A second case of bird flu in a dairy worker has been confirmed in Michigan, state and federal health officials announced Wednesday.
The symptoms were mild and consisted of conjunctivitis. The Texas dairy worker who contracted the virus in March also developed pink eye.
At a press conference on Wednesday, Nirav Shah, deputy director of the US Centers for Disease Control and Prevention, said the finding was “not unexpected” and that it was a scenario “we had prepared for.”
He said that since the discovery of H5N1 in dairy cattle, state and federal health officials have been closely monitoring farmworkers and slaughterhouse workers and urged farmers and farmworker organizations to “be alert, not alarmed.”
Federal officials say they still believe the human health risk from bird flu is low; However, it underlines the need for people who come into contact with infected or potentially infected farm animals or birds to take precautions, including avoiding dead animals and wearing personal protective equipment (PPE) if close contact is necessary.
Although a nasal swab from the person in Michigan tested negative for influenza, an eye swab from the patient was sent to the CDC and tested positive for the influenza A(H5N1) virus.
This is the third case of H5N1 reported in the United States. In 2022, a poultry worker was identified in Colorado.
Although symptoms were mild in the three U.S. farm workers, people elsewhere in the world have suffered more serious illness, including death. According to the World Health Organization, there have been 888 cases of human infection from 23 countries between January 1, 2003 and March 28, 2024; 463 were fatal.
In preparation for a more widespread outbreak, the CDC updated its guidelines for personal protective equipment in dairies and issued a nationwide order for health care providers to be on the lookout for new flu.
On Tuesday, the CDC asked clinical laboratories and health departments to increase the number of flu samples analyzed “to maximize the chance of a case of H5N1 in the community,” Shah said.
The U.S. Department of Agriculture is also expanding its oversight and support by providing $1,500 to uninfected farms to improve biosecurity and $100 to producers who want to purchase inline samplers to test their milk. The agency will also provide $2,000 per farm to cover veterinary costs for testing, as well as shipping costs to send those tests to labs for analysis.
No cases of H5N1 have been detected in California dairy herds.
Officials said ongoing analysis of the national dairy supply indicates it is safe to consume. Despite the risk to human health being low, an official with the Administration for Strategic Preparedness and Response said it will make Tamiflu available upon request “to jurisdictions that are not stockpiling and responding to pre-symptomatic individuals with exposure to confirmed or suspected exposure to infected birds, cattle or other animals.”
Dawn O'Connell, deputy secretary of the preparedness agency, said it has started the “fill and finish” process for approximately 4.8 million doses of vaccine “that closely matches the currently circulating strain of H5N1 through the national pre-pandemic stock of flu vaccines. program.”
She said the decision to move forward with H5N1 vaccines was not in response to any heightened concerns, but since it takes several months to fill and complete the vaccine doses, “the agency thought it made sense given what we saw.”
