Bird flu alert after US victim catches disease from cattle

Fears that the highly pathogenic virus could yet mutate to be passed from human to human

AN individual in Texas has caught bird flu from a cow, raising concerns that the highly pathogenic virus is becoming fitter.

In a health alert on Monday, state health officials said a dairy worker had developed mild conjunctivitis, or “pink eye”, after close contact with a dairy herd. Testing later confirmed that they had caught H5N1, in only the second human case in the United States.

The case adds a “notable” new dimension to an unprecedented outbreak that has already lapped the globe, raising questions about whether the virus is evolving to better infect mammals and people.

“[The] infection in someone with exposure to sick animals is not surprising, but [is] concerning,” said Dr Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health in the US.

Writing on X (formerly Twitter), she added that the case is “notable” as the expanding “geographic and species spread increases concerns about virus’ future potential to infect humans”.

In recent years, H5N1 has killed millions of wild birds and poultry across the globe. But in a string of unexpected developments, it has also jumped to animals including cats, bears, foxes, mink and sea lions. This has raised concerns that the virus could have space to evolve to better infect and spread between mammals – and potentially also humans.

Cows were added to that ever-growing list just last week, when the United States reported H5N1 infections in dairy herds. Since then, cases have been confirmed or are under investigation in five states – Texas, Kansas, Michigan, New Mexico and Idaho.

Although cows can contract other forms of influenza and a study in 2008 found cattle could contract H5N1, this is the first time the virus has actually been found in herds.

While the cows do not become seriously ill, a race is now underway to determine whether they were infected via wild birds – which have been found dead on some farms – or whether the virus has started to spread between herds, which has not yet been proven nor ruled out.

It would be a serious concern if the virus has mutated to spread more easily between cows.

Scientists are also trying to determine how widespread the virus is in cattle, with calls for heightened surveillance in the US.