Vaccine Resources: H5N1 Webpage; Annual Influenza Vaccine Composition

H5N1 webpage allows you to easily stay updated on recent outbreaks in animals

In late March 2024, reports emerged of a multistate outbreak of H5N1 avian influenza in dairy cattle. To date, only one person has been infected with this strain of influenza that has shown an ability to spread to mammals. That person had close contact with dairy cattle in Texas. No person-to-person spread has been detected. However, as more cases have been detected in animals, the Centers for Disease Control and Prevention (CDC) and the U.S. Department of Agriculture (USDA) have continued to monitor the situation. Recently, the CDC developed a new webpage so that people can stay abreast of the latest developments.

Check out or bookmark the page.

Annual influenza vaccine composition

In early March 2024, the Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted to remove one of the four strains of influenza from the 2024-2025 influenza vaccines in the U.S. The reason for the move to a trivalent influenza vaccine is because the influenza B/Yamagata lineage is no longer circulating globally. The last time this lineage was detected was in March 2020.

Find out more:

• FDA information
• CDC information
• “What Is Changing in 2024-2025 Influenza Vaccines?” (video) — Dr. Paul Offit, VEC Director and a member of the FDA’s VRBPAC committee, describes the change and why it was made.