The Effect of a Water, Sanitation, and Hygiene Intervention on Clinical Trachoma: A Cluster-Randomised Trial

Few randomised trials have been done to assess the impact of hygiene interventions on trachoma even though hygiene improvements feature prominently in the strategy for global elimination of trachoma. This study's aim was to determine if implementing an integrated water, sanitation, and hygiene (WASH) intervention in a hyperendemic region of Ethiopia would reduce clinical signs of trachoma.

In a parallel-group cluster-randomised trial, 40 Ethiopian communities were randomised in a 1:1 ratio to a WASH intervention or to delayed intervention (i.e., control) (ClinicalTrials.gov NCT02754583). No antibiotic mass drug administration was undertaken. Annual monitoring visits included photography of the superior tarsal conjunctiva. Clinical trachoma-a pre-specified secondary outcome-was assessed from photographs presented in a random order to masked photo-graders.

At baseline, conjunctival photographs were taken on 1131 children aged 0-9 years in the WASH arm and 1229 children in the control arm. The mean number of follicles at baseline was 3.8 (95% CI: 3.1, 4.6) in the WASH arm and 3.7 (95% CI: 2.9, 4.4) in the control arm, which increased to a mean of 5.9 (95% CI: 5.1-6.6) in the WASH arm and 5.4 (95% CI: 4.6-6.1) in the control arm after 3 years (0.5 higher in the WASH arm, 95% CI: -0.6 to 1.5, p = 0.66). The mean papillary score increased from 3.3 (95% CI: 3.1-3.5) to 3.7 (95% CI: 3.5-3.9) in the WASH arm and from 3.2 (95% CI: 3.0-3.4) to 3.5 (95% CI: 3.3-3.7) in the control arm (month 36 values 0.2 greater in the WASH arm, 95% CI: -0.1 to 0.4; p = 0.49). No adverse events were reported in either treatment arm.

An integrated WASH intervention delivered in the absence of mass antibiotic distributions did not reduce clinical trachoma outcomes in an area with hyperendemic trachoma.