Evaluation of Mosquito Blood Meals as a Tool for Wildlife Pathogen Surveillance

Mosquito blood meals provide a biological sample of host blood which can then be used in downstream applications including host-pathogen detection. We conducted DNA barcoding to identify the host species of blood meals from 4557 blood engorged mosquitoes collected in south central Florida, USA. We identified 314 blood meals from invasive wild pigs, 219 wild turkey blood meals, and 1046 white-tailed deer blood meals. From a subset of these host blood meals, we used molecular assays to detect the nucleic acids of Torque teno sus virus 1 (TTSuV1) in wild pig blood meals, Lymphoproliferative virus (LPDV) in wild turkey blood meals, and bluetongue virus (BTV) in white-tailed deer blood meals. None of these wildlife pathogens are transmitted by mosquitoes, but viral nucleic acids circulate in the peripheral blood of host species during or post infection. Prevalence of TTSuV1 in wild pig blood meals was 34%; in wild turkey blood meals the prevalence of LPDV was 2.7%, and BTV prevalence in blood meals of white-tailed deer was 3.6%. These prevalence values were similar to estimates obtained from peripheral blood collected directly from these hosts in Florida. Our analysis suggests that mosquito blood meals are a valuable sampling tool for the detection of wildlife pathogens. We suggest that this type of exogenous xenosurveillance, using mosquitoes to infer information about the vertebrate host, is distinct from endogenous xenosurveillance in which the goal is to understand the role of the arthropod in vectoring a pathogen.