Developing low-cost house floors to control tungiasis in Kenya - a feasibility study

Abstract

Context: Tungiasis is a neglected tropical skin disease endemic in resource-poor communities. It is caused by the penetration of the female sand flea, Tunga penetrans, into the skin causing immense pain, itching, difficulty walking, sleeping and concentrating on school or work. Infection is associated with living in a house with unsealed earthen house floors.

Methods: This feasibility study used a community-based co-creation approach to develop and test simple, locally appropriate, and affordable flooring solutions to create a sealed, washable floor for the prevention of tungiasis. Locally used techniques were explored and compared in small slab trials. The floor with best strength and lowest cost was pilot trialed in 12 households with tungiasis cases to assess its durability and costs, feasibility of installation in existing local houses using local masons and explore community perceptions. Disease outcomes were measured to estimate potential impact.

Results: It was feasible to build the capacity of a community-based organization to conduct research, develop a low-cost floor and conduct a pilot trial. The optimal low-cost floor was stabilized local subsoil with cement at a 1:9 ratio, installed as a 5 cm depth slab. A sealed floor was associated with a lower mean infection intensity among infected children than in control households (aIRR 0.53, 95%CI 0.29-0.97) when adjusted for covariates. The cost of the new floor was US$3/m² compared to $10 for a concrete floor. Beneficiaries reported the floor made their lives much easier, enabled them to keep clean and children to do their schoolwork and eat while sitting on the floor. Challenges encountered indicate future studies would need intensive mentoring of masons to ensure the floor is properly installed and households supervised to ensure the floor is properly cured.

Conclusion: This study provided promising evidence that retrofitting simple cement-stabilised soil floors with locally available materials is a feasible option for tungiasis control and can be implemented through training of community-based organisations. Disease outcome data is promising and suggests that a definitive trial is warranted. Data generated will inform the design of a fully powered randomized trial combined with behaviour change communications.

Trial registration: ISRCTN 62801024 (retrospective 07.07.2023).

Keywords: Floors; Housing; NTD; Prevention; Tunga penetrans; Tungiasis.

Fig. 1

Typical rural mud and brick houses with their unsealed earthen floors in the study area in coastal Kenya

Fig. 2

Installation of the low-cost floor. A) Excavating the existing surface, B) Compacting the soil, C) Adding cement to local subsoil (1 part cement with 9 parts soil), D) Mixing cement with sub-soil, E) Adding water to the mix, F) Cement-stabilized soil laid on top of the compacted soil, G) Compacting the cement-stabilized soil, H) Spreading the “nill” finish (cement/water slurry), I) The completed floor

Fig. 3

Study Flow Chart. HH = household, ptps = participants, infected children enrolled at baseline