Bird flu could 'potentially infect' cows if given the chance - virus expert
Scientists have discovered that some bird flu variants 'are more able to infect cow cells and tissues" than older variants.
The H5N1 avian influenza virus – commonly known as bird flu – has been causing outbreaks in dairy cows in the United States since March 2024.
A new study published in Nature Communications and led by scientists at the MRC–University of Glasgow Centre for Virus Research, examined a large panel of viruses.
According to Professor Massimo Palmarini, from both the Erasmus Medical Centre and the MRC–University of Glasgow Centre for Virus Research, the results identify that different bird flu viruses "have very different abilities".
"While the strain currently spreading in US cattle is clearly the best adapted so far, there are other bird viruses that could potentially infect cows if given the chance," he said.
Researchers also warned that their findings highlight the urgent need for continued testing and monitoring, especially as the virus continues to spread in dairy cattle and remains a potential pandemic threat.
Bird flu
The discovery of H5N1 in cows in spring 2024 was a major surprise, as flu viruses were not previously thought to cause outbreaks in cattle.
However, H5N1 is known for its ability to spillover in mammals, raising concerns that it could spread further into other species.
The latest study also showed that the ability of H5N1 viruses to infect cow cells and mammary depends on changes that viruses have acquired over time.
Researchers found that bird flu viruses vary widely in how well they can replicate in cow cells. This means some bird viruses may already be closer than others to being able to infect cattle and potentially other mammals.
Professor Pablo Murcia, from the MRC–University of Glasgow Centre for Virus Research, said: “Influenza viruses are constantly changing, and this rapid evolution allows them to infect new animal species.
“The better adapted they become to infect mammals, the more chances they have to infect and adapt to humans – as we saw with the 2009 swine flu pandemic.”
The study, ‘The potential of H5N1 viruses to adapt to bovine cells varies throughout evolution’ is published in Nature Communications.
The work was funded by UKRI Medical Research Council (MRC), Wellcome and the UKRI Biotechnology and Biological Sciences Research Council (BBSRC).
