DENVER (AP) – Colorado agriculture officials say a viral disease that can cause fever, loss of appetite, and lesions of the mouth in animals has been diagnosed in at least three yaks.

State agriculture officials said Tuesday that epizootic hemorraghic disease was diagnosed in yaks at two locations in Larimer County and one location in Alamosa County.

The virus doesn’t affect people. It is spread by insects including midges or gnats.

State veterinarian Keith Roehr says a hard frost will kill the virus and insects that carry it. He says ranchers can use insect control to protect their animals until then.

The agriculture department says investigators are trying to determine whether the Colorado cases are tied to cases in Nebraska, where a number of deer have been infected.

(© Copyright 2012 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)