Bird flu outbreaks in humans may remain rare thanks to this gene

Scientists have identified a gene called BTN3A3 in humans that plays a crucial role in preventing the replication of the avian influenza virus within human cells.

Researchers from the United Kingdom have found that a human gene plays a crucial role in preventing the avian flu from replicating in people.

The study, published Wednesday in Nature, found the gene called BTN3A3 helps prevent the spread of the avian flu among humans, offering a potential reason why many people have never contracted the disease.

“This gene had already been identified before but the discovery of this gene being antiviral against avian flu is a novelty,” Rute Pinto, co-author of the study and a scientist at the Roslin Institute at the University of Edinburgh, told Global News.

“It was a ‘yes moment’… BTN3A3 was inhibiting avian strains but not human strains, that was the first discovery,” she said.

Avian influenza, also known as bird flu, mainly spreads among wild birds such as ducks and gulls and can also infect farmed birds and domestic poultry such as chicken, turkey and quail.

The current outbreak circulating North and South America is known as H5N1 clade 2.3.4.4b. It has killed record numbers of birds and infected mammals such as skunks, minks and sea lions.

Although rare, the virus can sometimes spread from bird to human, as was the recent case in Cambodia, where an 11-year-old girl, who lived near a conservation area, reportedly died from the virus.

To unravel the mystery behind the transmission of viruses from animals to humans, the team of scientists from the MRC-University of Glasgow Centre for Virus Research led a four-year study. They looked at more than 800 human genes and compared them during infection with seasonal viruses or the avian flu.