Study on the distribution of parasitic infections in western Kenya, in order to improve deworming programs and their evaluation

Since 2012, a national school-based deworming programme has provided preventive anthelminthic treatment to over 6 million Kenyan children annually. While this control strategy reduces overall infection levels, infection bounces back soon after treatment administration. In order to improve the efficiency of control programmes, both improved diagnostic tools and further knowledge on the factors driving reinfection is still required.    

This field study, conducted in 2014 in western Kenya, investigated the clustering of STH infections at the village and household levels. A cross-sectional survey was conducted in four rural villages near Bungoma Town, targeting over 1000 residents from 2-81 years of age. Epidemiological data were collected at two time-points, at study baseline and three months post-treatment with 400mg albendazole. Stool samples were analysed using Kato-Katz and qPCR, and blood samples were analysed by ELISA. Treatment was administered to all study participants to simulate a mass drug administration campaign. Worms expelled following anthelmintic treatment were collected, measured and sequenced.    

The following have been categorised thus far: household clustering and predisposition to STH infection, and the comparative sensitivity, specificity and variability of Kato-Katz and qPCR. Analysis is on-going on the immunoepidemiological data collected, sequences from expelled Ascaris lumbricoides worms, and the gut microbiomes of infected and uninfected individuals.