Survival of starved Aedes aegypti (Diptera : Culicidae) in Puerto Rico andThailand

Survival of adult Aedes aegypti (L.) was studied in Thailand (1995) and Pue rto Rico (1996) during periods of high and low dengue virus transmission. R esting males and females were collected inside houses by aspiration. Female s were separated into different cages by their degree of engorgement and ov arian development. Teneral adults were obtained from pupae collected from n atural breeding sites. All mosquitoes were given access to water, held at a mbient temperature in the shade, and their survival monitored daily. We cal culated median survival for each stage to estimate when mosquitoes had to f eed again or die. No differences in survival between seasons were observed in Thailand. In Puerto Rico, except for wild males, survival was longer in the cool/dry season than in the hot/rainy season, indicating that mosquitoe s may need to feed more frequently during the high than low dengue transmis sion season. During both study periods and at both sites, blood-engorged fe males survived as long or longer than mosquitoes in other gonotrophic or de velopmental stages. Except in Puerto Rico during the cool season, when fema les had a relatively high probability of surviving 3-4 d without feeding, f emales needed to feed approximately every other day to avoid death caused b y starvation. Our results indicate that in some regions, there are seasonal differences in the length of time female Ae. aegypti can survive without f eeding, females with a blood meal can survive for a longer time than those without blood, and teneral males can live longer without food than teneral females.