Genetic Dynamics and Dispersion Pattern Changes in Aedes aegypti Populations (Diptera: Culicidae) in Yunnan Province, China, over Three Consecutive Years

Aedes aegypti is the primary vector of mosquito-borne viruses and threatens human health globally. To monitor temporal changes in the population genetics of Ae. aegypti in Yunnan Province, we collected specimens from five sites between 2016 and 2018 and analyzed them at nine microsatellite loci and the mitochondrial cox I gene. Genetic diversity in these populations rose initially and then declined over the study period. The inbreeding coefficient shifted from a heterozygous state toward moderate inbreeding. Ten cox I haplotypes were identified, with haplotypes H06 and H09 prevalent across regions, while other haplotypes were limited to specific regions or years. Clustering analyses demonstrated significant population shifts of Ae. aegypti across the five sampling sites from 2016 to 2018. AMOVA analysis of all Ae. aegypti populations indicated that from 2016 to 2018, the main source of variation was predominantly among individuals, accounting for 76.43%, 65.15%, and 80.36%, respectively. Population dispersion patterns across locations initially increased and then decreased over time. Therefore, continuous monitoring is essential, and particular attention should be paid to intra-provincial spread, especially between port and urban areas.