Evaluating impacts of improved flooring on enteric and parasitic infections in rural households in Kenya: study protocol for a cluster-randomised controlled trial

Introduction: Earthen floors are often damp or dusty and difficult to clean, providing an ideal environment for faecal pathogens and parasites. Observational studies have revealed associations between household flooring and health outcomes, but robust experimental evidence is scant. This study will evaluate the impact of an improved household flooring intervention on enteric infections, soil-transmitted helminth (STH) infections and tungiasis through implementation of a cluster-randomised trial in two rural settings in Kwale and Bungoma Counties, Kenya. Methods and analyses: 440 clusters (households) across both sites are allocated to control or intervention group, in which a low-cost, sealed, washable, cement-based floor is installed in eligible buildings of the dwelling, alongside a floor-care guide provided during an induction meeting. Following baseline assessments in both groups, all individuals over 1 year receive albendazole and those infected with tungiasis receive benzyl benzoate. Primary outcomes are as follows: prevalence of enteric infections in children under 5 years assessed via stool surveys and PCR; prevalence of tungiasis infection in children 1–14 years based on clinical exam; and prevalence of STH infection in all household members over 1 year assessed via Kato-Katz. Secondary outcomes include the following: intensity of STH and tungiasis infections; prevalence of caregiver-reported gastrointestinal illness in children under 5; quality of life and well-being measures; and environmental contamination. A process evaluation investigates intervention acceptability, durability, practicality and cost. Ethics and dissemination: The protocol has been approved by ethics committees of The Kenya Medical Research Institute, The Kenya National Commission for Science Technology and Innovation, and The London School of Hygiene & Tropical Medicine. Following the 12-month implementation period and final assessments, control households are offered improved floors. Results will be disseminated within Kenya, to the Ministries of Health and of Lands, Public Works, Housing and Urban Development, and to subnational leadership and communities. Dissemination will also occur through publications and conference presentations. Trial registration number: NCT05914363.