Officials are warning visitors to Zion National Park to stay clear of resident bighorn sheep as a contagious disease moves through the population. The animals are showing symptoms of sore mouth disease, an illness that can be transmitted to humans.
Also known as contagious ecthyma, the disease is common in wild and domestic sheep and goats. It passes from ewes to lambs and symptoms include sores around the mouth and inflamed teats. The sores typically disappear within two to four weeks and the disease is rarely fatal.
There is no cure for the disease in sheep and treatment is not viable due to the number of animals involved, park officials said.
If a human comes in contact with the virus via the saliva or open sores of an infected sheep, they may develop sores on their hands that are painful but usually heal without treatment. So far, no human cases have been reported.
The incubation period for sore mouth disease is one to two weeks, so sick animals may be found throughout the park for many months. If visitors see dead or dying bighorn sheep, they are encouraged to call park dispatch at 435-772-3256.
Although no one knows for sure how many animals live within the park, located 165 miles northeast of Las Vegas in southwestern Utah, an aerial count in 2009 found 114 bighorn sheep outside the park and 115 inside park boundaries.