부산대학교 도서관

Aedes aegypti is a highly efficient vector for numerous pathogenic arboviruses including dengue virus (DENV), Zika virus, and yellow fever virus. This efficiency can in part be attributed to their frequent feeding behavior. We previously found that acquisition of a second, full, non-infectious blood meal could accelerate virus dissemination within the mosquito by temporarily compromising midgut basal lamina integrity; however, in the wild, mosquitoes are often interrupted during feeding and only acquire partial or minimal blood meals. To explore the impact of this feeding behavior further, we examined the effects of partial blood feeding on DENV dissemination rates and midgut basal lamina damage in Ae. aegypti. DENV-infected mosquitoes given a secondary partial blood meal had intermediate rates of dissemination and midgut basal lamina damage compared to single-fed and fully double-fed counterparts. Subsequently, we evaluated if basal lamina damage accumulated across feeding episodes. Interestingly, within 24 hours of feeding, damage was proportional to the number of blood meals imbibed; however, this additive effect returned to baseline levels by 96 hours. These data reveal that midgut basal lamina damage and rates of dissemination are proportional to feeding frequency and size, and further demonstrate the impact that mosquito feeding behavior has on vector competence and arbovirus epidemiology. This work has strong implications for our understanding of virus transmission in the field and will be useful when designing laboratory experiments and creating more accurate models of virus spread and maintenance. Author summary: Aedes aegypti is an important vector of many arboviruses that profoundly affect human health. Despite its importance as a vector, the impact of field-realistic Ae. aegypti feeding behavior on virus transmission is poorly understood. In this study, we investigated the physiological impacts of blood meal size and number on vector competence. We found that partial blood meals—common when mosquitoes feed on defensive hosts—are sufficient to increase mosquito midgut basal lamina damage and dengue virus dissemination. Nevertheless, virus dissemination still occurred in the absence of heightened midgut damage, suggesting that mosquito midguts are not impermeable to virus escape. We also observed that frequent successive blood feeding results in slightly higher levels of midgut damage with each instance of feeding. These experiments more closely mimic mosquito feeding behavior in field settings and suggest that current studies often underestimate the impact of mosquito feeding behavior on virus dissemination and transmission dynamics. [ABSTRACT FROM AUTHOR]