Canadians have been told that coronavirus vaccines will be available to anyone who wants one by September, but experts are warning that the pandemic won’t end overnight.
New COVID-19 variants, various rates of community spread and limited data on the impact vaccines have on transmission can all complicate and vary projections across the country.
“I don’t think Canadians want to do what we’re doing today until October,” says Caroline Colijn, mathematician and epidemiologist and Canada 150 Research Chair in Mathematics for Infection Evolution and Public Health at Simon Fraser University.
“If we rely on vaccination in the current plan and we don’t get to young adults until September, that’s what we’re facing and it concerns me.”
Colijn says current vaccination plans are likely to succeed at protecting those at risk, but aren’t aimed at stopping transmission.
The University of Toronto’s Dionne Aleman, meanwhile, says “things will return to normal in a sort of a slow, phased approach.”
Aleman, a professor of industrial engineering who’s worked on COVID-19 modelling predictions and planning, is hoping for a semblance of normalcy in early 2022 but admits there are “a lot of contingencies.”
Different regions will also have different experiences, as has been the case throughout the pandemic.
“Places that are already having COVID very much under control — like a lot of the Atlantic provinces, for example — will be able to have that return to normal much sooner,” Aleman said.
“Once vaccines start to be introduced, not as much of the population will have to be vaccinated before things can really start to be quite open and quite back to normal,” while more densely populated areas with higher rates of community transmission will likely have to wait longer.
“It’s just a numbers game. There are a lot of people. More people have to be vaccinated, which will take more time in order for us to be able to start being relaxed in the urban areas.”
Vaccines and transmission
Get weekly health news
“We don’t know what is vaccine efficacy against transmission. We know how efficient it is against the serious symptoms and deaths, but not the transmission,” says developmental biologist Malgorzata Gasperowicz, who is also a research associate with the University of Calgary.
Time will tell through additional data if the vaccines are sterilizing, meaning that a person cannot transmit the virus to others, but Aleman says COVID-19 vaccines are beneficial regardless — not just to individuals but to the wider community.
“Even if you can still transmit COVID while having the vaccine, hopefully having the vaccine means that you have an exceptionally mild and hopefully even totally asymptomatic experience with COVID,” Aleman explained.
“And we’ve already seen throughout this pandemic experience that people who are asymptomatic are less contagious than people who are coughing a lot and and other stuff. So that should mean that if the disease is much less transmissible, much less contagious, then it’s not going to spread like wildfire like it is now.”
Children are also another hurdle, as currently only adults are eligible to receive vaccines approved in Canada.
Cynthia Carr, epidemiologist and founder of EPI Research in Winnipeg, says clinical trials looked at symptomatic illness and “it didn’t take a long time to find cases and be able to compare against the vaccinated group.”
“But younger people are much less likely to develop symptomatic illness. So those clinical trials might be more challenged in terms of taking longer to find the difference between symptomatic cases and non-symptomatic,” she said.
“It’s also often very challenging to get parents to allow their children to participate in clinical trials.”
A mutating virus
Another variable? Emerging COVID-19 variants.
Scientists say the new variant identified in South Africa can evade the antibodies that attack it in treatments using blood plasma from previously recovered patients, and may reduce the efficacy of the current line of vaccines.
British Prime Minister Boris Johnson said on Jan. 22 that the COVID-19 variant first discovered in the U.K. may be associated with a higher level of mortality. However, he said evidence showed that both vaccines being used in the country are effective against it.
On Thursday, Novavax reported that its COVID-19 vaccine is the first to show significant results on protecting against the U.K. and South Africa variants at 89.3 per cent effective and 49.4 per cent effective, respectively.
“We know about this South African and UK (variants), because they are the countries who make sequencing. So they sequence many, many, many cases so they can detect it,” Gasperowicz said.
“Many other countries don’t. So there might be variants around that we just are not aware of.”
Currently, Canada is faced with a reduction in vaccine shipments, though the Prime Minister’s Office insists the country will get the promised four million doses of Pfizer’s coronavirus vaccine by the end of March, but even outside of supply, distribution is a challenge.
Aleman says “even if in Canada we suddenly have a huge stash of vaccines that we can just immediately start distributing, we have to actually distribute them to people. And that does just take time.”
Speeding up the timeline
Colijn believes a so-called “return to normal” depends heavily on what Canadians are willing to do to get there.
“Until most of us are immune or until we’re willing to use technologies or until we’re willing to do the New Zealand, the COVID Zero thing, it’s going to be a while before we’re out of this,” she said.
“We need to be stopping transmission in some other way than asking everybody to stay home forever. We need to be stopping transmission with rapid testing, with massive population screening.”
Carr agrees that vaccines are just one tool in the toolbox, but she was cautious about rapid testing. She says many tests “are quite limited when somebody does not have symptomatic disease.”
Gasperowicz is a supporter of the COVID Zero approach, which involves fairly strict measures in place until community transmission reaches zero.
“For me, the painful thing is that it’s really achievable to eliminate the local transmission and have life like people had in Atlantic Canada, in northern territories, in Australia, in New Zealand,” said Gasperowicz.
Regardless of the variables at play, Colijn believes an end is in sight.
“COVID will be with us for years, but I don’t think we’ll be in the current mode for years and I think there will be a way largely out of this, hopefully by late fall.”
— with files from Global News’ Su-Ling Goh, David Lao and Rachael D’Amore as well as Reuters’ Andy Bruce, Alistair Smout, Guy Faulconbridge, and Kate Holton.
Comments