Field Survey of Anopheles Mosquito and Their Culturable Gut Bacteria in the Border Regions of Yunnan Province, China

Despite the elimination of domestic malaria transmission within China, the border areas of Yunnan Province continue to face a heightened risk of imported cases due to the presence of diverse Anopheles mosquito species and the widespread burden of malaria in neighboring countries. While the mosquito gut microbiota offers a promising avenue for developing anti-malaria strategies, a meticulous investigation of the various Anopheles species and their associated gut microbiota in Yunnans border areas has yet to be undertaken. To address this gap, field surveys were conducted over the years 2020, 2021, and 2023. These surveys resulted in the collection of a substantial sample comprising 4,221 adult female mosquitoes spanning sixteen species with Anopheles sinensis identified as the predominant species. Furthermore, 741 cultivable strains of gut symbiotic bacteria were isolated and classified into four phyla comprising 109 genera with the composition of dominant bacteria varying annually. This study provides valuable insights into the population dynamics of malaria vectors in the border regions of Yunnan province, China, along with the intestinal bacteria they harbor including several bacterial species which exhibit promising anti-plasmodium effects. By leveraging the antagonistic effects of symbiotic bacteria against Plasmodium, our findings contribute to an ongoing global endeavor to develop innovative Anopheles management and malaria prevention strategies.