Mortality And Reproductive Dynamics of Aedes aegypti (Diptera: Culicidae) Fed Human Blood

Abstract

Mortality is a critical factor in determining a mosquito's ability to transmit pathogens. We investigated the effect of human blood feeding and reproduction on mortality of the dengue virus vector, Aedes aegypti, by conducting a life-table study of male and female mosquitoes maintained on one of three diets: 10% sucrose, human blood or human blood plus 10% sucrose. We examined the effect of host availability by offering human blood to mosquitoes every day or every other day. Mortality of females was age-dependent and best fit by a logistic or logistic-Makeham model. The availability of blood increased survival; survival of females fed blood plus sugar was greater than those only fed sugar. There was a peak in mortality of females fed blood alone early in life that coincided with the initiation of oviposition. When females in the blood alone group were offered blood daily, their mortality was significantly lower than when they were offered blood every other day. Unlike some previous studies, females fed blood plus sugar had higher fitness than females fed blood alone. Increased fitness may have been due to differences in housing mosquitoes individually in separate cages versus as a group of many mosquitoes in each cage. It was not due to longer survival of males who had access to sugar as a food source. Our results demonstrate that reproductively active Ae. aegypti exhibit age-dependent mortality, which refutes the assumption of age-independent mosquito mortality and underscores the need to incorporate age-dependent factors into pathogen transmission models and research on mosquito biology in general.

Parameterization and Sensitivity Analysis of a Complex Simulation Model for Mosquito Population Dynamics, Dengue Transmission, and Their Control

“…A growing number of studies have shown age-dependent mortality in mosquitoes, [28][29][30][31][32] but the form of the relationship between age and mortality and how it changes in space and time in natural systems are not known for most mosquito vector species. Accurate estimates of age-dependent mortality are important, because adult survival determines the probability that a mosquito will live long enough to become infectious and transmit a pathogen during its lifetime.…”

Incubation Periods of Yellow Fever Virus

“…The lowest temperature at which yellow fever infectiousness has been observed to develop in a mosquito is approximately 16.5°C. 21 Although the model predicts that it may occur at lower temperatures, the estimated life span of a mosquito is 30-50 days under ideal conditions, 47 and it is shorter at lower temperatures, 48 making it unlikely for a mosquito to survive a complete incubation period. At higher temperatures, in contrast, the probability of a mosquito surviving the much shorter incubation period is correspondingly greater.…”

Impact of insecticide interventions on the abundance and resistance profile of Aedes aegypti

“…Thus, for the adult life-stage death rates vary by age group. The rate of production of viable eggs per adult is given by b [39].…”