# Spatial Distribution and Biodiversity of Anopheles Mosquito Species Across Climatic Zones in Burkina Faso: Implications for Malaria Vector Control

## TL;DR

This study maps the distribution of malaria-carrying Anopheles mosquitoes in Burkina Faso, showing how species vary by region and climate.

## Contribution

The study provides a detailed spatial and ecological analysis of Anopheles biodiversity in Burkina Faso to inform localized malaria control.

## Key findings

- An. gambiae s.l. was the most abundant species, with highest numbers in the Sudano-Sahelian zone.
- Biodiversity of Anopheles species decreased from southern to northern Burkina Faso.
- An. coluzzii dominated in the Sahelian and Sudano-Sahelian zones, while An. gambiae s.s. was more common in the Soudanian zone.

## Abstract

Malaria transmission in sub-Saharan Africa is dominated by the An. gambiae complex and An. funestus group, whose distribution varies across ecological settings. Secondary species occur at lower densities, but their role in transmission may differ from one locality to another depending on local conditions. Assessing Anopheles biodiversity using ecological indices is therefore essential to characterise their diversity and relative abundance. This study investigated the biodiversity and spatial distribution of Anopheles species across the three climatic zones of Burkina Faso to guide effective vector control strategies. Indoor resting mosquitoes were collected from 67 health districts across the 13 regions of Burkina Faso between September and December 2022 using pyrethroid spray catches. A total of 30,521 Anopheles mosquitoes were identified, with An. gambiae s.l. dominating (94.4%). The Sudano-Sahelian zone recorded the highest abundance, followed by the Soudanian and Sahelian zones. Biodiversity decreased from humid southern to arid northern areas, with the Soudanian zone showing the highest diversity. Molecular analysis of 2026 An. gambiae s.l. specimens revealed marked heterogeneity: An. coluzzii predominated in Sahelian (74.9%) and Sudano-Sahelian (71.2%) zones, while An. gambiae s.s. was most frequent in the Soudanian zone (53.8%). These results highlight spatial and ecological differences in Anopheles composition across Burkina Faso and emphasize the need for locally adapted malaria vector control strategies.