The yellow fever mosquito Aedes aegypti Linnaeus is a major vector of several viruses that cause disease in humans and other animals. Conventional insecticides have been used for vector control, but can be problematic because Ae. aegypti and other mosquitoes can evolve resistance to them and they can negatively impact non‐target insect species. Therefore, there is a strong demand for novel methods in Ae. aegpyti vector control strategies. Our study investigated whether the sugar alcohol, erythritol, has potential as a novel insecticide for mosquito control. Erythritol is lethal to several dipteran species yet has been deemed safe for consumption by humans and other mammals. We tested the impact of erythritol on Ae. aegypti by comparing the longevity of larvae reared in erythritol‐treated water and adult females maintained on erythritol. We also tested whether sucrose supplementation impacts the effects of erythritol on adult longevity. For larvae, erythritol exposure at concentrations as low as 0.1 m is lethal, with LC50 at 48 hr of 0.11 m for early stage (3‐day old) larvae and 0.42 m for late stage (5‐day old) larvae. For adult females, maintenance on erythritol is lethal at concentrations as low as 0.5 m, with LC50 at 72 hr of 1.60 m. Further, a mixture of 1 m sucrose/1 m erythritol solution is more lethal to adult females than 1 m erythritol solution alone, suggesting that erythritol in combination with sucrose could comprise a toxic sugar bait. These results provide promising evidence for erythritol as a novel larvicide and adulticide for Ae. aegypti.

Mosquito-borne pathogens have spread throughout tropical regions of the Western Hemisphere causing increased burden of disease in the region. Outbreaks of dengue fever, yellow fever, chikungunya, West Nile, and Zika have occurred over the past several years. Mosquito blood-feeding patterns need to be assayed to assist in determining which vertebrates could act as hosts of these mosquito-borne pathogens and which mosquito species could act as vectors. We conducted bloodmeal analyses of mosquitoes collected at Lomas Barbudal Biological Reserve, a dry tropical forest reserve in Costa Rica. Mosquitoes were collected using backpack aspirators and light, gravid, and resting traps, and then identified morphologically. Blood-fed mosquitoes underwent DNA extraction, PCR amplification, and sequencing of the vertebrate cytochrome b and cytochrome c oxidase 1 genes to identify vertebrate bloodmeal hosts. Several mosquitoes known to vector pathogens were found including Culex (Melanoconion) erraticus Dyar & Knab (Diptera: Culicidae), Cx. (Mel.) pedroi Sirivanakarn & Belkin, Aedes (Stegomyia) albopictus Skuse, Ae. (Ochlerotatus) scapularis Rondani, Ae. (Och.) serratus Theobald, and Ae. (Och.) taeniorhynchus Wiedemann. The most common bloodmeal hosts were basilisk lizards (Basiliscus vittatus) Wiegmann (Squamata: Corytophanidae) in Culex (Linnaeus) species and white-tailed deer (Odocoileus virginianus) Zimmermann (Artiodactyla: Cervidae) in Aedes (Meigen) species. These results show the diversity of mosquito species in a tropical dry deciduous forest and identify associations between mosquito vectors and potential pathogen reservoir hosts. Our study highlights the importance of understanding interactions between vector species and their hosts that could serve as predictors for the potential emergence or resurgence of mosquito-borne pathogens in Costa Rica.