Highly Pathogenic Avian Influenza A(H5N1) Virus: Recommendations for Human Health Investigations and Response

A person has tested positive for avian influenza A(H5) virus (H5 bird flu) in the U.S., as confirmed by the Centers for Disease Control and Prevention (CDC) and reported by the Colorado Department of Public Health and Environment on April 28, 2022. This case occurred in a person who had direct exposure to poultry and who was involved in the culling (depopulating) of poultry with presumptive H5N1 bird flu. Starting in January, the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) detected highly pathogenic avian influenza (HPAI) A(H5N1) virus in wild birds in the United States followed by multiple detections in U.S. commercial poultry and backyard bird flocks [1,2]. Detection of A(H5) virus in one person who was involved in culling of poultry does not change the human health risk assessment, which remains low for the general public. People with work or recreational exposures to infected birds are at greater risk of infection and should follow recommended precautions. The purpose of this HAN Health Advisory is to notify public health workers, clinicians, and the public of the potential for human infection with this virus and to describe the CDC’s recommendations for patient investigation and testing, infection control including the use of personal protective equipment, and antiviral treatment and prophylaxis.