“Rates of influenza have remained persistently low through late 2020 and into 2021, cratering from levels a year ago and raising the puzzling specter of sharply reduced influenza transmission rates even as positive tests for COVID-19 have shattered numerous records over the last several weeks.
Where have all the flu cases gone?
Epidemiologist Knut Wittkowski thinks he can answer the riddle.
‘Influenza has been renamed COVID in large part,’ said the former head of biostatistics, epidemiology and research design at Rockefeller University…
The Centers for Disease Control and Prevention’s weekly influenza surveillance tracker reports that the cumulative positive influenza test rate from late September into the week of Dec. 19 stands at 0.2% as measured by clinical labs. That’s compared to a cumulative 8.7% from a year before.
The weekly comparisons are even starker: This week one year ago, the positive clinical rate was 22%, where now it stands at 0.1%.
Those low numbers continue trends observed earlier in the year in which flu rates have remained at near-zero levels. The trend is not limited to the U.S. Worldwide, health authorities have all reported sharply decreased influenza levels throughout what is normally peak flu season in the northern hemisphere. Rates in the southern hemisphere were also low this year…
Public health officials have at times struggled to explain why positive COVID tests have surged upward in places — such as California, Pennsylvania and elsewhere — where policies such as social distancing and mask mandates have been in place for months.
Data indicate that more than nine out of every ten Americans in most states are wearing masks in public regularly; those numbers have been above 80% since the early fall. Yet average positive COVID-19 tests have multiplied by nearly seven times since the spring peak.
Politicians and health experts have claimed at times that those surging numbers are being driven by individuals who are failing to wear masks and socially distance themselves from others, though such assertions are not often accompanied by much supporting evidence.
A 2019 World Health Organization study, meanwhile, found ‘no evidence that [wearing a mask] is effective in reducing transmission’ of influenza, potentially suggesting that masks may not be playing much role in the currently reduced influenza levels being seen throughout the world.”