Search called off for baby washed away in Pennsylvania flash flood

A second human case of H5N1 bird flu infection linked to the current outbreak in dairy cows has been detected, in a farm worker who had exposure to infected cows, Michigan state health authorities announced on Wednesday.

In a statement, health officials said the individual had mild symptoms and has recovered. Evidence to date suggests this is a sporadic infection, with no signs of ongoing spread, the statement said.

advertisement

“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,” Natasha Bagdasarian, the state’s chief medical executive, said in the statement.

“The current health risk to the general public remains low,” she added. “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.”

Sign up for Daily Recap

All the health and medical news you need today, in one email

This is only the third human case ever of H5N1 reported in the United States. A man in Texas who worked on a dairy farm was infected there earlier in this outbreak. The country’s first case, in the spring of 2022, was in a man in Colorado who was involved in culling H5N1-infected birds in a poultry outbreak there.

advertisement

To date, nearly 900 people in 24 countries have been confirmed to have been infected with H5N1 since 2003, with most cases tied to exposure to infected poultry. On rare occasions, there have been small clusters of cases that raised questions about whether limited person-to-person spread has occurred — something that is hard to prove when multiple people have the same exposures to infected animals. Ongoing spread among people has not been detected, and it is believed the virus would need to evolve further to gain the ability to spread easily to and among people.

The outbreak in cattle, the first known to have occurred with this virus, was confirmed in late March, though evidence suggests that it had been underway for several months before testing revealed the cause of a drop in milk production among cows.

Since then the U.S. Department of Agriculture has confirmed outbreaks in 51 herds in nine states, including Michigan, which has reported 19 infected herds — more than any other state. (The USDA’s most recent tally does not include four that Michigan reported since May 17.) Experts following the outbreak believe the national count of affected herds significantly underestimates the scope of the problem. Both the USDA and the Centers for Disease Control and Prevention have admitted that farmers have been reluctant to allow testing of their cows or their workers, afraid of the stigma attached to being associated with the outbreak.

But that has been less true in Michigan, where state officials have taken a uniquely aggressive stance in its public health response, informed, in part, by the devastating impacts H5N1 has had on the state’s poultry flocks in the past few years.

On May 1, Tim Boring, director of the state’s Department of Agriculture, declared an “extraordinary animal health emergency,” signing an order requiring Michigan farmers to step up their biosecurity measures. “Most farms have been good cooperators with that,” Boring told STAT in an interview last week.

Related: When should we start making H5N1 vaccine, and who will make that decision? In short, it’s complicated

He said “well over several dozen individuals,” including some who had been experiencing flu-like symptoms, have been tested for H5N1. This case is the first to have come back positive.

Farmers have also been open to working with local health authorities to fill out questionnaires that could help investigators track how the virus is moving between dairy herds throughout the state. “Hundreds and hundreds of farm workers here in Michigan have been interviewed,” Boring said. “They understand the importance of understanding how this is moving around so we can limit the spread of this.”