CDC: Michigan dairy farm worker becomes second human infected with bird flu from cows

The U.S. has documented the second case of bird flu in 2024, the Centers for Disease Control and Prevention announced Wednesday.

Health officials identified the avian influenza case in a Michigan dairy farm worker. This is the second time a case has developed in a person working with dairy cows. The virus appears to have developed under similar circumstances as it did earlier this year for a farm worker at a dairy in Texas.

A nasal swab for the infected person tested negative for influenza, however, an eye swab from the patient tested positive for bird flu, indicating an eye infection, the CDC said in a news release. The infected person in the Texas case also showed only eye symptoms.

Bird flu: WHO's top scientist sounds alarm about bird flu and need for vaccine development

Although the two cases happened in a relatively short period, officials at the CDC said the new case doesn’t change their assessment that the risk to human health remains low.

“However, this development underscores the importance of recommended precautions in people with exposure to infected or potentially infected animals,” the news release said. “People with close or prolonged, unprotected exposures to infected birds or other animals (including livestock), or to environments contaminated by infected birds or other animals, are at greater risk of infection.”

Officials in Michigan said they had initiated “a swift public health response, and we have been tracking this situation closely since influenza A (H5N1) was detected in poultry and dairy herds in Michigan."

"Farmworkers who have been exposed to impacted animals have been asked to report even mild symptoms, and testing for the virus has been made available,” Dr. Natasha Bagdasarian, chief medical executive for the state of Michigan, said in a statement. “The current health risk to the general public remains low. This virus is being closely monitored, and we have not seen signs of sustained human-to-human transmission at this point."

This is a developing story.

This article originally appeared on The Columbus Dispatch: Bird Flu case: CDC says second human infected from U.S. dairy cows