2nd human case of bird flu confirmed in Michigan: Health officials

A second person in the United States has been infected with bird flu, health officials said Wednesday.

The case was identified in a Michigan farmworker who had regular exposure to livestock-infected bird flu, or avian influenza, the Michigan Department of Health and Human Services (MDHHS) said.

The Centers for Disease Control and Prevention (CDC) said the Michigan dairy worker was being monitored because of their work exposure to infected cattle and reported symptoms to local health officials. A nasal specimen tested negative for influenza virus at the state health department laboratory while an eye specimen was sent to CDC for testing, which confirmed bird flu infection.

MDHHS said the farm worker has since recovered and it will not be releasing any additional identifying information about the farmworker.

It comes after the first human case of bird flu was identified in Texas last month and also linked to cattle. The infected individual worked directly with sick cattle and reported eye redness as their only symptom. Only three cases, including the Michigan case, have ever been reported in the U.S.

The risk to the general public remains low, according to MDHHS and the CDC.

"Michigan has led 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," Dr. Natasha Bagdasarian, chief medical executive at MDHHS said in a statement. "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."

"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 exactly how public health is meant to work, in early detection and monitoring of new and emerging illnesses," the statement continued,"

MDHHS said it is working with the Michigan Department of Agriculture and Rural Development (MDARD) to monitor the health of people exposed to infected animals and monitoring impacted poultry.

In early March, the U.S. Department of Agriculture announced a bird flu strain that had sickened millions of birds across the U.S. was identified in several mammals this year.

At the time, three states had reported cases of bird flu in mammals in 2024, including striped skunks found in Washington state, a mountain lion in Montana and a raccoon in Kentucky.

A few weeks later, federal and state public health officials said they were investigating an illness among primarily older dairy cows in Kansas, New Mexico and Texas and causing symptoms including decreased lactation and low appetite.

The USDA said in a statement at the time that "there is no concern about the safety of the commercial milk supply or that this circumstance poses a risk to consumer health."

Several dairy cows have been infected, resulting in milk samples showing inactive remnants of the virus, but health officials say the food supply is safe.

MDHHS said it recommends seasonal flu vaccination for people working on poultry or dairy farms.

"It will not prevent infection with avian influenza viruses, but it can reduce the risk of coinfection with avian and flu viruses," the press release said.

In a meeting with public health partners on Tuesday, CDC Principal Deputy Director Nirav D. Shah said avian influenza surveillance systems in the U.S. must continue "operating at enhanced levels during the summer" and to increase the number of samples positive for influenza A virus submitted to make sure even rare case can be detected.

ABC News' Youri Benadjaoud and Sony Salzman contributed to this report.