Co-infection with influenza could suppress replication of SARS-CoV-2A study yesterday in the Journal of Virology suggests that, while co-infection with influenza A and SARS-CoV-2 does not change the trajectory of influenza A, contracting influenza A first could suppress any COVID-19 infection caused by SARS-CoV-2.The study is based on experiments conducted in cultured cells and golden hamsters, and has yet to be replicated in humans.
However, researchers say the findings could have implications for the upcoming cold and flu season, which will bring more co-circulating influenza and COVID-19 viruses."This study could be used as an example of how an immune response to something unrelated can provide protection against SARS-CoV-2," said senior study author Benjamin R.
tenOever, PhD, in a press release from the American Society of Microbiology (ASM), which publishes the journal.In the hamster experiments, animals infected with influenza A virus (IAV) 3 days prior to infection with SARS-CoV-2 generated lower SARS-CoV-2 virus titers than did animals that were infected solely with SARS-CoV-2 at each time point, the authors said.
Time points were days 1, 3, 5, 7, and 14 post-infection.When the experiment was reversed, an initial SARS-CoV-2 infection did not alter the severity of influenza A infection."We find that IAV interferes with SARS-CoV-2 replication in the lung, even more than 1 week after IAV clearance.