Canada monitoring ‘whole slew’ of variants, says chief public health officer

OTTAWA — Chief public health officer Dr. Theresa Tam says the latest variant of interest in the COVID-19 pandemic has popped up in Canada in small numbers, but it’s too early to know how widespread it is or what impact it could have.

Tam says 11 cases of the Lambda variant that was first identified in Peru last year have been reported to Health Canada to date. However, the National Institute of Public Health of Quebec said Thursday it has confirmed 27 cases already, all in March and April.

Lambda is just one of a “whole slew” of variants the Public Health Agency of Canada is keeping an eye on, said Tam, and watching how much is it spreading and how it will respond to vaccines.

“We’re just trying to gather up some information on who it is that’s having the Lambda variant right now, but there’s very few cases at this point,” she said.

Angela Rasmussen, a virologist at the University of Saskatchewan’s Vaccine and Infectious Disease Organization, said there has been a pattern of panicking that vaccines won’t work every time there is a new variant.

“It’s like ‘Oh no, new mutations,’ but actually Lamda doesn’t really have new mutations, it just has new combinations of mutations that we’ve already seen before,” she said.

Early studies, including one from New York University published July 2, suggest Lambda may be a bit resistant to antibodies produced by the mRNA vaccines from Pfizer-BioNTech and Moderna, but concluded it is not by enough “to cause a significant loss of protection against infection.”

Rasmussen also said most vaccine tests on variants are done in labs, not people, and give an incomplete picture of how immunity from vaccines work, including T-cells, which are separate from antibodies but also help kill viruses.

Rasmussen is part of a new network of Canadian scientists that launched this week specifically to collaborate on studies of COVID-19 variants.

The Coronavirus Variants Rapid Response Network, known informally as CoVaRR-Net, is funded by the Canadian Institutes of Health Information. It has already launched eight different studies to see how variants are spreading in Canada, including wastewater monitoring for variants in four major cities, and closer looks at how they are responding to vaccines.

They also have a project to develop better education for the public about what variants are and how they affect the pandemic.

Rasmussen said people really need to understand that mutations and variants are a normal evolutionary process. Viruses spread by making copies of themselves inside human or animal cells, and most of those copies aren’t perfect.

Sometimes, the virus gets lucky and the mutation makes it stronger, said Rasmussen. That can mean it infects people more easily, it could make you more sick when it does infect you, or, and this is perhaps most worrying to many, resist vaccines.

A variant is labelled as being “of interest” if it suspected of doing one of those three things, and has been found in multiple places. It is elevated to being “of concern” if any of those suspicions are confirmed.

The World Health Organization has confirmed four variants of concern — Alpha, the B.1.1.7 variant first identified in the United Kingdom, Beta, the B.1.351 variant identified in South Africa, Gamma, the P.1. variant identified in Brazil, and Delta, the B.1.617.2 variant identified in India.

There are four variants of interest being monitored by WHO as well, of which Lamda is the most recent designation. It was first discovered in Peru in August 2020, but was classified by WHO as a variant of interest in mid-June.

Lambda has so far mainly been found in South America, where it is becoming the dominant variant.

Tam said one thing that isn’t clear yet is whether Lamda will be able to replace the other variants that are already dominant in Canada. Alpha, which is about 50 per cent more transmissible than the original virus, is responsible for almost 90 per cent of the 250,000 confirmed variant of concern cases in Canada to date.

Delta, which is about 50 per cent more transmissible than Alpha, is now slowly overtaking Alpha in some places, including Ontario. Nationally there are 4,654 Delta cases are confirmed, up from about 2,000 on June 18.

Tam said Alpha and Delta didn’t get much of a foothold in South America before Lambda arrived and it’s not clear if they would have snuffed it out if they had.

“I don’t really know how Lambda will play out in the population that already is occupied, for example, by the Delta variant and you know, the race between them,” she said.

This report by The Canadian Press was first published July 8, 2021.

Mia Rabson, The Canadian Press