Age and gender trends in insecticide-treated net use in sub-Saharan Africa: a multi-country analysis

Africa carries a disproportionately higher share of the global malaria burden, with 90% of cases and deaths occurring on the continent. The World Health Organization recommends the use of insecticide-treated nets as a key element of vector control, and distribution of free ITNs is a core intervention in national malaria control strategies of all sub-Saharan Africa countries. Recent studies have shown that ITN use is higher among females compared to males, and is correlated with age, with higher use in certain age groups such as infants and children under 5 years of age. The association of age with ITN use is also moderated by gender, with men, older children, and teenagers less likely to sleep under an ITN compared to women and children under 5 years old. It is unclear whether certain household members are prioritized only because the number of nets in the household is not enough. This study explores the role of household ITN supply in the variation in ITN use among household members in sub-Saharan Africa. Data from recent national surveys in 29 malaria-endemic countries were included in the analysis. The main outcome of the study is use of an ITN the previous night, and the main predictor variables of interest include household ITN supply, gender, and age of de facto household members. Household ITN supply was defined as the number of ITNs present in the household divided by the de jure household members, and was further dichotomized into 'not enough' (ITN: person ratio of less than 0.5) versus 'enough' (ITN: person ratio of 0.5 or more). The study found that having enough ITNs in the household increases the level of use and decreases existing disparities between age and gender groups. ITN distribution via mass campaigns and continuous distribution channels should be enhanced as needed to ensure that households have enough ITNs for all members, including men and school-aged children.