A person in Missouri has become the United States' first case of H5 avian influenza without a known exposure to a sick animal, as reported by the U.S. Centers for Disease Control and Prevention (CDC) on Friday. This case marks the 14th human instance of H5 avian flu reported in the U.S. during 2024 and is notable for being the first without known occupational exposure to sick or infected animals.

It is also the first H5 case detected through the country's national flu surveillance system rather than through targeted surveillance related to the ongoing bird flu outbreak in animals. The Missouri Department of Health and Senior Services (MDHSS) is currently investigating this case. The individual, who had underlying medical conditions, was hospitalized on August 22. They tested positive for influenza A, received treatment with influenza antiviral medications, and have since recovered and returned home, according to the MDHSS.

While there are no cases of bird flu among cattle in Missouri, the state has experienced outbreaks of the virus among poultry. Despite these occurrences, the CDC maintains that the risk assessment of H5N1 for the general public remains low. The agency continues to monitor the situation closely to ensure the public's health and safety.