For the first time in the United States, a person has tested positive for bird flu, also known as avian flu, without a known history of exposure to infected animals. The Missouri Department of Health and Senior Services and the Centers for Disease Control and Prevention (CDC) confirmed the case on Friday.
The patient, an adult with underlying health conditions, was hospitalized on August 22. Initial tests indicated a flu type that raised suspicion, leading to further testing in state and federal laboratories. These tests confirmed the presence of H5, the strain associated with bird flu. The patient received antiviral medications and, after a period of recovery, was discharged from the hospital.
This case marks the 14th instance of bird flu detection in the U.S. this year, but it is notable for its lack of a direct link to known animal infections. The Missouri health department clarified that while there have been cases of H5 in commercial and backyard flocks, as well as in wild birds, no H5 infections in dairy cattle have been reported in the state.
Previously, all confirmed bird flu cases in the U.S. have involved individuals with direct contact with infected poultry or other animals. The first recorded human case of bird flu in the U.S. occurred in 2022 among farmworkers.
Bird flu primarily affects wild birds and poultry but has recently been detected in mammals, with outbreaks reported in cattle across the country. Human infection generally occurs through close contact with infected birds or contaminated environments.
The CDC has assessed the risk to the general public as low but noted that the situation could evolve as more information becomes available. Historically, while rare instances of bird flu in humans without identified animal sources have been recorded, there has been no evidence of sustained human-to-human transmission, which would significantly elevate the risk level.
As health authorities continue to monitor the situation, they emphasize the importance of vigilance and preparedness in response to evolving threats.
