A Colorado inmate is the first person in the United States to test positive for bird flu as an ongoing outbreak in the country continues to affect birds and poultry.
The Centers for Disease Control and Prevention and the Colorado Department of Public Health and Environment said the man, who is under age 40, was involved in culling poultry that were presumed to be infected with the virus.
According to a press release from the CDPHE, the man, an inmate at a state correctional facility in Delta County -- about 100 miles southwest of Aspen -- was exposed while working with infected poultry at a commercial farm in Montrose County, about 50 miles away.
The farm work is part of a pre-release employment program in which inmates can work for private companies and be paid a wage.
Colorado health officials detected the virus in a single nasal specimen from the man and the result was confirmed by the CDC on April 27.
The man was asymptomatic and only reported fatigue for a few days, according to the CDC. He has since recovered but is currently isolating and receiving the antiviral drug tamiflu.
Dr. Rachel Herlihy, state epidemiologist for the CDPHE, told ABC News the man had 10 close contacts who were either coworkers of his on the farm, lived with him or used the same transportation services as he did. They all tested negative.
Repeat testing of the man for influenza was negative.
"We aren’t certain if this individual was truly infected or not and we might actually never know with certainty," Herlihy said. "We don't know if this person was infected, meaning the virus was present and replicating in his body, or if some level of surface contamination of this person's nose may have occurred. You can virus present in your nose, it can be detected on a test, but it doesn't mean it's necessarily causing infection."
The CDC also noted it possible for the detection of bird flu to be the result of surface contamination.
Health officials insisted there is little risk to the general public and there is no evidence the virus spreads from person to person.
"We know that this is really primarily an animal health issue," Herlihy said. "There are lots of viruses that are transmitted within a species but not between species ... Everything we know about the virus right now suggests that it's really just being transmitted between avian species."
According to the U.S Department of Agriculture's latest report, since late 2021, bird flu has been detected in commercial and backyard birds in 29 states and in wild birds in 34 states. More than 2,500 people with direct exposure to infected animals have been tested for bird flu and are negative, the CDC said.
Bird flu infections among people are rare but direct exposure to infected poultry or wild birds increases this risk. The first human case of this specific virus was detected by health officials in the United Kingdom in an asymptomatic patient who had been raising birds that became infected.
Officials say it is safe to eat eggs and poultry, with the USDA always advising proper handling and cooking of poultry products.
Health officials said poultry owners or handlers should monitor fowl for signs of the bird flu and monitor feed and water supplies to avoid contamination.
Herlihy recommended people avoid contact with poultry or birds that appear to be ill or dead as well as contact with surfaces that appear to be contaminated with feces from wild or domestic birds.
Those who are required to handle sick or dead birds are advised to wear gloves and wash their hands with soap and water after.