The case comes amid concerns that an ongoing outbreak among US birds could lead to more human infections.
The first known human case of H5N1 bird flu in the United States it has been detected in one person in Colorado, according to the Centers for Disease Control and Prevention (CDC).
The person tested positive after being involved in the culling of poultry suspected of having H5N1 bird flu, the CDC said in a statement. The infection comes amid a broader outbreak of the particular strain of bird flu in the United States.
The agency said the case was only the second human infection globally with the specific group of H5 viruses, with the first detected in the UK.
“This case does not change the assessment of human risk to the general public, which the CDC considers to be low,” the agency said.
The agency began monitoring people believed to be exposed to the virus in 2021. It has been detected in commercial and backyard birds in 29 US states and in wild birds in 34 states.
The outbreak has caused sacrifice of millions of chickens and turkeys in the United States.
Health experts have raised concerns that the continued spread of the virus could lead to mutations that spread more easily to humans.
The infected patient reported fatigue for a few days as the only symptom and has since recovered, the CDC said, adding that the person was being isolated and treated with the flu antiviral drug oseltamivir.
“The CDC has tracked the health of more than 2,500 people exposed to birds infected with the H5N1 virus and this is the only case found to date. Other individuals involved in the slaughter operation in Colorado have tested negative for H5 virus infection, but are being retested out of an abundance of caution,” the CDC said.