After U.S. President Donald Trump tested positive for COVID-19 earlier this month, some netizens on social media have linked the president's infection with his flu vaccination history.
They hold the opinion that flu vaccination may make people susceptible to the novel coronavirus, which has turned out to be false.
Influenza is a common and contagious respiratory infection caused by influenza viruses. The flu vaccine fights influenza by activating the human immunity system.
Although COVID-19 also causes respiratory illness with symptoms ranging from mild to severe, it belongs to an entirely different viral family.
In a recent study published in Journal of Clinical and Translational Science, researchers have found that influenza vaccination does not increase one's risks of contracting COVID-19 nor worsen associated morbidity or mortality.
A team of researchers led by Joe Zein, a pulmonologist at Cleveland Clinic, analyzed more than 13,000 patients at Cleveland Clinic between early March and mid-April of this year.
Comparing patients who received a flu vaccine in the fall or winter of 2019 (4,138 patients) against those who did not (9,082 patients), they revealed that flu vaccination is not associated with increased COVID-19 incidence or disease severity, including risk for hospitalization, admission to the intensive care unit or mortality.
"Our findings suggest that we should proceed as usual with our vaccination strategy for global influenza this flu season," Zein said. "Getting the annual flu vaccine remains the best safeguard against the influenza virus, both for yourself and the people around you."