FALLS CHURCH, Va. (AP) — A coronavirus outbreak at a northern Virginia long-term care facility has resulted in 11 deaths and dozens of illnesses over the past month.

The outbreak at Dulles Health and Rehab Center in Herndon began with a positive test for the coronavirus March 28, said Jeannie Adams, director of legal services for Commonwealth Care of Roanoke, which provides management and consulting services to the Herndon facility.

Since then, there have been 63 positive test results of patients at the facility. Of those, 47 are still receiving care there.

Adams said Wednesday that 19 staff members have also tested positive.

Virginia authorities have reported 91 outbreaks at long-term care facilities across the state, resulting in 78 deaths.

The most serious outbreak occurred at Canterbury Rehabilitation and Healthcare Center in Henrico County near Richmond, where more than 45 patients died.

Adams said the Herndon facility has been working closely with officials from the Fairfax County Health Department, which she said has provided “invaluable support, instruction and direction.”

The 11 deaths at the Herndon facility were first reported by WRC-TV in Washington on Tuesday.

County officials declined to comment on the Herndon outbreak. In general, state and county health officials have declined to release details about outbreaks at specific private facilities, though aggregated statistics about outbreaks are updated on a regular basis.

Thus far in Virginia, authorities have reported more than 10,200 cases in the state. That’s more than 600 new cases in the last 24 hours. The death toll increased Wednesday from 324 to 349. The new numbers Wednesday were delayed by a glitch, according to the Virginia Department of Health.

For most people, the coronavirus causes mild or moderate symptoms, such as fever and cough that clear up within weeks. For some, especially older adults and those with existing health problems, it can cause more severe illness and death. The vast majority of people recover.