This 2017-18 flu season study does not include COVID-19

We have debunked plenty of misinformation about vaccines for COVID-19 that are in development. Next up: more false information tying COVID-19 to the seasonal flu vaccine.

An April 16 article shared on social media carries the headline "New study: The flu vaccine Is ‘significantly associated’ with an increased risk of coronavirus."

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The article, from a self-described "conscious media" website, mainly cites a 2019 study from the U.S. Armed Forces Health Surveillance Branch that was published in the journal Vaccine in 2020. The study focused on Department of Defense personnel, who have high rates of flu vaccination, and examined whether being vaccinated for a seasonal flu could make someone more or less likely to catch other respiratory viruses.

But the study found no connection between the flu shot and an increased risk of contracting COVID-19.

That’s because the U.S. Armed Forces study’s data was referring to seasonal common coronaviruses in 2017-18, not the new coronavirus that causes COVID-19. (There are seven types of coronaviruses that can infect humans, of which the COVID-19-causing SARS-CoV-2 is one.) This was clarified in the full article, but is ambiguous in the headline.

What’s more, Richard Watanabe, a preventative medicine professor at USC, told PolitiFact that the article doesn’t really provide "strong support for anything they are claiming" since the study found little correlation between the flu vaccine and such viruses. 

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“The CDC says that little 6 month old babies must get SEVEN doses of the Covid vaccine in order to be considered fully ‘up to date’ on their vaccinations.”

Even with regard to coronaviruses that predated SARS-CoV-2, the U.S. Armed Forces study concluded that further research is needed, as "the overall results of the study showed little to no evidence supporting the association of virus interference and influenza vaccination." The study’s data had mixed results for individual respiratory viruses and found that vaccinated individuals were "more likely to have no pathogen detected and reduced risk of influenza when compared to unvaccinated individuals."

The article also leaves out parts of the study that question the data linking coronavirus cases to the influenza vaccine. For instance, the U.S. Armed Forces study referenced a study from 2013 that had similar results except there was "no association between influenza vaccination and RSV, adenovirus, human metapneumovirus, rhinovirus or coronavirus." 

Edward Belongia, an infectious disease epidemiologist who worked on the 2013 study, explained to FactCheck.org that there is little scientific data to support the speculative theory of the flu vaccine increasing the risk of other respiratory viruses.

While this article did specify that the U.S. Armed Forces study was testing common coronaviruses and not COVID-19, the headline was ambiguous and misleading. We rate this headline False.