A dairy worker in Texas has tested positive for avian flu (H5N1), representing only the second human case in the US.
H5N1, commonly known as bird flu, has been spreading rapidly across cattle in the American South and Midwest over the past few weeks but has so far largely failed to make the jump to humans.
Bird flu is caused by an influenza virus which is generally observed among wild aquatic birds, infect domestic poultry, animals and humans.
One other person tested positive in Colorado in April 2022 after direct contact with poultry.
Across the globe, a total of 887 humans have been infected with avian flu since 2003, according to the World Health Organization, with 462 resulting in death.
However, the Texas Department of State Health Services (DSHS) said on Monday that the person infected last week was suffering only mild symptoms, and was being treated with the antiviral drug oseltamivir.
Texas, Idaho, Michigan, Ohio, and New Mexico have all recorded bird flu infections in cows, raising fears that the virus's widespread replication will make it easier to spread to humans.
However, federal agencies stated that they had not yet detected any mutations in the virus that would make it more transmissible for humans, concluding that the overall risk to the public remains low.
They added that there was no danger of milk being infected with the disease because it is pasteurized before being sold to humans.
Scientists have long feared that bird flu could be the source of a future human pandemic, due to the very large pool of infected animals in which it can continuously mutate.
It first began to infect humans during an outbreak among chickens in Hong Kong in 1997 and has periodically gone epidemic since.
The current outbreak, which began in 2020, has been particularly severe, afflicting wild and captive bird populations on multiple continents as well as killing seven humans.
