The latest data show that the seasonal surge of new COVID infections which began in August continues to rise, but appears to be on the verge of plateauing. As illustrated by our composite chart, COVID viral counts from PCR testing of municipal wastewater are already at their highest level since mid-January and still increasing. That rise is mirrored by positivity rates among the minority of Ontarians still eligible for definitive PCR tests. Previously-soaring Canadian rates of COVID-related hospitalizations and ICU occupancy have, however, plateaued in the most recent statistics.
As discussed in last week’s blog, the most useful metric for managing our personal risk of contracting COVID is the number of infectious people we might encounter in any given day. The COVID-19 Resources Canada forecast for the two-week period ending November 3 estimates one in every 23 Ontarians being currently infected. The statistical basis for their estimate is: wastewater virus counts and PCR infection rates being 17.5 times higher than at the pandemic’s lowest point); Long COVID cases 12.8 times higher; COVID hospitalizations and ICU occupancy (10.9 times higher) and deaths (20.3 times higher). Our actual risk of close contact with an infected person in indoor spaces is likely somewhat less than that because many infected people will test themselves once they become sufficiently symptomatic and stay home, but not necessarily for the recommended 10 days.
The latest Canadian data on circulating COVID variants (to October 28) tracks the relative “market shares” of the 25 most prevalent strains, all of which stem from XBB recombinant Omicron family which first emerged late last year. The EG.5 family of subvariants which appeared in February is now dominant in Canada, accounting for nearly two-thirds of new infections. It has already differentiated into some 50 identified strains, some of which are outcompeting the original EG.5 by virtue of being better able to bypass waning Canadian immunity from past vaccinations and COVID bouts. The currently-most-successful EG.5 strain is HV.1, which now accounts for half of new Canadian COVID infections.