Effects of temperature on biting persistence of Aedes aegypti (Diptera: Culicidae)

Host-vector contact is central to mosquito-borne disease transmission, during which pathogens are transmitted via saliva injection or blood feeding. Biting persistence, defined as the number of repeated biting attempt when interrupted, is an understudied trait that may influence transmission risk. Currently it is unknown how temperature may influence biting persistence. We tested the effect of ambient temperature on biting persistence in Aedes aegypti (Linnaeus), under controlled laboratory conditions. Individual mosquitoes (n = 141) were assayed at four temperatures (18, 23, 28, and 33 °C). Biting persistence was measured as the number of landings over a 1-h period on the experimenter's arm when probing was repeatedly prevented. Results showed that persistence differed significantly across temperature treatments, peaking at 28 °C and declining at 18 and 33 °C. Temporal analysis showed that biting persistence declined steadily during the 1-h assay period. To control for experimental variations in relative humidity, mosquito age, wing size, assay time, starvation period, and acclimation period, multivariate models were fitted with temperature included as both linear and quadratic terms. Model comparisons and other robustness tests supported that temperature significantly affected biting persistence; and suggested a thermal optimum at intermediate conditions. While this study focused specifically on temperature effects, in natural settings other factors such as host defensive behaviors, mosquito learning and memory, and additional environmental variables such as humidity may also shape biting persistence. Because pathogen transmission can occur even during interrupted feeding attempts, biting persistence may contribute to increased transmission risk, likely near thermal optima.