Bird flu remains widespread but still a low risk for humans

According to the federal Centers for Disease Control and Prevention in Atlanta, the widespread H5 bird flu remains a low health risk for humans. That assessment comes after a third human case since 2022 was recently reported in the United States, and it was the second involving exposure this year to dairy cows.

While the current public health risk is low, the CDC oversees and works with states to monitor people with animal exposure. The agency uses its flu surveillance systems to monitor for H5N1 activity in people. The CDC influenza (flu) surveillance systems show no indicators of unusual influenza activity in people, including avian influenza A(H5N1).

CDC and state and local health departments monitor people exposed to infected birds, poultry, or other animals for 10 days after exposure. Between February 2022 and now, at least 9,300 people have been monitored for exposure to infected poultry, and since March, another 300 have been exposed to cattle for 10 days. These included:

• At least 325 people tested for novel influenza A after poultry exposure.
• At least 37 people tested for novel influenza A after cattle exposure.

The only human bird flu cases are two cases of exposure to dairy cows in Texas in April and the recent Michigan event. In 2022, a poultry worker in Colorado was infected. All three recovered. However, public health officials continue to remind people that they should not consume raw, unpasteurized milk.

Since early 2022, Bird flu has spread worldwide, including 48 states, affecting 90.8 million in U.S. commercial poultry flocks and 52 dairy herds. The U.S. fatalities included 9,352 wild birds.  Avian flu has also brought down sporadic hundreds of mammals, including opossums, skunks, red foxes, bobcats, mink, and many others.

CDC is the lead agency for human health. The current  H5N1 bird flu situation in wild birds and poultry, dairy cows, and sporadic infections in other mammals falls on USDA’s Animal and Plant Health Inspection Service (APHIS).  The U.S. Department of Interior and USDA are the lead federal departments for outbreak investigation and control in wild birds and agriculture.

CDC’s response to this outbreak of influenza A(H5N1) virus in dairy cattle and other animals largely recently includes:

• Continuing to support states monitoring people exposed to cows, birds, or other domestic or wild animals infected, or potentially infected, with avian influenza A(H5N1) viruses. State or local officials are testing symptomatic people with exposure, and the CDC is conducting confirmatory testing when needed.
• Continuing discussions with multiple states about state-led field investigations to explore key scientific and public health questions related to the ongoing outbreak. CDC coordinates investigation protocols so that data collection can be standardized across states and results can be pooled. CDC’s multilingual and multidisciplinary epidemiological field teams are standing by, ready to deploy to support on-site studies if requested.
• Working to make personal protective equipment (PPE) available for affected farmworkers by asking that jurisdictions use their existing stockpiles for workers on dairy farms, poultry farms, and slaughterhouses, prioritizing the distribution of PPE to affected farms. If needed, HHS/ASPR has indicated it can provide PPE from the strategic national stockpile.
• Continuing work to better characterize the virus from the human case in Texas
• Continuing to engage with manufacturers of commercial diagnostic tests and clinical partners to make progress toward the goal of having an A(H5N1) test that is widely available if needed.
• The process will continue so all states can conduct A(H5) testing on eye specimens using the CDC’s H5 test. 
• Continuing to engage One Health partner organizations from public health, agriculture, wildlife, milk regulatory officials, and others to share information and ensure preparedness to prevent and respond to this emerging infectious disease threat and for any potential human infections.
• Continue monitoring flu surveillance data, especially in areas where A(H5N1) viruses have been detected in dairy cattle or other animals, for any unusual trends in flu-like illness, flu, or conjunctivitis.

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