Horse owners, beware. An equine virus is growing more dangerous.

The equine herpes virus type 1, or EHV-1, usually causes a respiratory infection. But the virus also takes a different form that strikes a horse's central nervous system, sometimes causing death.

Wisconsin agriculture officials say researchers have found the neurologic form is growing more prevalent. In 2006, more than 19 percent of EHV-1 cases involved the neurologic strain compared with about 3 percent in the 1960s.

State officials say barn workers and riders should wear boots that can be disinfected and ask visitors to step into a disinfectant wash. Workers also should wash their hands before handling horses and shouldn't share water or feed between horses.

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