H5 Bird Flu

H5 bird flu is a viral disease that primarily infects poultry (e.g., chickens, turkey, ducks) and other wild birds. H5 bird flu is particularly contagious in bird populations and has resulted in the deaths of millions of birds in the United States. There have been 66 positive cases of H5 bird flu reported in humans in the United States since April 2024. No person-to-person spread of H5 bird flu has been detected. 

H5 bird flu symptoms are similar to the seasonal influenza virus. Possible symptoms include fever, cough, sore throat, muscle aches, nausea, abdominal pain, vomiting, diarrhea, eye infections, difficulty breathing, pneumonia, and severe respiratory disease. If you have had close and/or sustained unprotected contact with infected birds or animals or their contaminated environments, monitor for these symptoms for 10 days after your last exposure. If you have these symptoms, speak with your healthcare provider about the length of your at-home isolation before returning to your normal activities. The same diagnostic tools that are used to detect seasonal influenza viruses like the flu can also detect H5 bird flu.

Updated on January 7, 2025 

H5 bird flu spreads to humans when enough virus gets into a person’s eyes, nose, or mouth or is inhaled from an infected bird or animal. There is no evidence of sustained person-to-person spread of H5 bird flu.

While the risk of H5 bird flu is low, everyone should take the following precautions:

• Avoid contact with poultry, wild birds, and other animals that appear ill or are dead, as well as contact with surfaces that may have been contaminated with their feces.
• Avoid uncooked or undercooked poultry, meat, and eggs.
• Drink pasteurized milk that has been treated to kill harmful bacteria. 
• Cook poultry, meat, and eggs to the right internal temperature to kill bacteria and viruses, including H5 viruses.
• Wash your hands and surfaces thoroughly before and after handling poultry, meat, and eggs.

People with close and/or sustained unprotected contact with infected birds or animals or their contaminated environments are at a greater risk of infection. To reduce the spread, those with known exposure to H5 virus-infected birds or other animals should isolate themselves away from others and seek medical attention if symptoms worsen. People who work with or have recreational exposures to infected animal populations, maintain backyard birds/poultry, and engage in hunting should consider taking these additional protections:

• Avoid contact with poultry, wild birds, and other animals that appear ill or are dead, as well as contact with surfaces that may have been contaminated with their feces.
• Wear personal protective equipment (PPE): 
  • Disposable outer garments with long sleeves and a sealed apron
  • Disposable gloves or heavier work gloves that can be disinfected
  • Properly-fitted high filtration masks such as N95s, KN95s, and KF94s
  • Safety goggles and disposable head coverings
  • Disposable shoe covers or boots that can be cleaned and disinfected. 
• Wash hands thoroughly with soap and water or an alcohol-based hand rub after contact with birds and mammals.
• Avoid touching your skin with gloved hands.

Added October 10, 2024 

On April 24, the Food and Drug Administration (FDA) announced that traces of H5N1 bird flu had been detected in about 20 percent of milk samples from U.S. grocery stores, and reemphasized that the commercial milk supply of pasteurized milk is still safe for consumption.

The pasteurization process inactivates harmful bacteria and viruses, which means that the found traces of H5 bird flu are not live or infectious virus. Many studies have shown that pasteurization is effective at inactivating similar influenza viruses.

According to experts, finding traces of the virus in this percentage indicates that the H5 bird flu outbreak in cows is larger than originally thought. USDA has announced mandatory testing for bird flu for any dairy cows moving across state lines. Only milk from healthy animals is authorized to be sold, and pasteurization is required for any milk entering interstate commerce.

FDA will continue to monitor the milk supply and has cautioned against the consumption of raw or unpasteurized milk or milk products.

Additionally, to keep the beef supply safe, the U.S. Department of Agriculture (USDA) has conducted testing of ground beef samples from retail outlets in states where cows have tested positive for the virus. To date, no H5 virus has been found in any of the tested samples. Testing will continue and only meat that has passed USDA inspection can be sold in U.S. stores and restaurants.

Note: When communicating with the public about the H5 bird flu outbreak and the safety of the milk and beef supplies, public health officials should emphasize that their information is based on what is known to date, and that health guidance could change as more information becomes available. Continued monitoring for any further circulation of the virus by federal, state, and local officials is critical to protecting the public’s health.

Updated October 10, 2024