Indigenous knowledge and plant species used as mosquito repellents in the West Nile Subregion, Uganda.

BACKGROUND: Female Anopheles mosquitoes are the primary vectors for malaria transmission within communities, significantly contributing to the high burden of malaria in Africa overall and Uganda specifically. Many tropical plants have insect-repellent properties and have traditionally been used in their native regions to prevent mosquito bites. METHODS: A cross-sectional ethnobotanical survey was conducted between January 2025 and May 2025 in five districts of the West Nile Subregion: Adjumani, Moyo, Madi-Okollo, Pakwach, and Obongi. Semi-structured questionnaires were used to collect data on indigenous knowledge about mosquito repellents from 57 respondents, who were selected through purposive and snowball sampling techniques. The ethnobotanical data were analyzed using descriptive statistics, the informant consensus factor, and preference ranking. RESULTS: A total of 42 plant species from 40 genera and 25 families were documented as being used to repel mosquitoes. The plants most commonly used for this purpose were: Azadirachta indica A.Juss. (9), Boswellia papyrifera (Caill.) (7), Aeschynomene americana L. (6), Mesosphaerum suaveolens (L.) Kuntze. (6), and Ocimum gratissimum L. (5). The most common indigenous method for repelling mosquitoes involves burning either dry cow dung (32%) or dry goat droppings (20%). Most of the plant species belong to the families Fabaceae (10), Lamiaceae (4), and Asteraceae (3). The majority of the plant species used were trees (43%) and herbs (42%), with leaves (42%) and seeds (12%) being the most frequently used plant parts. Except for Cymbopogon citratus (DC.) Stapf and M. suaveolens, which are used as live plants for repelling mosquitoes, all other plant species used were prepared by burning or smoking indoors. CONCLUSIONS: Communities in the West Nile Subregion, especially those living along the River Nile, possess rich indigenous knowledge and practices used to repel mosquitoes in their efforts to control deadly malaria.