Given that the Canadian COVID-19 Resource Canada COVID hazard index hasn’t been updated in the past four weeks and no explanation has been given, I’m now assuming that they are no longer publishing. For our weekly composite graph, I have substituted the Public Health Canada national summary of municipal wastewater COVID viral counts. Wastewater testing used to be the best leading indicator of changes in the rate of COVID infections but the provincial data used to compile it are far from ideal. The Ontario numbers are the least comprehensive because they are now compiled from only four wastewater processing stations, all of them in Toronto. The main value of this chart, therefore, is to provide a rough sense of upward or downward national trends in new COVID infections.
For Ontario, the rate of positive PCR test results is a more accurate indicator, even though it is compiled from the small minority of people who remain eligible for PCR testing. That data, for the week ending on June 14, along with the rates of COVID hospitalizations and ICU bed occupancy, indicate that new COVID infections remain slightly higher than the seasonal low of a few weeks ago, but have not as yet started to climb very noticeably.
Both Public Health Canada and US Centers for Disease Control now report on the relative “market shares” of currently-circulating COVID variants only every other week, unfortunately on the same date. This week’s composite chart shows the Canadian version to June 15. The new NB.1.8.1 strain is now dominant in both countries, having in the most recent two months soared from 8% of new Canadian infections to 54%. During that same period, the even newer XFG recombinant strain grew faster, from less than 2% to almost 19%. It will be interesting to see whether NB.1.8.1 can hold onto dominance for another month or is overtaken by XFG.