At least 11 out-of-towners who visited Deerhurst Resort in Huntsville, Ont. over the August long weekend have tested positive for COVID-19, according to local health officials, and the Simcoe Muskoka District Health Unit is investigating.

During the region's media briefing Tuesday, medical officer of health for Simcoe Muskoka, Dr. Charles Gardner, said the health unit is investigating after a group of about 30 people, consisting of multiple families, visited the resort. 

Some of the tourists also visited 3 Guys and a Stove while visiting the area, one of which has since tested positive. The restaurant is now closed to allow for intensive cleaning and for staff to be tested.

Dr. Gardner said all the individuals reside outside Muskoka and Simcoe County and were asymptomatic while they were visiting, but some of them developed symptoms upon returning home and sought out testing. 

Results then came back positive for 11 of the individuals. 

"We were notified of this by the health units involved, and are in the middle of conducting an investigation about contacts at that site, at those facilities… in order to determine individuals who would need to go into self-isolation and be tested and followed up for further investigation," Dr. Gardner said.

So far, he said they've identified one individual who is deemed to be at high risk and needs to be isolated. 

"We did note that there is a high degree of compliance at those two premises with regards to infection control practices — the mask use and the distancing and the other controls that are necessary for resorts," he said.

"So that certainly helps in this situation, and I think an important takeaway message from this would be that there's the potential for transmission, even in Simcoe, even in Muskoka, even when our rates are very low. The potential still exists and the people need to continue practicing the safety practices that we are always speaking to."

Dr. Gardner said this cluster of new cases should also serve to show how important it is for businesses to maintain safety practices, since it's entirely possible that individuals who have not been diagnosed could enter the premises and practicing mask usage, social distancing and hand hygiene could prevent transmission to both staff members and other patrons.

"It's important to note that to date, we haven't identified any cases of transmission in Muskoka related to this situation," he said. "So of course we continue to investigate and monitor but to date, but there's been no evidence of transmission."