Molecular and Behavioral Characterization of Anopheline Species in Indonesia and the Western Kenyan Highlands

Malaria is a mosquito-borne parasitic disease that poses a significant public health threat to millions of people worldwide. Malaria is transmitted by female Anopheles mosquitoes. Mosquitoes in the genus Anopheles are incredibly diverse, with different ecologies and behaviors that impact how effectively they can act as vectors of malaria parasites. In areas where there are several different anopheline species, this diversity can sustain malaria transmission through seasons and intensive malaria control interventions.

Part of this work addresses the limits of the utility of morphological and molecular species identification in areas of high biological diversity, such as in Indonesia. In areas with many closely related species, which may belong to the same species group or cryptic species complex, molecular tools are essential for the accurate identification of vector species. In areas with more distantly related species that can be discriminated using morphological keys, molecular species identification may not be necessary. Site-specific evaluation of species compositions at the molecular level is recommended prior to the implementation of any control or monitoring program.

Species-specific behaviors ultimately determine the effectiveness of traps and mosquito-based control interventions in any area. In three different sites in Indonesia, different traps were found to be effective for collecting anophelines, based on the particular biology of those species. A detailed study of host feeding behavior demonstrated that even a set of zoophilic, outdoor biting anophelines can contribute to malaria transmission. Animal-based control methods may be useful for vector control or monitoring in this area. In Sub-Saharan Africa, there are regions with uncharacterized anopheline species which demonstrate behaviors that enable them to avoid typical mosquito-targeted malaria control interventions. This work has identified potential novel malaria vectors in the Western Kenyan Highlands. The accurate characterization of these species and their associated behaviors is crucial for effective malaria control and elimination.

Overall, this work demonstrates that anopheline species diversity and behavior have important implications for malaria control. The ultimate goal of this work is to inform mosquito-targeted malaria control efforts in order to effectively reduce malaria transmission. These results will contribute to our understanding of the distribution of vector species, their behavioral patterns, and population structure, as well as provide new diagnostic tools.