Understanding men's participation in mass drug administration: evidence from a cluster-randomised trial of community-based deworming in Malawi

Background: Mass drug administration (MDA) is a key strategy in the response to neglected tropical diseases (NTDs). Operational research indicates that coverage of adult men in MDA is frequently lower as compared to adult women, but this remains poorly understood and obscured by a lack of routine sex-disaggregated reporting. Such differences may represent a potential threat to NTD strategies that require high MDA treatment coverage to achieve control or elimination objectives. Methods: Using detailed treatment data from a cluster-randomised trial of community-based MDA for soil-transmitted helminths (STH) conducted in southern Malawi, this secondary analysis describes sex-specific trends in coverage over six consecutive rounds of MDA delivered biannually at household level. We report community-level coverage by both a per-protocol (trial) definition, and pragmatic operational definition to simulate routine implementation. We used multilevel mixed-effects logistic regression to investigate individual, household and programme factors associated with non-treatment by both coverage definitions amongst adult men. Results: Adult mens participation in MDA was substantially and consistently lower than adult womens. Median difference (female minus male) in community-level protocol coverage was 14.9% (IQR: 9.2, 19.6), increasing to 21.7% (IQR: 15.9, 28.7) by operational coverage. Factors associated with increased odds of non-treatment were similar by coverage definition and included younger age, lower levels of education, and previous reported absenteeism; and were reduced by modifiable programmatic factors such as the day or time of household visit. Conclusions: This analysis highlights the persistence of inequity for adult men in participation in MDA, despite a well-resourced context that achieved high coverage of adult women. More nuanced MDA strategies that respond to the needs of adult men will be required to achieve equitable coverage, accompanied by robust monitoring and evaluation to evaluate their effectiveness at reaching this under-served population.