The Leucosphyrus Group and Its Role in Malaria Transmission in Thailand: A Review

Abstract

Malaria is one of the most important vector-borne diseases transmitted by Anopheles mosquitoes. A total of 81 Anopheles species have been reported in Thailand, of which seven are confirmed human malaria vectors. Among these vector species, Anopheles baimaii Sallum & Peyton and Anopheles dirus Peyton & Harrison, which belong to the Leucosphyrus Group, play key roles in outdoor transmission due to their association with forested areas, making them particularly difficult to control. Understanding the biology and ecology of these species and other species within the Leucosphyrus Groups is critical because their high vector competence and specialized behaviors sustain residual transmission in “pocket foci” and facilitate the spillover of nonhuman primate malaria, which poses a major challenge to national elimination goals. Hence, traditional indoor–based interventions cannot effectively control these exophagic vectors and underscore the necessity of an integrated One Health approach incorporating public health, wildlife management, and environmental conservation to effectively manage zoonotic risks and sustain malaria elimination in Thailand and surrounding countries.