Prevalence and Associated Risk Factors of Intestinal Parasitic Infections in Oloisukut Conservancy Community, Narok County, Kenya

Abstract

Globally, approximately 1.4 billion people suffer from soil-transmitted helminth infections with disease burden estimated at 5.3 million Disability Adjusted Life Years. Mass drug administration (MDA) remains the World Health Organization recommended control strategy. In 2012 the Kenya government initiated a national school-based deworming program (NSBD) among school children living in high-risk environments. This program however, faces the challenge of re-infections with the factors leading to this being poorly understood. Furthermore, the program neglects non-school age children and adults who may serve as potential reservoirs of infections within the community. A cross sectional community-based descriptive study was conducted to determine the prevalence of intestinal parasitic infections (IPIs) and its associated risk factors among the community living in Oloisukut Conservancy, Trans Mara, Narok County, Kenya. Human fecal samples were collected and microscopically examined for detection of intestinal parasites using the Kato-Katz and formal-ether concentration techniques prior to treatment with mebendazole. A total of 411 fecal samples from family members aged ≥ 2 years and representing 92/483 families were collected and examined. Structured questionnaires were administered to determine risk factors associated with IPIs. Results from stool examination were linked to questionnaire responses. Univariate and multivariate analysis in a random mixed effects logistic regression model and described as odd ratio (OR) were used to examine the relationship between IPIs and associated risk factors. A p<0.05 was considered significant in all analysis. The prevalence of IPIs was 62.5% at baseline and 53.9% at endline survey. Prevalence of intestinal protozoa and helminths was 46.2% and 39.9 % respectively. Eleven genera of intestinal parasites were observed at baseline survey. The intestinal helminths observed were T. trichiura (36.7%), followed by A. lumbricoides (5.6%), Hookworm (2.7 %), H. nana (1.2%), Taenia spp. (0.7%) and S. stercolaris (0.2 %). The intestinal protozoa observed were E. histolytica/E. dispar/E. moshkovskii (31.6%) and G. lamblia (9.7 %). Non-pathogenic protozoa observed were E. coli (24.6%), I. buetschlii (8.5%) and C. mesnili (1.0%). More males compared to females were infected with IPIs. School going children (5 -14 years) bore the highest burden of infections. Polyparasitism was more prevalent (35.3%) compared to single infections (27.3%). STH prevalence decreased from 39.9% at baseline to 19.2% at end line, with a relative reduction rate of 58.4%. Age was the only risk factor linked to IPIs in this study. The presence of Taenia spp. is suggestive of zoonotic transmission within this community. Based on the high prevalence of helminth infections among community members typically not targeted by the MDA national deworming programs, this study recommends inclusion of the entire community in preventive chemotherapy intervention within the national NTD elimination and deworming programs. This study further suggests the need to integrate management of intestinal protozoan infections with the national deworming programs.