CDC estimates how well flu vaccine worked last year–but its numbers don’t support its claims

First, what CDC claims:

During the 2019-2020 flu season, #fluvaccine helped prevent [Notice, they carefully avoid saying “prevented”–Nass] 6,300 flu deaths, or the equivalent of saving about 17 lives per day over the course of a year. Learn more about the burden of influenza and the effects of annual #flu vaccination:

2019-2020 Tables for Influenza Burden and Burden-Averted Estimates
Table 1: Influenza vaccine coverage, by age group — United States 2019–2020 influenza season

Vaccine coverage * Vaccine effectiveness against influenza A(H1N1)pdm09†Vaccine effectiveness against influenza B/Victoria†
Age Group%95% CI%95% CI%95% CI

6 months-4 years


5-17 yrs


18-49 yrs


50-64 yrs


≥65 years


*Estimates from FluVaxView. (12)

†Estimates from US Flu VE Network. (13)

But look at the confidence intervals: three include negative numbers, which show that a) the results are not statistically significant, and therefore the effectiveness numbers are unsupported, and b) it is possible, based on the best studies CDC chose to use, that the vaccine might be associated with increased flu infections.

The Influenza A virus contained in the vaccine is for the 2009 swine flu, which has been around for 11 years, and everyone has been exposed to it, almost certainly engendering a high level of population immunity without the vaccine. Did the vaccine add anything at all to swine flu immunity?

Also interesting, the 2019-2020 flu shots contained 3 or 4 different influenza antigens, depending on the shot. But CDC has omitted information on the effectiveness of the H3N2 component, and of the possible second influenza B component. Presumably they provided even less benefit, and possibly made recipients more susceptible to those viruses. Or perhaps CDC guessed wrong, and those viruses didn’t actually circulate last year. But since CDC decided they should be included in last year’s flu shots, and over 100 million Americans were injected with those antigens, isn’t CDC responsible for letting us know whether those vaccine components were associated with any benefit? Harm?

If you read on in this CDC document, you find out that all the numbers are actually estimates. CDC chooses to gives its estimates using 3 significant figures, as if the numbers are highly accurate, when all they are, are guesses based on models.

I am glad the Trump administration refused to accept CDC’s guesses instead of real numbers for Covid deaths and cases. I am sorry the method that they chose for data collection has not provided the data we all need. Why is it that whether you use the CDC or a private contractor, in the midst of a pandemic, spending lots of money, the White House is unable to obtain accurate information on something as rudimentary as the ages of hospitalized and deceased Covid patients? What exactly is obstructing this simple data collection?
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