Unpacking the current threat landscape
Avian influenza (HPAI) A(H5N1), commonly known as bird flu, has had an increase in human cases in the United States recently, particularly among poultry and dairy workers. H5N1 has primarily circulated in the Midwest, with these cases raising concerns about potential human transmission and broader public health implications. Understanding the current landscape of H5N1, including recent data and prevention strategies, is essential as health officials monitor the situation.
The CDC is monitoring influenza data at national, state, and local levels. As of October 9, 2024, 18 human cases of H5N1 have been reported in the US since 2022. Since February 2022, more than 15,500 individuals have been monitored after exposure to infected animals, with 590 tested for novel influenza A. Recently, approximately 6100 individuals have been monitored, including 3350 exposed to dairy cows and 2800 to birds and other animals.1
Currently, CDC surveillance systems indicate no unusual flu activity related to H5N1. In the week ending October 19, 2024, public health laboratories reported no positive tests for novel influenza A, and wastewater monitoring detected H5 at only 1 out of 320 sites.1
CDC continues to collaborate with the USDA, FDA, and state health officials using the One Health approach to monitor the situation. The agency has deployed a multilingual epidemiological field team to assist local health departments with outreach and surveillance efforts. To date, more than 5100 individuals exposed to potentially infected animals have been monitored, and more than 54,000 specimens have been tested for H5N1viruses.2