For the Health of It
Mitigation Strategies to Prevent Vesicular Stomatitis Virus Transmission to Equids
Reprinted with permission from Volume 29 , Issue Number 3 of Equine Disease Quarterly
Vesicular stomatitis ( VS ) is a viral disease of horses and other livestock caused by vesicular stomatitis virus ( VSV ), which is endemic in south- ern Mexico and only occasionally moves northward into the United States . The clinical disease is characterized by vesicular ( blister-like ) lesions on the muzzle , lips , tongue , ears , udder , sheath , or coronary bands . While the lesions usually heal on their own , some horses require supportive care . A 2019 outbreak of VSV was the largest in recent history with 1,144 premises affected in eight states ( Colorado , Kansas , Nebraska , New Mexico , Okla- homa , Texas , Utah , and Wyoming ). VS returned this year on April 13 , 2020 , with equine premises in Arizona , New Mexico , and Texas affected . Expansion of the disease to other states is expected this summer . Taking steps now to prevent VSV transmission on equine premises is imperative to limit the spread .
VSV is spread two ways ; natural transmission by insect vectors or direct contact with infected animals . Mitigation strategies targeting insect vectors and implementation of biosecurity to prevent contact with infected animals and contaminated fomites ( shared water troughs , feed buckets , tack , or equipment ) are thought to be the best methods of disease prevention . Known competent insect vectors include black flies ( Simulium spp .), sand flies ( Lutzomyia spp ,), and biting midges ( Culicoides spp .), but other insects may also transmit the disease .
These insect vectors emerge in specific habitats , which helps target implementation of mitigation strategies . Sand flies prefer dry areas , such as tree holes , rock crevices , and animal burrows . Biting midges prefer wet areas , such as wet leaves and mud around ponds or troughs . Black flies prefer flowing water ,
6 • Walking On