A team of British researchers has made progress in studying a human gene that can prevent most bird flu viruses from infecting humans, Reuters and Agerpres reported on Wednesday.

Bird flu is mainly spread among wild birds such as ducks and seagulls, but can also infect domestic and domestic birds such as chickens, turkeys and quail. Although these viruses primarily affect birds, they can also be transmitted to birds of prey and, in rare cases, to humans, usually through close contact with infected individuals.

A team of scientists from MRC University’s Virus Research Center in Glasgow studied hundreds of genes normally expressed by human cells, comparing their behavior when infected with seasonal human or avian influenza viruses.

They focused on a gene called BTN3A3, which is expressed in both the upper and lower respiratory tracts of humans. This gene, which the researchers called “Force B”, was found to block the replication of most strains of bird flu in human cells.

However, the antiviral activity of the gene did not protect against seasonal human influenza viruses.

The discovery could prevent a bird flu pandemic in humans

The gene is part of a larger defense apparatus in the human immune arsenal against avian viruses. All major human influenza epidemics, including the 1918–1919 global influenza pandemic, were caused by BTN3A3-resistant influenza viruses.

Thus, the gene is a critical factor in the bird flu strain’s potential to cause a pandemic in humans, the researchers say. Of course, viruses mutate all the time, and that doesn’t mean that bird flu viruses couldn’t have evolved to avoid the BTN3A3 gene.

Earlier this year, a new strain of H5N1 bird flu, which is easily transmitted among wild birds, exploded around the world, infecting and killing a variety of mammal species and raising fears of a human pandemic.

According to the World Health Organization (WHO), only a few cases of human disease have been registered to date.

About 50% of H5N1 strains circulating worldwide by 2023 are resistant to BTN3A3, said Professor Massimo Palmarini, one of the authors of the study published in the scientific journal Nature.

“These are the types of high-risk things that we should be paying close attention to,” said Sam Wilson, one of the study’s lead authors.