A new study has just reported an alarming trend that pet cats may inadvertently harbor the highly pathogenic bird flu virus, H5N1, that has ravaged poultry farms across the United States for more than two years. 

The virus is not highly contagious among humans, but scientists have warned that a couple of mutations in cats could be the reason it could leap to people and then potentially become a much greater public health problem.

The research, published in the Taylor and Francis journal, comes after a worrying incident in South Dakota earlier this year. Ten cats from a single residence were found dead in April, prompting scientists to investigate. The animals had exhibited respiratory and neurological distress symptoms, but further testing showed that the animals were infected with a strain of H5N1 closely matching a version seen on a dairy farm some 80 kilometers away. Bird feathers near the cats suggest they may have consumed infected wild birds that carried the virus from the farm.

Unlike many animals, cats contain two types of receptors that make it possible for both bird flu and seasonal flu viruses to attach. This makes cats some of the best candidates in which to study co-infection. Scientists are frightened that during flu season if a cat is infected by both H5N1 and a human seasonal flu virus, the two may recombine, creating a mutated strain that transmits more easily to humans.

“Infected cats develop systemic infections and shed the virus through both respiratory and digestive tracts, potentially creating multiple routes of exposure to humans,” the study noted. It added, “The ability of the virus to persist and adapt in mammalian hosts heightens the risk of evolving into strains with increased transmissibility, posing an emerging zoonotic threat with profound public health implications.”

An author of the study, Dr Suresh Kuchipudi cautioned more surveillance warning that a broad problem is being overlooked since the focus has been put to be in relation to dairy farms and food safety.

“In the process of addressing the immediate problem which is dairy farms and the milk as a food safety problem, and then human surveillance – we might be missing a much bigger, evolving story. It may already have been happening in plain sight,” he said.

Though so far, there is no indication that cats have passed H5N1 to humans, the scientists say that the need for monitoring is urgent and not a time to wait for things to get worse. The findings resonate with other recent warnings, like those from the Scripps Research Institute in California, which indicated that bird flu viruses were mutating faster than ever before. This has raised concerns over the possibility of a pandemic in the future.

With flu season underway and the virus’s ability to mutate, keeping a close watch on cats and their interactions with infected birds or animals is crucial, researchers say.