Community Participation in Habitat Management and Larviciding for the Control of Malaria Vectors in Southern Malawi

Larval source management (LSM) could reduce malaria transmission when executed alongside core vector control strategies. Involving communities in LSM could increase intervention coverage, reduce operational costs, and promote sustainability via community buy-in. We assessed the effectiveness of community-led LSM to reduce anophe-line larval densities in 26 villages along the perimeter of Majete Wildlife Reserve in southern Malawi. The communities formed LSM committees which coordinated LSM activities in their villages following specialized training. Effectiveness of larviciding by LSM committees was assessed via pre-and post-spray larval sampling. The effect of community-led LSM on anopheline larval densities in intervention villages was assessed via comparisons with densities in non-LSM villages over a period of 14 months. Surveys involving 502 respondents were undertaken in intervention villages to explore com-munity motivation and participation, and factors influencing these outcomes. Larviciding by LSM committees reduced anopheline larval densities in post-spray sampling compared with pre-spray sampling (P , 0.0001). No differences were observed between anopheline larval densities during pre-spray sampling in LSM villages and those in non-LSM villages (P 5 0.282). Knowledge about vector biology and control, and someone's role in LSM motivated community participation in the vector control program. Despite reducing anopheline larval densities in LSM villages, the impact of the community-led LSM could not be detected in our study setting because of low mosquito densities after scale-up of core malaria control interventions. Still, the contributions of the intervention in increasing a community's knowledge of malaria, its risk factors, and its control methods highlight potential benefits of the approach.

Automated summary

Larval source management (LSM) is an effective strategy to reduce malaria transmission, and involving communities in LSM can increase intervention coverage and promote sustainability. In this study, community-led LSM activities were carried out in 26 villages in Malawi, resulting in a reduction in anopheline larval densities. However, the impact of community-led LSM could not be detected due to low mosquito densities after the scale-up of core malaria control interventions. The study highlights the potential benefits of increasing community knowledge about malaria and its control methods.