 and 26 - 30 years old. Drinking of unboiled water was strongly associated with both protozoal (X2 = 10.8; P<0.001) and helminthic infections (X2 = 16.3 ; P<0.001) The high parasitic infection rate and the frequency of multiple infections may suggest an interrelationship of environmental, hygienic and socio-economic factors which support transmission rather than single factor. The results of this study emphasises the need to carry out a prevalence studies on intestinal parasites from time to time to enable health planners to improve sanitary condition of the community.