(Adds background on vaccination)
By Allison Martell
TORONTO, March 11 (Reuters) - New variants of the coronavirus are spreading rapidly in Ontario and unless they are better controlled, the province risks facing a third wave of the COVID-19 pandemic, an expert panel advising the province's government said on Thursday.
It warned that the next few weeks are critical as the progress made in bringing the coronavirus under control in the province has stalled.
"Variants of concern continue to spread across Ontario. Our ability to control the rate of spread will determine whether we return to normal or face a third wave of infection," the panel said in briefing material.
While mutations in viruses are inevitable, strains identified as "variants of concern" have worrisome changes that may give the virus advantages, increasing transmissibility or reducing the effectiveness of vaccines, according to the briefing materials released by the province's science advisory and modeling consensus tables.
Graphs published online ahead of the briefing showed cases of the new variants in Ontario have jumped from below 5 per 100,000 residents each week in early February to nearly 20 per 100,000 residents each week in early March.
That increase has been balanced to some extent by a decline in cases of earlier variants of the virus. (https://covid19-sciencetable.ca/ontario-dashboard/)
Adalsteinn Brown, co-chair of the science advisory panel, said there are effectively two separate epidemics in Ontario: Early variants of the virus are under control, but new variants are not.
The Canadian government designated Thursday a National Day of Observance to commemorate lives lost and "the significant impacts" of the pandemic, which has killed more than 22,000 in Canada.
The country's vaccination campaign is off to a slow start compared with other rich nations, with just under 2.7 million doses administered to a population of 38 million as of Thursday, according to volunteer-run tracking site COVID-19 Tracker Canada. (Editing by Chizu Nomiyama and Giles Elgood)