Location: Arthropod-borne Animal Diseases Research
Project Number: 3020-32000-020-007-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jun 1, 2023
End Date: May 31, 2025
Objective:
Bluetongue virus (BTV) has a segmented genome, which is capable of reassortment when two serotypes of BTV infect the same cell. Reassortment can occur in either the livestock host and the midge vector, and ultimately lead to the emergence of a new serotype. BTV causes a persistent, life-long infection in the midge. In areas where multiple serotypes of BTV are present, midges could become infected with more than one serotype of BTV simultaneously or during subsequent bloodmeals. The aim of this research is to study the impacts of timing of two BTV serotype acquisition on virus infection of the midge’s body, dissemination to the head/salivary glands, and transmission.
Approach:
Midges will be infected two distinct serotypes of bluetongue virus (BTV) in two phases: I) midges will be fed infectious bloodmeals with two serotypes of BTV simultaneously, and II) midges will be co-infected with two staggered infectious bloodmeals. For both phases, most of the midges will be dissected to remove the heads from the bodies and assayed for infectious virus. The remaining midges will be fed on the embryonated chicken egg (ECE) model to measure viral transmission. Reassortment will be evaluated via whole genome sequencing for the viruses in the midge heads and bodies, and recovered from the ECEs.
