Thread by @Aaron_Derfel

1) Montréal’s public health director said Wednesday the city was entering a “transition phase” amid falling #COVID hospitalizations. But 10,500 kilometers away, South Korea's prime minister was appealing for calm amid an unprecedented spike in cases. montrealgazette.com/news/local-new…

2) In just four days, the number of declared #COVID infections in South Korea has soared from 100,000 to more than 171,000 – that nation's highest by far than at any other point in the #pandemic. “There is no reason at all to fear or panic,” Prime Minister Kim Boo-kyum said.

3) South Korea has now surpassed the United States in its rate of new weekly #COVID hospitalizations, at a rate of 201.81 per million population compared with the U.S rate of 138.18. This is astonishing given South Korea’s Zero COVID approach in dealing with the #pandemic.

4) South Korea confirmed five cases of the original Omicron variant of concern on Dec. 1. By Dec. 22, the nation of nearly 52 million marked its deadliest day in the #pandemic, with 109 #COVID deaths declared. Deaths then started to trend downward until the beginning of February.

5) Pandemic deaths started rebounding there Feb. 7. At a seven-day average of 0.90 deaths per million on Feb. 19, South Korea’s rate is far below the U.S.’s rate of 6.53, but it’s surging. Why is this occurring now? Could it be related to the #Omicron stealth sub-variant, BA.2?

6) Korea News reported Monday the prevalence of BA.2 in South Korea rose to 4.9% from about 1% two weeks earlier, likely an underestimate. By comparison, the Centers for Disease Control notes that BA.2 currently accounts for 3.8% of circulating SARs-CoV-2 lineages in the U.S.

7) In Denmark, the more contagious BA.2 sub-variant accounted for nearly half of all new cases on Jan. 20, according to the Statens Serum Institut. BA.2 prevalence has risen to more than 66% since then, prolonging the Scandinavian nation’s ongoing surge of #COVID deaths.

8) South Africa has recorded the highest BA.2 prevalence in the world at more than 86%. It’s likely BA.2 also extended the Omicron death wave in that country, but the impact has not been as severe, perhaps because of its much younger population (only 5.5% are over the age of 65).

9) Which brings us back to Québec. Dr. Mylène Drouin, head of Montréal public health, noted BA.2 represented less than 10% of new #COVID cases in Québec, well below the 15% estimate of her boss more than a week ago, but still almost triple the U.S. percentage. That is indeed odd.

10) Since Québec is no longer screening for the #coronavirus to the extent it used to, one wonders how Drouin could arrive at a BA.2 prevalence of about 10%, which would be double the prevalence in South Korea, which had already gone through a first Omicron wave in December.

11) More likely, the experience in Denmark and now South Korea suggest the full impact of BA.2 may not yet have been felt in Québec, the rest of Canada or the U.S. Yet Québec will continue lifting public health protections, including school masks as of March 7. End of thread.