State health officials investigate a detection of H5 influenza virus in a human in Colorado

Person had direct contact with infected poultry; public health experts say the risk to the public is low

The Colorado Department of Public Health and Environment has been monitoring and testing people exposed to poultry and wild birds infected with Highly Pathogenic Avian Influenza, or HPAI, also known as H5N1 flu. A test revealed the presence of the influenza A virus in a single nasal specimen from a person who was working on a farm with infected poultry.

The Centers for Disease Control and Prevention confirmed the result on April 27. Repeat testing on the person was negative for influenza. Because the person was in close contact with infected poultry, the virus may have been present in the person’s nose without causing infection.

The adult male, who is younger than 40, is largely asymptomatic, reporting only fatigue. He is now isolating and receiving the influenza antiviral drug oseltamivir (Tamiflu) per CDC guidance. Scientists believe that the risk to people is low as H5 flu viruses spread among wild birds and poultry. They do not normally infect humans nor spread from person to person. There are currently no known cases of this H5 flu virus spreading among people. There are no other confirmed human cases in Colorado or the United States at this time.

This positive result is due to direct exposure to infected poultry at a commercial farm in Montrose County. The person, who is an inmate at a state correctional facility in Delta County, was working with poultry as part of a pre-release employment program where participants have the opportunity to work for private employers and be paid a prevailing wage. The affected flock has been euthanized and disposed of under the guidance of the USDA and CDA. All members of the response team, including other inmate workers, were provided personal protective equipment while working on the farm.

“We want to reassure Coloradans that the risk to them is low,” said Dr. Rachel Herlihy, state epidemiologist, Colorado Department of Public Health and Environment. “I am grateful for the seamless collaboration between CDC, Department of Corrections, Department of Agriculture, and CDPHE, as we continue to monitor this virus and protect all Coloradans.”

While human infections of the H5 viruses are rare, direct exposure to infected birds increases that risk. Infected birds shed flu viruses in their saliva, mucous, and feces. Public health officials in the United Kingdom confirmed H5N1 virus in January 2022 in a person who was asymptomatic and had direct contact with infected birds.

People should avoid contact with poultry that appear ill or are dead, and avoid contact with surfaces that appear to be contaminated with feces from wild or domestic birds. If you must handle sick or dead poultry, wear gloves and wash your hands with soap and water afterwards. If possible, wear respiratory protection such as a medical facemask and eye protection such as goggles. CDC also has guidance for specific groups of people with exposure to poultry, including poultry workers and people responding to poultry outbreaks. CDC will continue to provide further updates to the situation and update guidance as needed.

It is safe to eat properly handled and cooked poultry and poultry products in the United States. The proper handling and cooking of poultry and eggs to an internal temperature of 165˚F kills bacteria and viruses, including H5N1 viruses.