COVID variants now dominating local case counts, says medical officer of health

·3 min read

A recent rise in local COVID-19 cases — combined with the increasing percentage representing variants of concern — emphasize the need to maintain control measures to avoid a third wave of infections, says Simcoe-Muskoka’s medical officer of health.

“We have a great opportunity right now with immunizations,” Dr. Charles Gardner said on Tuesday during his weekly media briefing. “We’re at a point now where we want to get ahead of the pandemic and not have it swell into another wave while we achieve protection for everybody with immunization and bring us into another place in the spring and into the summer.”

During the week of March 7, the variants represented 73 per cent of all COVID cases. That’s up from 54 per cent the week of Feb. 7. Provincially, variants of concern represent 49 per cent of all COVID-19 cases.

Gardner said that’s a significant jump in the proportion of our cases that are variants of concern.

“We’re really getting to the point now where we’re considering variants of concern to be the dominant element of our COVID cases,” he said. “When we’re talking about COVID, we’re essentially talking about variants of concern in Simcoe-Muskoka.”

On Tuesday, the health unit reported 850 cases have been identified as variants in Simcoe-Muskoka — 171 of them continue to be active.

Sequencing tests have confirmed 252 cases of the B.1.1.7 variant from the UK have been identified. There have also been seven cases of the P.1 variant that first originated in Brazil, and one case of the B.1.351 strain that originated in South Africa.

All three strains are considered more transmissible. In addition, Gardner said the B.1.1.7 variant may also be more severe in its impact and be more contagious.

In addition, there are concerns that the B.1.351 or South Africa variant might have some degree of resistance against the AstraZeneca vaccine, which is being targeted to those aged 60 to 64.

“There’s still significant response to that vaccine from that variant, but some research has demonstrated that it’s reduced,” he said. “So increased transmissibility of these variants of concern, the potential for at least one of them to be more severe is of concern and we certainly need to continue to monitor the impact of these variants on the responsiveness of immunization.”

Gardner identified ongoing variant surveillance as an important tool. Although now that the greatest majority of cases locally are considered to be variants of concern, there will be an assumption that, going forward, all or most of the cases will be one of the variants, he said.

The tests for all three variants take about the same time, but Gardner said there are upgraded testing methods in the works which are quicker, more efficient and less costly.

Instead of genetic sequencing of all the cases coming back positive for COVID-19, a second genetic marker can help sort out the specific variant and that reduces the number of isolates that need to be genetically sequenced.

And while wastewater testing has helped to monitor the degree of COVID-19 in the community there is less value for the test specifically for the UK variant, given that the variants are dominating here.

Marg. Bruineman, Local Journalism Initiative Reporter, barrietoday.com