NEW YORK (AP) – The U.S. will pay for flu shots for farmworkers this year, a strategy to prevent bird flu from changing into something more dangerous.

Dairy and poultry farms are dealing with outbreaks of bird flu, and 13 workers have picked up infections. All cases are mild and are believed to have spread directly from infected animals to people.

But health officials are worried about what might happen if people are infected with bird flu and seasonal flu at the same time. It’s possible the viruses could swap gene segments, in a process that scientists call reassortment. Bird flu, for example, could gain the ability to spread as easily among people as seasonal flu does.

To prevent coinfections, the Centers for Disease Control and Prevention (CDC) on July 30 said it will spend $5 million to buy seasonal flu shots and get livestock workers vaccinated this fall, working with state and local officials. Another $5 million will be spent to promote the shots.

“We want to do everything we can to reduce the risk that the virus may change,” said the CDC’s Dr. Nirav Shah.

Seasonal flu shots do not protect against bird flu. But they might reduce coinfections, he said. The CDC is also discussing the possibility of offering some farmworkers the antiviral medication Tamiflu to prevent getting the flu, Shah said.

U.S. officials say there are at least 200,000 livestock workers in the country. According to the National Center for Farmworker Health, about a quarter of livestock workers typically get a seasonal flu shot.

Production of a limited amount of bird flu vaccine for people is underway, but the government is not recommending it for farmworkers. There isn’t the kind of person-to-person spread that would trigger that kind of vaccination campaign, Shah said.

A bird flu virus has been spreading since 2020 among mammals – including dogs, cats, skunks, bears and even seals and porpoises – in scores of countries. Earlier this year, the virus known as H5N1 was detected in U.S. livestock.