Lack of serious COVID-19 illness or deaths in two major outbreaks show vaccines are working, experts say

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Forty-three Quebec and Manitoba nursing-home residents infected in two coronavirus outbreaks, after receiving a first dose of vaccine, had minor symptoms or none at all, officials in both provinces say.

Immunologists say the lack of serious COVID-19 illness or deaths in the two major outbreaks in Winnipeg and Gatineau, Que., shows that the vaccines are working.

“This appears to be consistent with what the trials showed about how the vaccines would perform. The vaccines are doing what they are supposed to do,” said Jennifer Gommerman, a professor of immunology at the University of Toronto. “The fact there are no severe cases after just one dose with this many vulnerable people is pretty positive. These are really outstanding, amazing vaccines.”

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Most nursing-home residents in Canada have received at least one shot of the two-dose vaccines. Provincial statistics show infection, serious illness and deaths have plummeted since. In Alberta, cases in long-term care have dropped 92 per cent since Christmas. British Columbia had 16 cases in long-term care last week, down from 485 weekly cases in early December. In Ontario, active long-term care cases among residents fell from 1,650 to 105 in the past month. Manitoba and Quebec experienced similar drops.

The Pfizer-BioNTech and Moderna vaccines used in Canada are 95-per-cent effective at preventing mild or serious illness after two doses. Preliminary evidence suggests they are also quite effective in the short-term after one dose.

They also appear to cut down the chances of being infected at all, but that’s less clear. It is also unknown exactly how much the vaccines might prevent people from spreading the virus.

About 96 per cent of the residents at the Lionel-Émond nursing home in Gatineau were vaccinated in December, but only about 41 per cent of staff. The cases were discovered early this week after scheduled asymptomatic testing at the home. Several staff members also tested positive. Officials suspect workers infected the residents.

“The residents are doing well, with few or no symptoms,” said Benoît Major, director of senior support at the Outaouais health district.

In Winnipeg, residents of the Actionmarguerite St. Boniface home received their first doses Jan. 27. Two weeks later, an outbreak was declared and 20 residents subsequently tested positive. One woman died 24 hours after her positive test result. Charles Gagné, CEO of the home, said the woman was frail and “at the start of end of life” before the outbreak began.

The rest of the residents are stable, he said. “Some of them have a few symptoms, some intermittent fever. We are optimistic,” Mr. Gagné said. “It’s nothing like the outbreaks we have seen in other homes in Winnipeg. It certainly seems like the vaccine is helping but it’s not definitive.”

The short time between injection and infection in the Winnipeg case means the vaccine just started to take effect when the infections happened. “Even three weeks is a little on the edge of how long it would take to mount a strong response,” Dr. Gommerman said.

Residents at the Winnipeg home got their second doses on Wednesday. Residents of the Gatineau home are scheduled to get the booster in mid-March.

Tania Watts, a professor of immunology at the University of Toronto, said it is vital that people get their second doses, particularly older people. The booster shot strengthens and increases the antibodies people make, improves how well the body eliminates virus and lengthens immune response.

“If you haven’t had your second dose and you are over 80, you still have vulnerability. Partial immune response is good but it doesn’t seem to be perfect,” Dr. Watts said.

She said two doses are also more likely to protect against the new variants of concern that are spreading in much of Canada.

Two employees tested positive in the Winnipeg outbreak. As with the Gatineau flareup, Mr. Gagné said the outbreak started with unvaccinated employees, “a small percentage” of whom have received a first dose.

Josée McMillan, president of the union representing Outaouais personal-care, kitchen and maintenance workers, said many of her members are hesitating to take the vaccine. “It really hasn’t gone according to plan,” she said. “It’s disappointing.”

Ms. McMillan said many members do not have confidence in the vaccine because of how quickly they were developed or are hesitant because of the Quebec government’s decision to delay the second dose up to 90 days, four or five times longer than manufacturer recommendations.

“We are encouraging our members to get vaccinated every chance we get, but I can’t hold their hands and make them get vaccinated,” Ms. McMillan said.

Ms. McMillan said governments are going to have to mobilize information campaigns to overcome vaccine hesitancy. “If our people are this hesitant, there are a lot of people in the general population who will be too,” she said. “This is a society problem, not just a worker problem.”

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