Influenza A (H7N9) Virus: Information for the General Public

What is H7N9?
Some influenza A viruses occur naturally in birds and can cause illness in those animals—these viruses are called “avian flu viruses”. While avian flu viruses do not always infect humans, occasional human infections have occurred. Human infections usually occur after close contact with infected birds (either live or dead) or areas contaminated with an avian flu virus.

Like many influenza viruses, there are different strains of the influenza A (H7N9) virus, or H7N9. Beginning in March 2013, China reported human and bird infections with a new strain of H7N9 that is very different from the H7N9 viruses that were seen previously.

How can a person get H7N9?
No cases of human or bird infections with this virus have been seen in the United States at this time. In China, the virus has been found in birds (poultry) and people; over one hundred cases of human infection with H7N9 have also been reported. Investigators believe that people became infected with the virus after having direct contact with infected birds or contact with areas contaminated by infected birds. Birds can contaminate an area/environment through their droppings or mucus.

How is H7N9 spread?
Most of the human cases of H7N9 in China had exposure to poultry. Some limited spread from person-to-person has likely taken place in China; however, ongoing (sustained) transmission has not occurred.

What are the symptoms of H7N9 infection?
The symptoms of H7N9 infection generally start with high fever and cough. Many of the cases have progressed to very serious illness, including severe pneumonia, acute respiratory distress syndrome (ARDS), septic shock, and multi-organ failure leading to death.

Is there a vaccine for H7N9 infection?
Currently, there is no vaccine for H7N9 infection. Scientists have taken early steps to identify a strain of the virus that could be used to make a vaccine if it is needed. The seasonal flu vaccine will not protect against H7N9. Seasonal flu vaccines protect against seasonal influenza viruses. CDC recommends that everyone 6 months and older get a seasonal flu vaccine each year.

What is the treatment for H7N9 infection?
The same influenza antiviral drugs that are used to treat seasonal flu are used to treat H7N9 infection. However, there is some evidence that the H7N9 viruses might be less susceptible (sensitive) to the currently recommended drugs (oseltamivir and zanamivir).

How can I reduce the likelihood of getting H7N9 infection?

  • Since H7N9 is not spreading easily from person-to-person at this time, CDC does not recommend that people delay or cancel trips to China.
  • CDC advises travelers to China to take common-sense precautions, including following good hand hygiene and food safety practices and avoiding contact with animals. CDC recommendations include:
    • Do not touch birds, pigs, or other animals. Do not touch animals whether they are alive or dead. Avoid live bird or poultry markets and other markets or farms with animals.
    • Eat food that is fully cooked. Eat meat and poultry that is fully cooked (not pink) and served hot. Eat hard-cooked eggs (not runny). Don’t eat or drink dishes that include blood from any animal. Don’t eat food from street vendors.
    • Practice hygiene and cleanliness. Wash your hands often. If soap and water aren’t available, clean your hands with hand sanitizer containing at least 60% alcohol. Don’t touch your eyes, nose, or mouth. If you need to touch your face, make sure your hands are clean. Cover your mouth and nose with a tissue or your sleeve (not your hands) when coughing or sneezing. Try to avoid close contact, such as kissing, hugging, or sharing eating utensils or cups, with people who are sick.
    • See a doctor if you become sick during or after travel to China. See a doctor right away if you become sick with fever, coughing, or shortness of breath. Delay your travel home until after you have recovered or until your doctor says it is okay to travel. If you get sick with fever, coughing, or shortness of breath within 10 days after you return to the United States, tell your doctor about your recent travel to China.

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