Yes.
Pfizer has been working on a vaccine for the H5N1 influenza virus since 2023 as part of the company’s “broader pandemic preparedness efforts.” The company said May 28 that a vaccine candidate has shown to provide “notable increases in antibody responses” against the virus commonly called bird flu.
Transmission to humans has been rare in the United States but it occurred in a single case in 2022 in Colorado and twice in the past two months in Texas and Michigan. Last month, dairy workers were monitored for the disease after bird flu was detected in dairy cows in northeastern Colorado.
Between 2022 and June 4, 2024, at least 29 people contracted bird flu in nine countries. Seven died, 15 became severely ill, six had mild symptoms and eight were asymptomatic. The CDC said the human health risk from the disease remains low.
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