First Human Infection With Avian Influenza A(H5N1) Virus Since Sept. 2017 Reported in Nepal

May 6, 2019 — The first human infection with an avian influenza A(H5N1) virus (H5N1 bird flu) since September 2017 has been reported in Nepal. This is the South Asian country’s first human infection with H5N1 bird flu.

Nepal has been experiencing sporadic outbreaks of H5N1 bird flu among poultry in recent months. Asian-lineage H5N1 viruses have been associated with poultry outbreaks in Asia, the Middle East, Europe and Africa since 2003. These outbreaks have been associated with high mortality in poultry and rare human infections. Nepal becomes the 17th country worldwide to report a human infection with this virus.

Most human infections with bird flu viruses have been associated with exposure to infected birds or contaminated environments, such as poultry farms or live poultry markets. Human infections with bird flu are reportable to the World Health Organization (WHO). Since 2003, 860 human infections have been reported, with about half of those people dying. Instances of person-to-person spread of Asian H5N1 viruses have been very rare, and no ongoing sustained community spread of this virus has occurred. In Nepal, no additional suspected human H5N1 bird flu infections have been reported since this first illness was identified in March.

CDC has been working with Nepal since 2009 to strengthen influenza surveillance and improve their capacity to detect novel flu viruses with the potential to cause a pandemic. CDC’s regional office in Asia works closely with Nepal on a regular basis to support their outbreak and response efforts.

Nepal’s National Public Health Laboratory (NPHL) is the country’s National Influenza Center, and participates in global influenza surveillance. NPHL identified the sample from the sick patient as being an unsubtypable influenza A virus and sent the sample to the WHO Collaborating Center in Japan for further testing. As required by the International Health Regulations (IHR), Nepal reported this infection to WHO.

No human infections with Asian H5N1 viruses have been reported in the United States, and the report of a single H5N1 infection in Nepal poses no direct risk to any U.S. resident. The H5N1 bird flu viruses occasionally detected in U.S. poultry are different from Asian-lineage H5N1 viruses. While the risk of infection posed by bird flu is low, CDC does recommend general precautions to reduce the risk of an avian influenza infection:

Protective actions around birds

  • As a general precaution, people should avoid wild birds and observe them only from a distance
  • Avoid contact with domestic birds (poultry) that appear ill or have died
  • Avoid contact with surfaces that appear to be contaminated with feces from wild or domestic birds

Traveling to other countries

  • Currently, CDC does not recommend any travel restrictions to any of the countries affected by avian influenza viruses in poultry or people.
  • CDC does recommend that travelers to countries with avian influenza A outbreaks in poultry or people observe the following:
    • Avoid visiting poultry farms, bird markets and other places where live poultry are raised, kept, or sold.
    • Avoid preparing or eating raw or undercooked poultry products.
    • Practice hygiene and cleanliness.
    • Visit a doctor if you become sick during or after travel.
    • Visit CDC Travelers’ Health for more information on avian influenza.

If you’ve had direct contact with infected birds

  • People who have had direct contact with infected bird(s) should be watched if they become ill. They may be given influenza antiviral drugs to prevent illness.
  • While antiviral drugs are most often used to treat flu, they also can be used to prevent infection in someone who has been exposed to influenza viruses. When used to prevent seasonal influenza, antiviral drugs are 70% to 90% effective.
  • Close contacts (family members, etc.) of people who have been exposed to avian influenza viruses are being asked to monitor their health and report any flu-like symptoms.

If you’re a clinician, laboratorian or public health worker

For more information on bird flu, visit CDC’s website at

For more information about CDC’s activity in Nepal, visit

For the full WHO report on the H5N1 infection in Nepal, visit