Beat the heat:Culex quinquefasciatusregulates its body temperature during blood-feeding

Abstract

<jats:title>Abstract</jats:title><jats:p>Mosquitoes are regarded as one of the most dangerous animals on earth. As they are responsible for the spread of a wide range of both human and animal diseases, research of the underlying mechanisms of their feeding behavior and physiology is critical. Among disease vector mosquitoes, <jats:italic>Culex quinquefasciatus</jats:italic>, which is a known carrier of West Nile virus and Western Equine Encephalitis, remains relatively understudied. As blood sucking insects, adaptations (either at the molecular or physiological level) while feeding on warm blood is crucial to their survival, as overheating can result in death due to heat stress. Our research aims to study how <jats:italic>Cx. quinquefasciatus</jats:italic> copes with heat associated with the ingestion of a warm blood-meal and to possibly uncover the adaptations this species uses to avoid thermal stress. Through the use of thermographic imaging, we analyzed the body temperature of <jats:italic>Cx. quinquefasciatus</jats:italic> while blood feeding. Infrared thermography has allowed us to identify a cooling strategy, evaporative cooling via the production of fluid droplets, and an overall low body temperature in comparison to the blood temperature during feeding. Understanding <jats:italic>Cx. quinquefasciatus’</jats:italic> adaptations and various strategies that they employ to reduce their body temperature while blood-feeding constitutes the first step towards the discovery of potential targets of opportunity for their control.</jats:p><jats:sec><jats:title>Highlights</jats:title><jats:list list-type="bullet"><jats:list-item><jats:p>Mosquitoes have evolved to cope with heat stress associated with warm blood ingestion</jats:p></jats:list-item><jats:list-item><jats:p><jats:italic>Culex quinquefasciatus</jats:italic> displays heterothermy while blood-feeding</jats:p></jats:list-item><jats:list-item><jats:p>The abdominal temperature decreases due to evaporative cooling using urine droplets</jats:p></jats:list-item><jats:list-item><jats:p>Overall, the mosquito body temperature is much cooler than the ingested blood</jats:p></jats:list-item></jats:list></jats:sec>