Peel Region’s medical officer of health says a more virulent COVID-19 variant of concern will soon become the dominant strain in Peel ahead of any other region in Ontario.

Dr. Lawrence Loh said the B.1.617 variant, which was recently dubbed Delta by the World Health Organization, could displace and overtake the current dominant B.1.1.7 variant, now known as Alpha, within one month.

“Preliminary analysis from the science table suggests that in one month the Delta variant will be the dominant strain in our region with the rest of Ontario weeks behind,” Loh said Wednesday morning during Brampton’s weekly COVID-19 update.

“With initial signals suggesting that the Delta variant is also more transmissible and severe on top of the Alpha variant, this means we very much welcome the province’s continued cautious reopening as one component to preventing a fourth wave,” he added.

The highly-contagious Alpha variant, which was first discovered in the United Kingdom, started to spread throughout the province earlier this year contributing to a significant jump in new coronavirus infections and hospital admissions during the third wave of the pandemic, nearly overwhelming the provincial health-care system.

Daily infections topped 4,000 throughout April prompting the provincial government to issue another stay-at-home order and close down schools.

The Delta variant, which rapidly spread throughout India causing widespread hospitalizations and deaths, was first identified in Ontario later in April.

Recent studies conducted in England suggest that Delta is more transmissible than Alpha, and can cause more severe symptoms in younger adults than earlier strains of coronavirus.

To date, there are at least 97 lab-confirmed cases of the Delta variant in Peel Region and a total of 322 cases in Ontario, according to Public Health Ontario (PHO).

However, PHO has not been able to develop a mass screening tool to easily and quickly detect the Delta variant like it does for other variants, resulting in a slower turnover rate of positive results and an inaccurate picture of how quickly Delta is spreading in the province.

Instead, PHO screens for Delta using whole genome sequencing, where the entire DNA of the sample virus is mapped out in a lab. Currently, the province has the capacity to sequence roughly 2,500 samples per week.

Ontario’s chief medical officer of health has said there is no easy way to screen for Delta using modified PCR testing, which is how the other variants of concern are screened.

While speaking to CP24 Wednesday morning, infectious diseases specialist Dr. Isaac Bogoch, who also sits on the province’s COVID-19 vaccine task force, acknowledged that cases of the Delta variant are growing across the province.

"The variant initially discovered in India... it actually is out-competing B.1.1.7, that's a variant initially discovered in the United Kingdom. And we're seeing this gradually takeover. So, again, what's the answer to this? Vaccinate, vaccinate, vaccinate, which is exactly what we're doing here in Canada,” he said.

Loh said the best method to combat the Delta variant is a combination of a cautious reopening approach and ramping up vaccinations.

“Science is clear that with the new variant, the new Delta variant growing, we need to move quickly to two doses for maximum protection,” he said.

“I understand that these analyses from our science table partners are preliminary, but there is discussion underway to see what it would mean in terms of accelerating second doses in regions such as Peel where the Delta variant is becoming increasingly predominant.”

Loh added that accelerating second doses will help fight a possible fourth wave ignited by the Delta variant.

Last week, the provincial government released its two-dose strategy with residents 80 years and older allowed to start booking their second shot as of Monday. Premier Doug Ford said he expects all residents 12 years and older who want a vaccine to receive their second dose by the end of summer.

-With files from CP24’s Chris Herhalt.