The United States has confirmed the first known human case of H5 bird flu in a person in the western state of Colorado.

The U.S. Centre for Disease Control and Prevention (CDC) said in a statement that the person who tested positive for avian influenza A (H5) virus was involved in the culling of poultry presumed to have had H5N1 bird flu.

The patient reported fatigue for a few days as the only symptom and had since recovered.

According to the CDC, the patient is being isolated and treated with the influenza antiviral drug oseltamivir.

“This case does not change the human risk assessment for the general public, which CDC considers to be low”, the agency said.

CDC has been monitoring  illness among people exposed to H5N1 virus-infected birds since these outbreaks were detected in U.S. wild birds and poultry in late 2021.

To date, H5N1 viruses have been found in U.S. commercial and backyard birds in 29 states and in wild birds in 34 states, according to the CDC.

The agency has tracked the health of more than 2,500 people with exposure to H5N1 virus-infected birds and this is the only human case that has been found to date.