SALT LAKE CITY (AP) - A state veterinarian predicts Utah "will be out of the woods" in 30 days after a virus affected hundreds of horses and caused quarantines this summer.

Earl Rogers said the state has lifted quarantines on all but four horse operations.

"We haven't seen any symptoms in 14 days," said Steve Allred, owner of Vista Farms in West Jordan, where 73 horses were infected. He expects his restrictions to be lifted this week.

The virus rarely kills adult horses, but experts say it threatens breeding stables. It causes horses to abort their foals and is spread through a stallion's semen.

The virus appeared in Utah after an infected stallion in New Mexico was used to breed animals in 18 states.

State officials have not discouraged horse owners from attending competitions but have advised them to keep sick animals at home. The virus can spread through respiratory contact as well as sexual activity.

The Utah Paint Horse Club show was held over the weekend in Salt Lake County, the sixth-largest such show in the country.

Show secretary Marla Fadel said organizers got several calls about the virus. Attendance was down to 239 horses from 257 last year, but Fadel knew only two cancellations that were tied to the virus.

"If we worried about every disease that came around, we wouldn't go to any horse shows," said Judy Ford, a Las Vegas horse owner.

D & M Paint Horses and Stables in Salt Lake City was quarantined last month, but tests for the virus were negative.

The owner, Richard Bowden, said he might create quarantine stalls to observe horses after public events.

"We sure don't want our horses sick (nor) everybody else's that are in here," he said.