3 Colorado poultry workers catch presumed bird flu as U.S. cases creep upward

Three poultry workers in northeast Colorado are presumed to have fallen ill with bird flu as more human cases sprout across the U.S., state and federal health officials said Friday.

The three workers were working to depopulate chickens at an egg-laying facility experiencing an outbreak of H5N1 avian influenza, which has been circulating in wild birds and has caused multi-state outbreaks in dairy cows, the Centers for Disease Control and Prevention said.

Colorado epidemiologists suspected the poultry workers’ infections to be a result of working directly with infected poultry, the state Department of Public Health and Environment said.

The workers have exhibited mild symptoms that include conjunctivitis, or pink eye, and common respiratory infection symptoms, state officials said. None of the workers were hospitalized.

Before Friday, four people, all dairy workers, had fallen ill with bird flu this year, with one case in Texas, two cases in Michigan and a fourth case in northeast Colorado, identified in early July. With the three Colorado workers, there are now seven cases of bird flu in the U.S. The three cases are the first to happen at the same place.

Officials have been worried about the spillover of avian influenza to humans. Initially the influenza was believed to have come from wild birds before spreading to chickens and cows. The CDC says risk remains low to the public.

There are no signs of unexpected increases in flu activity in Colorado, or in other states affected by bird flu. But the latest cases are concerning because of the potential to cause severe disease, the CDC said.

“The other reason these types of human infections are concerning is because of their pandemic potential,” the CDC said. “If these viruses were to change to spread easily from person-to-person, it could trigger a pandemic.”

The latest Colorado workers have had specimens collected and sent to the CDC to confirm testing for the specific H5N1 virus currently circulating. Colorado public health officials have collected additional samples from symptomatic workers that are being tested this weekend, officials said.

In 2022, an incarcerated Colorado man was the first person in the U.S. to get bird flu. He was working on a poultry farm.

State health officials say it is still safe to eat properly handled and cooked poultry products. Doing so kills bacteria and viruses, including bird flu viruses.

To date, 48 states have bird flu outbreaks in poultry, the CDC said. A dozen states have outbreaks among dairy cows.

This article originally appeared on USA TODAY: 3 Colorado poultry workers fall ill, CDC to test for bird flu