Bird Flu Infects 3 More Humans, WHO Accelerates Vaccine

Last week, three additional human cases of bird flu were confirmed by the U.S. Centers for Disease Control and Prevention (CDC) in association with a second poultry farm in northeast Colorado. The cases occurred in people who were working directly with infected poultry at a commercial egg layer operation. All three people have mild illness and have been offered the antiviral drug, oseltamivir, for treatment.

This is a different Colorado farm than the one that reported six cases earlier in July. With the addition of these three new confirmed human cases, the total number of human cases associated with poultry outbreaks in Colorado is nine. The CDC has deployed a field team to support Colorado’s response to ongoing poultry outbreaks.

Colorado is a leading state for bird flu infection in poultry. As of July 29, Colorado has reported more than 9.7 million bird flu infected commercial and backyard flocks. All of Colorado’s nine human cases were associated with poultry workers, who were working in depopulation and disposal activities in sick flocks. Additionally, Colorado  is also currently the state with the most recent confirmed cases and the most bird flu-infected dairy herds (50 herds infected since the beginning of the outbreak.) as of July 29, according to the U.S. Department of Agriculture (USDA). In total, the U.S. has confirmed 172 dairy cow herds in 13 U.S. states.

Since April 2024, the total number of confirmed bird flu-infected humans is 13. Prior to this year, only one previous human case of bird flu was reported in the U.S. among a poultry worker in Colorado in April 2022. Still, based on available data, the CDC’s current assessment is that the risk to the public remains low. 

Further, on Monday, the World Health Organization (WHO) said bird flu vaccine developer Sinergium Biotech will share its data with manufacturers in low- and middle-income countries to accelerate a vaccine rollout if a pandemic occurs. The Argentinian manufacturer will lead this effort its candidate bird flu vaccine and aims to establish proof-of-concept in preclinical models.

The WHO said bird flu viruses are a significant public health risk due to their widespread circulation in animals and potential to cause a future pandemic.