KJZZ is a service of Rio Salado College,
and Maricopa Community Colleges

Copyright © 2026 KJZZ/Rio Salado College/MCCCD
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

Equine virus closures continue in Tonto National Forest

Salt River wild horse eating eelgrass
Megan Newsham/Cronkite News
A wild horse eats eelgrass from the Salt River northeast of Mesa.

The Tonto National Forest extended its temporary closure of the lower Salt River area to most outside horses and pack animals.

This past week would have been the earliest for a possible quarantine lift, after an equine virus was detected in the wild.

Nearly 300 wild horses roam the lower Salt River. When volunteers first detected the virus, the closure order went out in early December. While not fatal, the Equine Vesicular Stomatitis Virus can cause symptoms like excessive salivation and blister-like lesions in the mouth and other areas.

It can also transmit to humans, though it’s rare and resembles the flu.

“It causes the horses some mild to moderate discomfort obviously because their tongues and their lips are so ulcerated," said state veterinarian Dr. Ryan Wolker. "But virtually all horses that are affected will get over it."

He says the latest case was identified last Friday.

“And typically if we don’t have any detection or identification of newly lesioned animals, newly affected animals, the quarantine will be removed 14 days following that last affected horse," Wolker said.

A total of 17 wild horses have the virus. The next possible quarantine lift could be as early as January, but the closure order says it may last until March.

More Arizona animal news

Jill Ryan joined KJZZ in 2020 as a morning reporter, and she is currently a field correspondent and Morning Edition producer.