D3026: Phenology and pathogen risk presented by tick and tabanid vectors in agriculture

Tick ranges have been expanding throughout the United States over the past decade. Ohio sits on the edge of several expanding ranges and is now home to at least five medically important tick species. These species are capable of transmitting both human and animal pathogens, and tick-borne disease reports have increased in recent years. Data for other agricultural arthropod vectors is lacking or outdated for this region, prompting additional investigation of tabanid biting flies. Bovine anaplasmosis, caused by Anaplasma marginale, is of particular interest due to recent detections in Ohio herds. Dermacentor variabilis (American Dog tick) and tabanid flies are the primary vectors of this disease in the Midwest and may contribute to a multispecies vector community, amplifying its spread. To properly survey the activity of these vector populations, tick dragging at five university-owned agricultural sites resulted in 1,981 collected specimens, including 108 adult and nymphal ticks. Commercial fly traps were also deployed at two of these sites, collecting over 800 adult tabanid flies. Ticks and tabanids were identified to species using light microscopy and approved morphological keys. An attempt was also made to identify tabanid specimens using the CO1 gene. All specimens were tested for known vectored pathogens via rt-PCR. We will discuss vector activity, pathogen prevalence, and disease risk across sites, as well as the implications of multiple vector species on pathogen transmission.