JEFFERSON CITY, MO. — The Centers for Disease Control and Prevention (CDC) confirmed on Sept. 6 that a human case of H5 avian influenza A, also known as highly pathogenic avian influenza (HPAI), was detected by the Missouri Department of Health and Senior Services (DHSS). 

According to information from health officials, this person did not report exposure to animals, which is a first for tracking the virus in humans. In 2024, 14 people have been recorded with H5 bird flu cases, and those cases were linked to exposure to poultry or dairy cattle. 

“Nationally, this is the first case of H5 that has been detected as part of the flu surveillance system, rather than the targeted H5-outbreak specific surveillance that has been conducted as part of ongoing animal outbreaks which has identified all the other cases,” DHSS said in its statement. 

On Aug. 22, the Missouri State Public Health Laboratory was sent a specimen from a patient in the hospital. Information from health officials said the adult patient had underlying medical conditions and tested positive for influenza A. The patient recovered and was discharged.

The agency explained transmission or risk of infection for the public remains low for H5 bird flu.

DHSS added that no H5 infection in dairy cattle has been reported in Missouri, with only some H5 cases in commercial or backyard flocks and wild birds.

The Missouri State Public Health Laboratory conducted additional testing to determine the influenza subtype as part of a typical influenza surveillance testing program. The testing resulted in a presumptive detection of the H5 subtype, with the specimen forwarded to the CDC for additional testing and confirmation.

As DHSS continues to monitor the situation, it added that there’s “no sign of unusual influenza activity in people, including no increase in emergency room visits for influenza and no increase in laboratory detection of human influenza cases in Missouri.”  

USDA data from last week confirmed 197 cases of HPAI in dairy cattle since the outbreak began earlier this year, affecting herds in 14 states: Texas, Kansas, Michigan, Ohio, North Carolina, Minnesota, Iowa, Oklahoma, South Dakota, New Mexico, Colorado, Wyoming, Idaho and California.

CDC recently published its findings about human HPAI cases in Colorado earlier in the summer.