Chinese scientists have published a paper in the journal Cell Research showing that influenza A virus can aggravate Covid-19 infection in cell and animal tests.
Some experts have warned that the seasonal flu merging with the current Covid-19 pandemic may pose a larger threat to public health. However, the interaction between influenza viruses and the coronavirus remained unclear.
The study by researchers from Wuhan University in central China's Hubei province provides strong experimental evidence concerning the co-infection of the two respiratory viruses.
It reported for the first time that influenza A virus can enhance subsequent Covid-19 infection in cells and mice.
Researchers found that the existing infection of influenza A virus significantly promoted the entry and replication of the coronavirus in a variety of human respiratory tract cells and lung tissue cells, while it also elevated the Covid-19 viral load, leading to more severe lung damage in co-infected mice.
In further experiments, similar promotive effects on Covid-19 infection were not observed with several other respiratory viruses, indicating that influenza A virus has a unique ability to aggravate Covid-19 infection, and thus, the prevention of influenza infection is of great significance during the Covid-19 pandemic, the study noted.
Researchers recommended both influenza vaccination and Covid-19 vaccination to people with a high risk of co-infection.
They also emphasised that the development of novel broad-spectrum antiviral drugs targeting more than one virus is necessary for the treatment of co-infectious diseases.
