Thirteen new COVID-19 cases were reported across Simcoe County Friday, for a total of 145 patients this week, the highest weekly case count yet.

With the infection rate climbing week after week, associate medical officer of health with the Simcoe Muskoka health unit, Dr. Colin Lee, says patience is the key to stopping the spread.

"I think that's what's necessary to turn things around," he says. "It takes time for brakes, as example, to stop a fast-moving train. COVID can be a fast-moving train."

Five of the cases listed are among Barrie residents who contracted the virus through the workplace.

The remaining cases are in New Tecumseth, Clearview and Ramara.

Lee says contact tracing is proving to be challenging as the case numbers increase. "If the numbers go up rapidly, it may cause a delay in our ability to catch those who test positive.

"My advice is if you are feeling ill, and you go get tested, the first thing to do is self-isolate at home waiting for your results. If it comes positive, and we haven't got a hold of you yet, keep self-isolating and ask your household members to do the same," Lee says.

The Simcoe Muskoka health unit says most COVID-19 infections are from the Barrie and South Simcoe areas, including outbreaks at four seniors' homes.

Find a COVID-19 testing centre here.