Fourth Human Case of Bird Flu Reported, Vaccine on the Way

On July 3, the U.S. Centers for Disease Control and Prevention (CDC) reported the fourth human case associated with an ongoing, multistate outbreak of bird flu in dairy cows this year. This marks the first case in Colorado and follows one case in Texas and two cases in Michigan, as CMM previously reported.

As with the previous cases, the infected individual is a worker on a dairy farm where cows tested positive for the bird flu virus. The person only reported eye symptoms and has since recovered.

The CDC has been watching influenza surveillance systems closely, particularly in affected states, and reported no signs of unusual influenza activity in people.

In May, the CDC recommended farm workers wear personal protective equipment (PPE) to combat bird flu spread, but emphasized that the health risk to the U.S. general public remains low.

Still, last week Reuters reported the U.S. government awarded US$176 million to Moderna to advance bird flu vaccine development for humans. Late-stage testing for humans is expected to begin in 2025 and will focus on safety and immune response. Already, two dozen companies are working to develop a bird flu vaccine for cattle.

As of July 5, the U.S. Department of Agriculture has confirmed 140 cases in 12 states, with Idaho, Colorado, Michigan and Texas reporting the most cases. Since 2020, bird flu has become endemic in bird populations, causing an animal pandemic affecting at least 26 mammal species, according to a previous CMM report. Tests so far indicate that the virus detected in dairy cattle is the same clade that has been affecting wild birds and commercial poultry flocks.