Residual Soil-Transmitted Helminth Infection Among School-Aged Children in an Urban Informal Settlement of Nairobi, Kenya Prevalence, Species Distribution, and Associated Factors
Main Article Content
Abstract
Soil-transmitted helminths (STH) remain an important public health challenge across sub-Saharan Africa, particularly for school-aged children, and transmission may continue in crowded urban informal settlements despite Kenya's school-based deworming programme. This study set out to establish the current prevalence and species composition of STH infection and to examine the sociodemographic and water, sanitation, and hygiene (WASH) factors associated with infection among school-aged children in Pumwani, Nairobi. A descriptive cross-sectional survey enrolled 372 children aged 5–11 years, selected through two-stage cluster sampling from three public primary schools. A single Kato-Katz thick smear was used to examine each stool specimen, and structured questionnaires captured sociodemographic details, household WASH conditions, and deworming history. Associations were tested using Pearson's chi-square and Fisher's exact tests. The overall prevalence of STH infection was 19.4%, with Ascaris lumbricoides most common (15.6%), followed by Trichuris trichiura (4.3%); no hookworm was detected. Younger age (p = 0.0014) and lower grade level (p = 0.0024) were significantly associated with infection, whereas sex, parental education, WASH indicators, and deworming history were not. STH infection, therefore, persists in this informal settlement despite reported deworming coverage, with the heaviest burden among the youngest children. Sustained control is likely to require an integrated approach combining preventive chemotherapy with WASH improvements and school health education, and further work using multivariable analysis and more sensitive parasitological methods is recommended.
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