Social and behavioural considerations for responding to Anopheles stephensi in Africa: a scoping review

Anopheles stephensi has been identified in multiple African countries over the past decade. Unlike malaria vectors endemic to Africa, invasive An. stephensi shares characteristics with Aedes aegypti, including laying eggs in artificial containers near human dwellings, particularly in urban areas. These characteristics pose a threat to malaria control and elimination and shape needed interventions, including the role of individuals, households, and communities. Due to the urgency to develop strategies for the African context, this scoping review sought to identify social and behaviour change (SBC) considerations for responding to An. stephensi in Africa, by synthesizing information currently available, leveraging lessons from Anopheles and Aedes control, to inform evidence-based guidance.

The review included core interventions promoted for malaria (insecticide-treated nets, indoor residual spraying, and care-seeking for fever) and larval source management (LSM) interventions. A systematic search of four online databases (PubMed; EMBASE; Global Health; and Global index medicus) used intervention-specific terms defined a priori. Peer-reviewed articles published from 2000 to 2021, with a description of individual, household, or community behaviour and/or participation in one or more core or LSM interventions were included. For LSM interventions, included articles related to control of malaria and Aedes-borne infections.

Of 3,306 articles screened, 42 met inclusion criteria. Twenty-seven were malaria control studies with two on An. stephensi. Fourteen publications targeted Ae. aegypti and one did not specify vectors. In low transmission contexts, malaria-related prevention behaviours tend to be practiced at lower rates, underscoring the need to address the factors driving these behaviours and effectively tailor SBC to the needs of higher risk groups. It is also critical to create early and meaningful partnerships with affected communities. Finally, highly specific guidance for governments, communities, and households is paramount, particularly for LSM interventions, as missing any specific step in the necessary behaviours for these interventions will reduce their potential effectiveness.

The dearth of An. stephensi-specific articles underscores the need for further research and documentation as countries respond to the threat. This review highlights the importance of tailoring SBC to groups experiencing higher risk, like those moving between higher and lower transmission areas or working in construction sites. Learnings from Aedes control provides valuable insights into LSM for An. stephensi and opportunities for integrated approaches to SBC, including multi-sectoral collaboration, partnership with community leaders and civil society.