A hospitalized patient in Missouri was infected with bird flu despite having had no known contact with dairy cows or other animals associated with an ongoing outbreak, health officials said Friday.
This is the 14th person in the U.S. sickened with bird flu since March, when the virus was detected in cows, after infecting wild birds and mammals worldwide. One other person was infected in 2022.
However, the U.S. Centers for Disease Control and Prevention said in a statement that it was the first of those 14 "without a known occupational exposure to sick or infected animals."
The risk to the general public remains low, the CDC said. No unusual flu activity has been detected in the U.S., including in Missouri, officials said.
The latest case was confirmed after the person, an adult, was hospitalized on Aug. 22 with other medical conditions, officials with the Missouri Department of Health and Senior Services said in a statement.
The person tested positive for influenza A, and CDC officials later confirmed it to be bird flu. The person received antiviral medication and has since recovered and gone home, health officials said.
It's not clear whether the hospitalization was caused by the bird flu infection or the person's existing health conditions, said Lisa Cox, a spokesperson for the Missouri health department.
Health officials didn't release the person's name, age or hometown. No close contacts of the person have been infected, CDC officials said.
The case raises questions about how the person was exposed to the virus. All the previous U.S. infections were among people who worked around cows and poultry.
Bird flu has been detected in nearly 200 dairy herds in 14 states so far this year, but not in Missouri, according to the U.S. Department of Agriculture. Bird flu has also been found in commercial and backyard flocks and in wild birds. The person did not report drinking raw milk, which can contain live virus, Cox said.
The investigation is continuing, officials said.
It's the first case detected through routine influenza surveillance rather than through targeted efforts to identify people infected with bird flu through exposure to infected cows and poultry, officials said.