Wednesday, Jul. 3, 2024
Is Pfizer working on a vaccine for the bird flu?
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.
This fact brief is responsive to conversations such as this one.
Sources
- Pfizer Pfizer Reiterates Commitment to Pandemic Preparedness
- Centers for Disease Control Highly Pathogenic Avian Influenza A (H5N1) Virus Infection Reported in a Person in the U.S.
- Centers for Disease Control A(H5N1) Bird Flu Response Update
- Centers for Disease Control CDC Reports Second Human Case of H5 Bird Flu Tied to Dairy Cow Outbreak
- Colorado Department of Agriculture USDA Confirms Detection of Avian Influenza in Dairy Cattle in Colorado
- Centers for Disease Control Technical Report: Highly Pathogenic Avian Influenza A(H5N1) Viruses
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Fact briefs are bite-sized, well-sourced explanations that offer clear "yes" or "no" answers to questions, confusions, and unsupported claims circulating online. They rely on publicly available data and documents, often from the original source. Fact briefs are written and published by Gigafact contributor publications.
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