Location: Foreign Arthropod Borne Animal Disease Research
Project Number: 3022-32000-062-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2023
End Date: Jul 31, 2026
Objective:
Insect transmitted pathogens pathogens of livestock, such as vesicular stomatitis virus (VSV, Rhabdoviridae: Vesiculovirus) which causes vesicular lesions and Cache valley virus (CVV; Peribunyaviridae: Orthobunyavirus) which cause abortions and congenital abnormalities. VSV is transmitted by biting midges in the genus, Culicoides but may also be transmitted by mosquitoes, and CVV is primarily transmitted by mosquito species, including Aedes albopictus, but may also be transmitted by Culicoides. Over the last several years, there have been recorded outbreaks of CVV among sheep flocks in Arkansas. Impacts of the infection are significant embryo loss among pregnant ewes, fetal abnormalities, and hoof problems, particularly within the Certified Organic flock, which has fewer options for vector control. To address the problem of CVV transmission on this farm and if VSV transmission if it were to be introduced, seasonal vector surveillance will determine which insect species are involved in pathogen transmission of each virus as well as identify the larval habitats. Furthermore, collected Culicoides and mosquitoes for CVV will quantify infection rates of vectors and management methods to prevent or reduce insect transmitted virus transmission will be evaluated. CVV will be examined because it is an endemic virus most similar to Rift Valley Fever virus. Therefore the epidemiological models and mosquito transmission of CVV can be studied to inform possible transmission models of RVF in the US in the event of an outbreak. RVF cannot be studied in the US or in NBAF during the stand up of the facility, therefore endemic viruses will be used until the facility is ready and tested. Furthermore, this is an opportunity to work collaboratively with other units in the United States Department of Agriculture to study the epidemiology of a vector-borne diseases including insect vectors, pathogen, hosts, and environment.
Approach:
1. Determine which species of Culicoides and mosquitoes are present through seasonal vector surveillance.
2. Associate insect abundance and transmission with environmental and weather factors.
3. Identify putative VSV and CVV vector species that may be present by testing collected insects for pathogens using PCR.
4. Recommend appropriate integrated vector management strategies and evaluate them fore efficacy for disease prevention based on surveillance data.
