Introduction
BARDA supports advanced development and regulatory approval/clearance for vaccines, therapeutics, and diagnostics to detect, prevent, and treat pandemic influenza infection. In addition, BARDA supports the Nation's vaccine response readiness capabilities through continual development and testing of vaccine candidates against the ever-evolving influenza strains of pandemic potential, including H5N1, as well as sustaining the Nation's vaccine manufacturing capacity.
Since 2017, Highly Pathogenic Avian Influenza (HPAI) Clade 2.3.4.4b A(H5N1) viruses have spread through wild birds, causing wild bird deaths and poultry outbreaks in many countries in Asia, Europe, Africa, North America, and South America. Clade 2.3.4.4b A(H5N1) viruses were originally detected in the U.S. in late 2021 and have been detected in wild birds throughout the country. Spillover to multiple distinct mammalian species has been detected worldwide, including outbreaks in marine mammals (e.g., sea lions, seals, dolphins) and farmed mink in which mammal-to-mammal A(H5N1) virus transmission may have occurred. Most recently, spillover was detected in U.S. dairy cattle in February 2024.
The recent infections with a Clade 2.3.4.4b A(H5N1) virus in one dairy farm worker in Texas (March 2024) and two workers in Michigan (May 2024) have raised concerns about the potential for the virus to spread more broadly in people, necessitating a wholistic public health response. BARDA will leverage existing infrastructures and capabilities to respond to the current HPAI H5N1 threat while continuing to establish new capabilities to improve rapid response to both the current H5N1 virus and other potential pandemic influenza viruses in the future. BARDA's objectives for enabling a successful HHS response to H5N1 are as follows: