Just as vaccines are beginning to protect older people, considerably more contagious — and possibly more deadly — COVID-19 variants are creating a “complex” situation in Canada, according to the country’s top doctor.
Dr. Theresa Tam said Tuesday that rates of cases linked to virus variants, particularly the B.1.1.7 variant, are now highest among younger age groups.
“There is much stronger evidence come out of the United Kingdom and elsewhere to say that this B.1.1.7 variant does result in more severe illness, and it does so across the age groups. So, more severe illness in the elderly, but also in the younger age groups,” she said.
“As soon as you get more numbers of people, you’re going to see more severe outcomes.”
Evidence that the B.1.1.7 variant is more lethal continues to grow. New research links the variant, first discovered in the U.K., to a higher risk of hospitalization and death. One study, published by the journal Nature, suggests the strain is, on average, 55 per cent deadlier than earlier versions of the virus.
There was already evidence the variant is more contagious. Depending on how it’s measured, it can be anywhere between 40 and 70 per cent more transmissible than the original strain.
Experts worry this variant will drive a third surge of infections in Canada.
The so-called “lagging indicators” of the pandemic’s severity — rates of hospitalizations and ICU admissions — have “levelled or increased” over the past two weeks, Tam said. But instead of those numbers being driven by the most vulnerable to COVID-19, Tam said the increased infection appears highest among younger people.
By contrast, data from some provinces suggests rates of infection have declined among those aged 80 and older. That age group is among some of the first to be vaccinated in Canada, Tam noted, particularly those in long-term care facilities.
“If the (variant case) numbers increase in the younger population, I think we’re going to see increases in hospitalizations and ICU visits in those age groups,” Tam said.
“Whether the vaccine has had an effect, that’s an important question. I don’t think we can say for certain… We need to be careful. It’s possible to see an increase in disease severity in any age group with these variants.”
Some provinces have reported a rise in COVID-19 cases among younger adults in recent weeks.
B.C.’s provincial health officer, Dr. Bonnie Henry, warned Monday that serious cases of COVID-19 are increasing among younger residents. She said the virus is spreading through households and workplaces, and that cases are rising among people between the ages of 20 and 30, and up to age 59.
“With a higher number of people in that age group being affected, the probability that somebody is going to end up in hospital at a younger age goes up,” Henry said at a news conference.
Many of the active cases in Ontario currently make up the same age demographic, with the highest group being people age 20 to 29. Variants are believed to be behind much of that growth.
The changing patterns come up against a slowly burning vaccination effort — so far only focused on the elderly or, in some cases, those between 60 and 65. The most recent federal data shows only about 6.8 per cent of the population has received at least one dose of a COVID-19 vaccine, and only about 1.57 per cent has received two.
“It reminds us of how tight the vaccine versus variant race is,” said Tam.
— with files from the Canadian Press