Public Health Ontario has re-examined every COVID-positive test sample involving international travel since the beginning of November in search of information about how long the Omicron variant has been in the province.
So far, it has found no sign that the variant was present in Ontario before the first cases were identified in Ottawa last weekend. Two more Ottawa cases have since been confirmed. All four patients travelled in Nigeria before returning to Ottawa.
The highly mutated variant was discovered in South Africa in late November. Global health officials say it is still too early to have solid evidence about how sick it is likely to make people compared to previous variants and how well existing vaccines will work against it. Some of that preliminary information is expected “in days, not weeks,” officials with the World Health Organization said Wednesday.
It has put the world on alert because it contains so many mutations compared to previously identified variants. More than 30 mutations are on its spike protein, raising concerns that it could be better at evading immunity from vaccines and previous infections.
In his first comments about the variant, Premier Doug Ford called its presence in Ontario “a cause for concern, but not a cause for panic.”
He encouraged more Ontarians to get vaccinated and applauded the federal government for travel restrictions and testing requirements for international travel.
“Every day we learn more about the Omicron virus, about how quickly it can spread and how severe it may be. We’re learning about how effective our vaccines are, and every day that we hold off more cases entering our country, the more time we have to learn and prepare,” he said.
“We cannot allow anything to jeopardize the gains that we’ve made,”
All 375 people who returned to Ontario after travelling to various African countries on the travel restriction list are being tested and quarantined until the result are know, Health Minister Christine Elliott said.
The epicentre of the new variant remains in South Africa, where case counts are rising rapidly. Cases have also been identified around the world. Some countries have found evidence that the newly identified variant has been there for a while, but, until it was genetically sequenced by South African scientists, countries weren’t looking for it.
Public Health Ontario did not find evidence that has been the case in Ontario, but, since all international travellers have not been routinely tested until now, cases could also have been missed.
It is likely that more cases will be identified in Ontario as the variant spreads and testing is expanded over the coming days.
By next week, Ontario’s COVID-19 Genomic Network expects to screen all eligible COVID-19 positive samples for the presence of the Omicron variant using a separate PCR test, Public Health Ontario said in a statement. That test will be conducted on all positive samples “to provide more targeted and rapid identification of suspected Omicron cases and to help prioritize samples going for whole genome sequencing.”
It can take up to 10 days for genome sequencing results to confirm the screening, but the initial screening results can be back in 24 to 48 hours. Public health officials do contact tracing no matter which variant is found.
In Ottawa, and elsewhere across the country, scientists are working frantically to learn more about the variant and its likely impact within Canada.
Dr. Marc-André Langlois, a molecular virologist at the University of Ottawa who leads Canada’s Coronavirus Variants Rapid Response Network (CoVaRR-Net), said researchers were waiting for samples of the cells to grow in a lab so they could be studied to see how the various combinations of COVID-19 vaccinations within the Canadian population responded to the variant, among other research. It is important for such Canadian-specific work to be done, he said, in part because Canada has mixed vaccines which many countries have not done.
Ottawa’s COVID-19 Testing Taskforce and Ottawa Public Health said in a statement that provincial and national public health laboratories collaborated to confirm the positive Omicron tests of four travellers arriving in Ottawa.
Later this week, the Eastern Ontario Regional Laboratory Association will expand local variant of concern testing of all positive PCR tests, which will identify variants that are not Delta and could be Omicron. They will be prioritized for full genomic sequencing, which should get results back more quickly.
With files from the Canadian Press