Meeting Abstract
In vector-borne parasite systems, transmission dynamics depend on interactions within and between hosts and vectors. For example, host behavior and physiology mediate exposure to vectors and susceptibility to parasites. Host traits also impact vector-feeding preferences and thus ultimately influence which individuals contribute to the spread of infections. However, we still know very little about the consequences of vector preferences on vector-specific traits. Variation in blood meal quality and quantity could impact both reproductive success and survival of female mosquitoes and their progeny. Disproportionate feeding on certain hosts could thus influence transmission dynamics directly (through the propensity of adult mosquitoes to survive to bite subsequent hosts post-reproduction) and indirectly (through the quantity and quality of offspring produced). We have previously shown that glucocorticoid stress hormones mediate variation in vector choice of avian hosts. When given a choice of control and corticosterone-manipulated zebra finches, a cosmopolitan vector (the southern house mosquito, Culex quinquefasciatus) consistently preferred to feed on birds with elevated stress hormone levels. Here, we examined the consequences to mosquitoes of feeding on hormone-manipulated zebra finches. Mosquitoes that fed on birds with experimentally elevated corticosterone levels laid eggs more rapidly but also experienced greater total mortality over a 30-day trial compared to mosquitoes that fed on implant-control birds. Our findings suggest that vector preferences may have important consequences for short-term and long-term epidemiological and ecological dynamics including pathogen spread and persistence, vector density, and the spatiotemporal distribution of vectors and parasites, especially in anthropogenically-modified habitats where stressors are often more common.
