BARRIE, ONT. -- Ontario added Simcoe Muskoka to the list of 10 hot spots across the province for the Delta variant on Thursday, but with just 18 local cases identified as the B.1.617.2 variant, it begs what went into the decision?

Simcoe Muskoka's associate medical officers of health says it all comes down to basic math.

According to Dr. Colin Lee, the region is in the top 10 of 34 Ontario health units with data showing 15 to 20 per cent of COVID-19 cases that classify as the Delta variant.

DELTA VARIANT IN OUR COMMUNITIES

Still, the local doctor says the variant appears to be under control.

"For the last three weeks, it's been fairly stable, so it hasn't taken off. It isn't going at an accelerated speed," Lee says. "It's not that many Delta variant cases out there to infect others."

The health unit reports 669 COVID-19 tests screened positive for a variant of concern; however, they require further testing to confirm the strain.

Health officials believe the Delta variant will become the dominant strain of COVID-19 in the coming weeks, even months. "But as long as the number of cases are low, that will prevent like a take-off to a potential fourth wave," says Lee.

VACCINES CAN SLOW THE SPREAD

Lee expects the health unit to receive double its regular shipment of vaccines in the next few weeks, with 20,000 doses of Moderna in addition to the 30,000 doses of Pfizer.

Lee says stopping the spread of the virus is "within our grasp," adding vaccines are the best defence. "We just want to encourage everyone to get their second doses," he says. "It's really a race between our vaccination versus Delta variant."

"Get a first dose into those who have not been immunized and at the same time get everyone 18 and over a second dose as quickly as possible," he adds.

Nearly 63 per cent of Simcoe Muskoka residents have received their first doses of the vaccine, and about 17 per cent of adults have had both doses.

SECOND DOSES

As a hot spot, Ontario expanded second doses to Simcoe Muskoka adults 18+. Starting Wednesday, residents who had their first mRNA vaccine on or before May 30 can book their second vaccine.

Complete information on second doses is available here.

"We're in the final corner," Lee concludes. "I think that is the first time I said that, but I think we're truly in the final corner."

With files from CTV's Dana Roberts