An unidentified employee of a dairy in northeast Colorado is the fifth person in the U.S. with a confirmed infection of the highly pathogenic avian influenza, but he only had mild symptoms. The person, an adult man who had direct access to infected cattle, developed conjunctivitis, or pink eye, after exposure to infected cows, the Colorado Department of Public Health and Environment said Wednesday. He took an antiviral medication as a precaution and has recovered. State officials haven’t released any other details, including the name of the farm he works at or its location, how the avian flu virus may have hopped from cows to the employee, or whether authorities tested other people who lived or worked with the man. The first person who tested positive for highly pathogenic H5N1 avian flu in the United States was a poultry worker in western Colorado in 2022. The current multi-state outbreak linked to dairy cows infected one dairy worker in Texas and two in Michigan this spring. All four prior cases were mild.