Ontario reports 270 new cases of COVID-19 as officials remind mRNA vaccines provide 'equal protection'

Ontario reported another 270 cases of COVID-19 on Monday, the fewest on a single day in more than nine months, as more people in the province become eligible for a second dose of a vaccine.

New cases continue to fall week over week

Appointments for a second shot of COVID-19 vaccine opened this morning to anyone who got a first doses of an mRNA vaccine on or before May 9. (Frank Gunn/The Canadian Press)

Ontario reported another 270 cases of COVID-19 on Monday, the fewest on a single day in more than nine months, as more people in the province become eligible for a second dose of a vaccine.

As of 8 a.m. Monday, anyone who got a first shot of an mRNA vaccine (Pfizer or Moderna) on or before May 9 can book or reschedule their second dose, several weeks ahead of schedule.

Similarly, residents of 10 provincially-designated hot spots for the delta variant of concern who got a first dose before May 30 can move up their second shot on Wednesday. 

In a news conference Monday, Ontario's Chief Medical Officer of Health Dr. David Williams said the low case count is primarily attributed to the impact of vaccinations.

"It's the lowest case count we've seen in a day since Sept. 15, 2020," Williams said. "It shows how effective the vaccination program is and will be."

Ontario has administered 12.8 million doses, and three million Ontarians have received their second shot.

"It's going really well, one of the best performers, even on a global perspective," Williams added.

Williams reiterated that mixing mRNA vaccines, Pfizer and Moderna, is "effective and safe."

1st dose protects against hospitalization, 2nd against transmission

While the first dose protects against hospitalization, both Williams and Ontario's chief coroner Dr. Dirk Huyer said the second dose is necessary to protect against transmission.

"Unfortunately, one in four haven't got their first dose," Huyer said. 

Williams said the province is "following the course" but it "cannot let a steady decline in cases give us a false sense of security."

He warned of the delta variant's potency, especially in unvaccinated people, and again urged Ontarians to get vaccinated as soon as possible.

The list of delta variant hot spots includes:

  • Toronto
  • Peel Region
  • York Region
  • Halton Region
  • Durham Region
  • Waterloo Region
  • Hamilton
  • Wellington-Dufferin-Guelph
  • Simcoe Muskoka
  • Porcupine

A shipment of Pfizer vaccines expected to arrive this week will be delayed several days, the Ministry of Health said over the weekend. As a result, many public health units will be offering only Moderna for second shots this week as more than one million doses landed in the province on Friday,

Some health experts are urging Ontarians to consider the two mRNA vaccines interchangeable. 

After hearing anecdotally that some people are walking away from their second dose appointments because they prefer Pfizer over Moderna, Huyer reiterated that the two mRNA vaccines "provide equal effective protection.

Pfizer, Moderna provide 'equal protection'

"Both mRNA vaccines are made with the same research and technology, delivered in the same way, same effectiveness, same side effects, same mechanism," he added.

"With this week's delayed Pfizer vaccine shipments, I'm concerned about people delaying dose 2 because they are being offered Moderna vaccine. The last thing we want is any loss of momentum in our flourishing vaccine rollout," Dr. Jeff Kwong, an epidemiologist with the University of Toronto, said on Twitter.

Kwong said analyses of data compiled by the independent research organization ICES show that two doses of Moderna are "just as good" as two of Pfizer in preventing infections.

As a result, he said, "no reason to think that Pfizer for dose 1 + Moderna for dose 2 would be any worse than 2 doses of Pfizer," he tweeted.

"So if you got Pfizer for dose 1 and are being offered Moderna for dose 2, rest assured that you are doing the right thing by getting it (and not waiting for Pfizer)."

Other experts expressed similar sentiment, noting people regularly get different brands of other vaccines without thinking twice about it.

"Just a reminder — if you got a flu shot this year, you likely don't know the brand. Neither do I. They're made by separate companies," Dr. Zain Chagla, an infectious disease specialist at St. Joseph's hospital in Hamilton, said in a tweet.

"Moderna and Pfizer are interchangeable."

7-day average of cases falls to 334

Today's case count is down from last Monday, when Ontario logged 447 new infections. Due to the cyclical nature of testing in the province, it's best to compare same days of the week.

Labs completed 13,828 tests and Public Health Ontario reported a test positivity rate of 2.5 per cent, higher than in recent days but not unexpected given the low overall number of tests that were processed. Positivity is also down from last week, when the province saw 2.8 per cent on roughly the same amount of tests.

As the Centers for Disease Control in the United States is considering a potential third booster shot in the fall, Williams said booster doses are only necessary if there is a drop in immunity levels.

"We have received no recommendations on that matter," Williams said. "We'd like to see evidence of that." he added, noting that NACI, the federal government, and the province are reviewing the matter.

As the province slowly expects to move into step 2 of its reopening plan, Williams said "society-wide rules on masking" will be looked at given concerns with possible new variants from other countries, which still fighting potent waves of the virus.

"We'll advise in due time," Williams said about when Ontarians can stop wearing their masks, but it is not expected until after Step 3.

The seven-day average of daily cases, one of the most important indicators of the pandemic's growth or decline, fell to 334, its lowest point since mid-September 2020.

As of yesterday, there were 323 people with COVID-related illnesses being treated in intensive care units. Of those patients, 202 needed a ventilator to breathe.

The Ministry of Health also recorded the deaths of three more people with COVID-19, pushing the official toll to 9,022.

With files from Lucas Powers and The Canadian Press


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