Co-infection with respiratory viruses such as the flu and COVID-19 is associated with more severe illness than COVID-19 alone, according to a March 25 study published in The Lancet.
The research team, from the University of Edinburgh in Scotland, said the findings are especially relevant now as public health restrictions are lifted, making respiratory virus co-infections more likely. The team looked at adults with COVID-19 who were admitted to a hospital in the U.K. between Feb. 6, 2020, and Dec. 8, 2021.
1. Overall, researchers identified 583 confirmed co-infections. Of these, 227 patients had influenza viruses, 220 had respiratory syncytial virus and 136 had adenoviruses. Meanwhile, 6,382 had confirmed SARS-CoV-2 mono-infections.
2. Patients with both COVID-19 and flu were more than twice as likely to require mechanical ventilation compared to those with COVID-19 alone.
3. Hospitalized patients co-infected with influenza viruses and adenoviruses also had a higher death risk relative to those with just COVID-19.
4. Researchers said this is the largest study of people with COVID-19 undergoing additional testing for endemic respiratory viruses.
5. They concluded their results offer further support for vaccination against both COVID-19 and influenza viruses, and that "testing for influenza viruses is important in hospital inpatients with COVID-19 to identify patients at risk and a cohort of patients who might have different responses to immunomodulatory and antiviral therapy."