A new research paper published in Lancet found that having flu and Covid-19 at the same time more than doubles the risk of a patient dying.
Scientists also discovered that individuals who had contracted both Sars-CoV-2, the virus that causes Covid-19, and influenza viruses were more than four times more likely to require ventilation support and 2.4 times more likely to die than if they just had Covid-19.
“We found that the combination of Covid-19 and flu viruses is particularly dangerous,” said Professor Kenneth Baillie of Edinburgh University. “We expect that Covid-19 will circulate with flu, increasing the chance of co-infections. That is why we should change our testing strategy for Covid-19 patients in hospital and test for flu much more widely.”
The study looked at more than 305,000 hospitalised patients with Covid-19 and involved researchers from Edinburgh University, Liverpool University, Imperial College London and Leiden University in the Netherlands.
A total of 6,965 patients were found to have had Covid-19, while 227 also had the influenza virus. These individuals experienced significantly more severe outcomes, researchers found.
“We were surprised that the risk of death more than doubled when people were infected by both flu and Covid-19 viruses,” said Professor Calum Semple of Liverpool University. “It is now very important that people get fully vaccinated and boosted against both viruses, and not leave it until it is too late.”