BARRIE, ONT. -- The County of Simcoe is trying to figure out how only one of its 147 residents at Sunset Manor in Collingwood tested positive for COVID-19.

"There does not appear to be a connection with our positive staff result," said Jane Sinclair, health and emergency general manager, County of Simcoe.

The long-term care home has been in outbreak status since a nurse became infected with the virus. The county said the nurse last worked in the facility on Nov. 4, and tested positive over the weekend.

The facility's 172 staff members have since been swabbed for COVID. So far, 160 have tested negative, while 12 are pending.

The infected resident is a woman in her 80s who recently visited a local hospital and went into isolation upon returning to the home.

Sinclair said the woman has no symptoms and is being retested. "Our partners at the health unit really want to rule out the possibility that this is not an active, positive case."

The virus has an incubation period of five to seven days, which has since passed at the home, so county officials are now monitoring residents and staff for any symptoms of COVID-19.

Meanwhile, the county reports there are no new cases at Simcoe Manor in Beeton. There hasn't been a positive staff case in a week or a positive resident case in nine days.

At the peak of the Beeton home's outbreak, 10 residents died after contracting COVID-19.

The county-run facilities represent two of the five outbreaks at seniors' homes across the region.

Barrie's Allandale Station Retirement Residence, Waterford Retirement Home and I.O.O.F. Seniors' Home have had no new cases Thursday.