A resident of Missouri has become the first person in the United States to test positive for bird flu without known exposure to infected animals, according to the Centers for Disease Control and Prevention (CDC) and the Missouri Department of Health and Senior Services. The adult patient, who has underlying health conditions, was hospitalized on August 22, treated with antiviral medications, and has since recovered. The patient's flu type appeared suspicious on an initial test, prompting further testing in state and federal laboratories, which confirmed it was H5, also known as avian flu or bird flu.
The CDC has not identified any transmission to the patient’s close contacts or any other person. Scientists are concerned about the growing number of mammals becoming infected by bird flu, even though cases in humans remain rare. They fear a high rate of transmission could facilitate a mutation of the virus, enabling it to be passed from one human to another.
According to Fortune, the World Health Organization (WHO) commended the national disease surveillance system for identifying the case and emphasized the importance of continued investigations into the patient’s exposure to inform further prevention and response activities.
This is the 14th human case of H5 reported in the United States during 2024 and the first case of H5 without a known occupational exposure to sick or infected animals. The CDC continues to assess the risk to the public as low, but warns that circumstances may change quickly as more information is learned.