Prevention and Antiviral Treatment of Avian Influenza A Viruses in People

The best prevention is to avoid sources of exposure

The best way to prevent H5N1 bird flu is to avoid sources of exposure whenever possible. Infected birds shed avian influenza A viruses in their saliva, mucous, and feces and other infected animals may shed avian influenza A viruses in respiratory secretions and other body fluids (e.g., cow milk). Avian influenza A viruses also can infect the respiratory tract of mammals and cause infection in other organ tissues. People rarely get avian influenza A virus infection; however, human infections with avian influenza viruses can happen when enough virus gets into a person's eyes, nose or mouth, or is inhaled. This can happen when virus is in the air (in droplets or possibly dust) and a person breathes it in, or when a person touches something that has virus on it and then touches their mouth, eyes or nose. Avian influenza A virus infections in people happen most often after close, prolonged and unprotected (no gloves or other protective wear) contact with infected birds or other animals. People with close or prolonged contact with infected birds or animals or their contaminated environments are at greater risk of infection.

What to do to protect yourself

• As a general precaution, whenever possible people should avoid direct contact with sick or dead wild birds, poultry, and other animals and observe them only from a distance.
• If you must have direct/close contact with sick or dead wild birds, poultry, or other animals, wear recommended personal protective equipment (PPE). Wild birds can be infected with avian (bird) influenza (flu) A viruses even if they don't look sick.
• Do not touch surfaces or materials (e.g., animal litter or bedding material) contaminated with saliva, mucous, or animal feces from wild or domestic birds or other animals with confirmed or suspected avian bird influenza A virus infection.
• Do not touch or consume raw milk or raw milk products, especially from animals with confirmed or suspected avian influenza A virus infection.

Who is impacted

Information for other groups who have contact with infected birds or other animals

Other groups of people who may have contact with birds or other animals infected or potentially infected with avian influenza A viruses include hunters and people who have backyard or hobbyist flocks. People should report sick birds or other animals or unusual bird or other animal deaths to the state or the federal government, either through their state veterinarian or by calling USDA's toll-free number at 1-866-536-7593. Find additional information on biosecurity for backyard flocks on USDA's APHIS website.

Information for hunters

Hunters who handle wild birds should dress game birds in the field when possible and practice good hygiene to prevent any potential disease spread. If possible, wear gloves, an N95 respirator if available or, if not available, a well-fitting facemask (e.g., a surgical mask), and eye protection when dressing birds. Afterwards, throw away the gloves and facemask and then wash your hands with soap and water. More information on general safety guidelines for hunters handling wildlife and their tissues is available from the U.S. Fish & Wildlife Service's website.

What to do if you find an infected or potentially infected or dead wild bird or other animal

State and local governments have different policies for collecting dead and testing sick or dead animals, so check with your state health department, state veterinary diagnostic laboratory, or state wildlife agency for information about reporting animals that look sick or are dead in your area.

People should avoid unprotected (not using respiratory and eye protection) exposures to sick or dead animals including wild birds, poultry, other domesticated birds, and other wild or domesticated animals. Wildlife agencies regularly investigate reports of sick or dead animals. This type of reporting could help with the early detection of illnesses like West Nile virus or H5N1 bird flu. If local authorities tell you to throw away the bird's carcass (body), don't touch it with your bare hands. Use gloves or a plastic bag turned inside out to place the body in a garbage bag, which can then be thrown away in your regular trash.

What to do if you had direct contact with birds or other animals infected with avian influenza A virus and become sick

CDC has information available for different groups of people who become sick after contact with infected birds.

People who become sick within 10 days of their exposure to infected or potentially infected birds or other animals should isolate at home away from their household members and should not go to work or school until they are proven not to have avian influenza A virus infection. The local or state public health department should be notified and can assist in testing if needed, monitoring and advising when isolation is no longer required.

For more information about bird flu and what to do if you have been exposed to bird flu, visit: What To Know About Bird Flu

Consuming food

Eating uncooked or undercooked poultry or beef can make you sick. While there is no evidence that anyone in the United States has gotten infected with avian influenza A viruses after eating properly handled and cooked poultry products, uncooked poultry and poultry products (like blood) could have been the source of a small number of avian influenza A virus infections in people in Southeast Asia. Visit CDC's Chicken and Food Poisoning web page for instructions on handling poultry safely.

Preparing food

For poultry:

• Cooking poultry and eggs to an internal temperature of 165˚F kills bacteria and viruses, including avian influenza A viruses. People should separate uncooked (raw) poultry from cooked foods and foods that won't be cooked. Cook all poultry and poultry products (including eggs) all the way before eating. More information about safe handling and cooking of poultry can be found here: Chicken and Food Poisoning

For beef:

• Cooking beef to the appropriate internal temperature kills bacteria and viruses, including avian influenza A viruses. Cook all beef products thoroughly before eating. Ground beef should reach a safe internal temperature of 160°F and whole cuts of beef should reach 145°F then rest for 3 minutes. Refer to CDC's safer foods table for a complete list of safe internal temperatures.
• Separate uncooked (raw) beef from cooked foods or foods that won't be cooked to prevent cross-contamination.

Unpasteurized (raw) milk‎ safety

• Choosing pasteurized milk and products made with pasteurized milk is the best way to keep you and your family safe. Unpasteurized (raw) milk and products made from raw milk, including soft cheese, ice cream, and yogurt, can be contaminated with germs that can cause serious illness, hospitalization, or death. Pasteurization kills bacteria and viruses, like avian influenza A viruses, in milk. Make the best decision for your health and the health of your family by always choosing pasteurized milk and products made with it.
• Anyone, even healthy adults, can get sick from drinking unpasteurized (raw) milk.
• Based on the limited research and information available, we do not know at this time if avian influenza A viruses can be transmitted to people through consumption of raw milk and products (such as cheese) made from raw milk from infected cows.
• More information is available at How to Prevent Food Poisoning.

Traveling

Currently, CDC does not recommend against travel to any countries due to avian influenza A viruses in wild birds, poultry, other animals, or people. CDC recommends that travelers to countries and states with H5N1 bird flu outbreaks in animals or people:

• Do not visit poultry farms, bird markets, or other places where live poultry are raised, kept, or sold, if possible. If you must visit such places, wear personal protective equipment and avoid touching poultry or other birds.
• Do not visit dairy farms with sick cows, unless wearing personal protective equipment.
• Do not eat raw or undercooked poultry products and wash your hands after touching uncooked poultry.
• Practice good hygiene.
• Visit a doctor if you become sick during or after travel. Tell the doctor that you might have been exposed to infected birds.

Treatment

CDC currently recommends treatment as soon as possible with flu antiviral drugs for people with suspected or confirmed avian influenza A(H5N1) virus infection. Antiviral treatment works best when started as soon as symptoms begin. If you get sick after being in close contact with infected or potentially infected birds or other animals, contact your state or local health department and a health care provider right away. They may have you tested for H5N1 bird flu, and a health care provider may write you a prescription for an antiviral drug to treat your illness. It's important to take the medication as directed.

Available data on avian influenza A viruses spreading worldwide suggest that avian influenza A virus infections can be treated with current flu antiviral drugs.

Antivirals may also be given soon after unprotected exposure (not using respiratory and eye protection) to a sick person with confirmed or probable A(H5N1) virus infection or after unprotected exposure to sick or dead poultry or other infected animals to help prevent infection and illness.

Vaccination

Getting a seasonal flu vaccine will not protect against H5N1 bird flu

While getting a seasonal flu vaccine only prevents seasonal flu and will not protect against H5N1 bird flu, it is important that people who may have frequent exposure to infected or potentially infected birds or other animals get a seasonal flu vaccine, ideally 2 weeks before their potential exposure. This is because it can reduce the prevalence and severity of seasonal flu and might reduce the very rare risk of coinfection with a human seasonal virus and an avian virus at the same time, and the theoretical risk that reassortment between the two could result in a new virus. Such dual infections, while very rare, could theoretically result in genetic reassortment of the two different influenza A viruses and lead to a new influenza A virus that has a different combination of genes, and which could pose a significant public health concern.

The U.S. Government is developing vaccines against avian influenza A(H5N1) viruses in case they are needed

Seasonal flu vaccines do not provide protection against avian influenza A viruses. CDC has developed H5 candidate vaccine viruses (CVVs) that are nearly identical or, in many cases, identical to the hemagglutinin (HA) protein of recently detected clade 2.3.4.4b avian influenza A(H5N1) viruses in humans, birds and other mammals. These H5 CVVs could be used to produce a vaccine for people, if needed, and preliminary analysis show that they are expected to provide good protection against avian influenza A(H5N1) viruses currently circulating in birds and other animals. More information about Making a candidate Vaccine Virus (CVV) for a Highly Pathogenic Avian Influenza A Virus is available.

If you're a clinician, laboratorian, or public health worker, visit Avian Influenza: Information for Health Professionals and Laboratorians for the latest guidance.

Additional Resources

Avian Flu in the Workplace