Coronavirus: co-infection with influenza can speed up replication of pathogen that causes Covid-19, study says
- Modifications to the structure of human cells caused by a flu bug can make it easier for the coronavirus to invade them, Chinese researchers say
- Upcoming flu season presents a ‘potentially severe threat to public health’, they say
Laboratory experiments showed that the influenza A virus could modify the structure of a wide variety of human cells within hours of infection. The SARS-CoV-2 virus could then make use of those changes to invade the cells more easily and reproduce more efficiently, according to a paper posted on the preprint website Biorxiv.org – which means it has not been peer-reviewed – on Wednesday.
“The upcoming flu season in the northern hemisphere merging with the Covid-19 pandemic presents a potentially severe threat to public health,” said the team led by professor Xu Ke from the State Key Laboratory of Virology at Wuhan University.
In China, people have been urged to have flu shots before the end of October. Flu and Covid-19 share some symptoms that health authorities fear could not only complicate diagnosis but generate panic.
But flu shots are in short supply, forcing some people to turn to untested and overpriced alternatives on the black market, according to some mainland media reports.
Xu’s team conducted their tests on a range of human cells from different parts of the body. Besides the influenza A virus, they also included other pathogens such as rhinovirus, Sendai virus and enterovirus in the experiment.
After exposing cells pre-infected by those viruses to the new coronavirus, the researchers found only the influenza A virus could make the infection worse.