Official statistics published this past week confirm a continuation of the modest uptick in new COVID infections which we reported after the seasonal surge starting last August finally ran its course.
For Ontario, that uptick began in early April and is apparent in firm municipal wastewater testing data but is shown as mostly levelling out in the more recent two weeks, which are estimate as indicated by the dotted line. Actual human PCR test results, however, show a significantly sharper rise in positive diagnoses over the same period. COVID hospitalizations have likewise risen, thought ICU admissions do not yet appear to have followed suit.
The more independent COVID-19 Resources Canada Hazard Index continues to estimate one in 76 Ontarians being currently COVID-infected and hence infectious.
The most recent US Centers for Disease Control estimates of circulating COVID variants summarized in this week’s composite chart are all displayed in shades of blue, denoting JN.1 derivatives. The original JN.1 strain has dropped from 55% down to only 16% over the past eight weeks. Its KP.2 derivative now enjoys the largest single “market” share, having soared from 4% to more than 28% in that same period. That said, the growing family of new strains which began with JN.1 utterly dominates the COVID-19 scene, accounting for more than 99% of all new cases, a dominance which is equally reflected in Canadian data.
The WHO has confirmed that JN.1 is sufficiently antigenically different from the XBB.1.5 family against which currently-available vaccines were formulated as to require a monovalent JN.1 vaccine. We can only hope that such a booster will be made available by August when the next seasonal COVID surge is likely to begin.