The statistical indicators which we use to gauge pandemic severity remain mixed, suggesting that the seasonal surge of new COVID infections to which we have been subjected since mid-August is continuing but not significantly worsening.
PCR testing of municipal wastewater remains the most reliable indicator of infection rates. As you can see in this week’s composite chart, the most recent Ontario COVID viral counts are now at their highest level for this entire year, and continue to accelerate. PCR COVID test positivity among the minority of those still eligible, hospitalizations and ICU admissions, however, have all plateaued at high levels. Those statistics suggest that most infected people are no longer bothering to be tested and their symptoms tend to be milder than in the past, likely due primarily to some degree of protection from residual immunity gained in previous infections.
The biweekly forecast from COVID-19 Resources Canada is unchanged from last week, with an estimated one in every 41 Ontarians being currently infected with COVID and therefore infectious. This remains worrisome in light of the typically large increase in unprotected close contacts during the coming holiday weeks.
As for currently-spreading variants, the latest Public Health Canada data are quite similar to what we reported last week from the US CDC. The EG.5 subset of the XBB family of recombinants remains just barely dominant, with a 53% Canadian “market share”. More specifically, the HV.1 strains of that subset accounted for 37% of all new cases. Their main competition, however, are the new and much more rapidly spreading JN.1 lineages which are not at all XBB-derived. Rather, they are the much-mutated progeny of BA.2.86. With much of our current “herd immunity” based on XBB-formulated vaccine boosters as well as previous XBB bouts over the past year, there is lots of scope of reinfection. The only good news is that most of those infected continue to experience relatively moderate symptoms.