La Crosse virus infection alters blood feeding behavior in Aedes triseriatus and Aedes albopictus (Diptera: Culicidae)

Abstract

The effects of La Crosse virus (LACV) infection on blood feeding behavior in Aedes triseriatus (Say) and Aedes albopictus (Skuse) were investigated in the laboratory by measuring the size of the bloodmeal imbibed and the extent of refeeding by virus-infected and uninfected mosquitoes. LACV-infected Ae. triseriatus and Ae. albopictus took significantly less blood compared with uninfected mosquitoes. Twice as many virus-infected Ae. triseriatus mosquitoes refed compared with uninfected individuals (18 vs. 9%; P < 0.05); however, virus infection had no significant effect on the refeeding rate of Ae. albopictus. Reduction in bloodmeal size followed by an increased avidity for refeeding may lead to enhanced horizontal transmission of the LACV by its principal vector, Ae. triseriatus.

Fig. 1

Cumulative percent of La Crosse virus-infected and uninfected (control) female Aedes albopictus (A) and Aedes triseriatus (B) mosquitoes in relation to size of blood-meal (microliters). Data were fit to a logistic model, Y(x) = 100/(1 + e^−a(x−b)) where a(±95% CL) is a rate constant and b (±95% CL) is the median bloodmeal size. R² for all fitted curves is >0.99. Asterisk indicates a significant difference in the median bloodmeal size, b, between the treatment groups for each mosquito species based on nonoverlapping 84% CIs.