A new study has found that getting a flu shot can reduce the risk of contracting a SARS-CoV-2 infection. The study, published in the American Journal of Infection Control by scientists at the University of Michigan, also found that individuals who received a flu shot were less likely to experience severe cases of Covid-19. The team, led by Dr. Anna Conlon, analyzed health data from 27,000 people who tested positive for SARS-CoV-2 until July 15, 2020. Of those, 13,000 had received a flu shot in the previous 12 months. The study found that individuals who received a flu shot were 24% less likely to test positive for Covid-19.
Furthermore, those who did not receive a flu shot and contracted Covid-19 were one-third more likely to require hospitalization and twice as likely to require ventilation. The length of hospital stay was also significantly longer for this group. The study’s findings are surprising because individuals who received a flu shot are typically more likely to be in a high-risk group. The scientists attribute the protective effect of the flu shot to the activation of the immune system. The flu shot’s learned immune response against the flu virus would put the immune system on alert and provide partial protection against the new coronavirus.
While the study did not investigate whether the flu shot reduces mortality rates, the scientists believe that the “trained immune response” effect likely occurs with other vaccines. The flu shot’s annual renewal makes it easier to detect the trained immunity effect. The study’s findings suggest that getting a flu shot can provide additional protection against Covid-19 and reduce the severity of the disease.
