Bird flu detected in Missouri where patient had no contact with animals prior to getting sick

A case of bird flu has been detected in a Missouri patient, the first human bird flu case in the state and the first nationwide in someone who reported no exposure to animals before getting sick. 

The patient, who has underlying health conditions, was hospitalized on Aug. 22. Testing at the hospital confirmed that they had bird flu, the Missouri Department of Health and Senior Services said in a release Friday.

The case marks the 14th case of bird flu detected in humans in the U.S. this year and is the first instance where a person contracted bird flu without any prior exposure to animals, the Centers for Disease Control and Prevention said Friday.

The CDC has not found any transmission of the bird flu from the Missouri patient to close contacts or others, and says that, while rare, some bird flu cases do not have an identifiable animal origin.

“The results of this investigation will be particularly important in light of the current lack of an obvious animal exposure. It is important to note that, while rare, there have been novel influenza A cases where an animal source cannot be identified,” the CDC wrote Friday.

The other 13 cases of bird flu in people in the U.S. in 2024 consist of 10 patients in Colorado, two in Michigan and one in Texas. Of those, the CDC says four patients had been exposed to cattle and nine had been exposed to poultry.

Since Feb. 8, 2022, there have been 617,239 birds in Missouri infected by bird flu, with the last detection happening in February 2024. The outbreak there impacted 13 commercial flocks of poultry and 16 backyard flocks according to the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service.

Wild birds in Missouri have also been known to contract bird flu, the CDC said. There have not yet been any herds of livestock infected with bird flu in Missouri, according to APHIS data.