International travel and health

Avian influenza in humans

23 January 2014 - Some avian influenza (“Bird Flu”) viruses can infect humans and cause disease. These include H5N1, H7N3, H7N7, H7N9 and H9N2. Some of these infections have been very severe and some have resulted in deaths, but many infections have been mild or even subclinical in humans.

Symptoms of avian influenza in humans have ranged from typical human influenza-like symptoms (fever, cough, sore throat, and muscle aches) to eye infections, pneumonia, severe respiratory diseases (such as acute respiratory distress syndrome), and other severe and life-threatening complications.

Avian influenza infections in birds or humans are observed in parts of Asia, Europe, the Middle East, and Africa. During an outbreak of avian influenza among poultry, there is a possible risk of infection to people who have contact with infected birds or surfaces that have been contaminated with secretions or excretions from infected birds. With certain types of avian influenza, human infection may occur even though there is no apparent outbreak among poultry. However, the risk from avian influenza is generally low to most people. Infection cannot result from properly handled and cooked poultry and eggs.

WHO does not recommend any travel restrictions to affected countries. However, WHO advises that travellers to countries with known outbreaks of avian influenza avoid poultry farms, contact with animals in live bird markets, being close to areas where poultry may be slaughtered, and any surfaces that appear to be contaminated with faeces from poultry or other animals. Travellers should also wash their hands often with soap and water and avoid eating undercooked eggs.

A diagnosis of infection with an avian influenza virus should be suspected in individuals who develop influenza-like symptoms while travelling or soon after return from an area where avian influenza is a concern. Travellers should be advised that if exposure to individuals with suspected avian influenza illness or severe, unexplained respiratory illness occurs, and they in turn develop symptoms, they should urgently consult health professionals.

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