CDC

What is the current situation?

As of January 16, 2017, Chinese health authorities have confirmed 120 new human cases of avian influenza A (H7N9) to the World Health Organization since September 2016. Most of these patients reported exposure to live poultry or poultry markets. A few cases of H7N9 have been reported outside of mainland China but most of these infections have occurred among people who had traveled to mainland China before becoming ill. CDC advises people traveling to China to avoid contact with poultry (including poultry markets and farms), birds, and their droppings and to avoid eating undercooked poultry. Infected birds that appear healthy may still be able to transmit this virus to humans. There are no recommendations against travel to China.

What is avian influenza A (H7N9)?

Avian influenza A (H7N9) is a virus found in birds that does not normally infect humans. However, in the spring of 2013, the first human cases of H7N9 virus infection were reported in China. Since then, 924 laboratory-confirmed cases of human infection with H7N9 virus have been reported, with about one-third of cases resulting in death. Most of these infections have been associated with exposure to infected poultry or contaminated environments (such as poultry markets) in China. In rare cases, limited, non-sustained  person-to-person spread of H7N9 virus likely occurred, but there is no evidence of sustained human-to-human infection. Early symptoms are similar to those of other respiratory viruses, including seasonal flu and may include fever, cough, sore throat, muscle aches and fatigue, loss of appetite, and runny or stuffy nose. However, infection with this virus often causes severe respiratory illness and, in some cases, death (see http://www.cdc.gov/flu/avianflu/h7n9-virus.htm). Risk factors for severe and fatal outcomes include older age and having certain chronic medical conditions.

What can travelers do to protect themselves?

There is no vaccine available to prevent H7N9 virus infection. To protect yourself when visiting China, take the following steps:

• Do not touch birds.
  • Don’t touch birds, whether they are alive or dead.
  • Avoid live bird or poultry markets, including where birds are slaughtered (wet markets).
  • Avoid  places that might be contaminated with bird feces. .
• 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).
  • As a general precaution, don’t eat or drink dishes that include blood from any animal.
  • As a general precaution, 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.
• If you feel sick after visiting China:
  • Talk to your doctor or nurse if you feel seriously ill, especially if you have a fever, cough, or shortness of breath.
  • Tell your health care provider about your travel to China.
  • For more information about medical care abroad, see Getting Health Care Abroad (https://wwwnc.cdc.gov/travel/page/getting-health-care-abroad)
  • Avoid contact with other people while you are sick.

Clinician information

Clinicians should consider the possibility of avian influenza A (H7N9) virus infection in people presenting with respiratory illness within 10 days of travel to China, particularly if the patient reports exposure to birds or poultry markets. Although most H7N9 cases have resulted in severe respiratory illness, infection may cause mild illness in some people, including both adults and children. Guidance for clinicians who suspect avian influenza A (H7N9) virus infection in a returned traveler from China is available. Clinicians should initiate infection control precautions (airborne, droplet, and contact), obtain appropriate specimens, and notify their local or state health department promptly. State health departments should notify CDC of suspected cases within 24 hours. Empiric treatment with influenza antiviral medications may be warranted while testing is pending.

Note that influenza diagnostic testing in patients with respiratory illness of unknown etiology may identify human cases of avian influenza A virus infection. Patients with H7N9 virus infection are expected to have a positive test result for influenza A virus via reverse-transcription polymerase chain reaction (RT-PCR testing), although most assays will not be able to determine the influenza virus subtype. Use of rapid influenza diagnostic tests are not recommended if H7N9 virus infection is suspected.

Additional information

• Avian Influenza A (H7N9) Virus (CDC)
• Avian Influenza: Information for Health Professionals and Laboratorians