Avian Influenza

Avian influenza or “bird flu” is a very infectious disease of birds caused by type A strains of the influenza virus (H5N1 and H7N9). These viruses occur naturally in birds and have a global distribution. Wild birds carry the virus and are mostly resistant to disease. Domesticated birds such as chickens, ducks and turkeys are very susceptible to infection and high mortality rates can be expected when exposed.

Avian influenza remains a bird disease. While almost 900 people have been infected since December 1997, there is little evidence to suggest the virus can easily pass from person to person or have sustained transmission. Most cases have a link to sick birds and have occurred in Indonesia, Vietnam, Egypt, China and Cambodia. Travellers should generally avoid the “live” section of markets in Asia where caged birds are sold.

Much has been spoken about the risk of a global pandemic. This is based on historical facts relating to previous pandemics in 1918/19, 1957/8 and 1968.  Influenza A viruses are quite unstable and can change their structure. Should an Avian influenza virus such as H5N1 take on characteristics of human influenza then it might be able to pass more easily from person to person. While the risk for a global pandemic remains low it would be folly for national health authorities to ignore the warnings and not develop strategies to slow an outbreak should it occur. A vaccine would have to be developed and this would take some months. Antiviral medications such as Tamiflu or Relenza, if given within 24 hours of symptoms, may reduce illness se-verity.

Pandemic influenza is not just a travel issue, it is a community issue.  Unlike SARS, which was effectively controlled through case identification, isolation and quarantine, influenza is much more difficult. People with influenza can have few symptoms and still be infectious at the start of the illness.

While the flu vaccine would give no protection against H5N1, it might eliminate human influenza A as a differential diagnosis should the individual experience a flu-like illness. Unless intending to be a resident in a high-risk location, there is no need to consider travelling with antiviral medication.

The risk of Avian Influenza in travellers is low.

Travellers should:

• Avoid or reduce exposure to areas with live poultry, such as live animal markets and poultry farms. Large amounts of the virus are excreted in the droppings from infected birds. Ducks can excrete large amounts of H5N1 but appear quite well.
• Seek medical attention as soon as possible if you develop severe respiratory symptoms. The use of antiviral medications within 48hrs of exposure can reduce the illness duration and severity.

What about food safety?

• Influenza viruses are killed by adequate heat. The importance of good hygiene practices during handling of poultry products, including hand washing, prevention of cross-contamination and thorough cooking (70°C) cannot be over emphasized. Travellers are advised to pay close attention to the rules of eating and drinking.
• Strictly observe the rules of eating and drinking safely. Wash your hands often using either soap and water, or alcohol-based hand sanitizers. This removes potentially infectious materials from your skin and helps prevent disease transmission.
• Consume only well-cooked food. Influenza viruses are destroyed by heat; therefore, as a precaution, poultry food including eggs should be thoroughly cooked. This will also reduce your chance of getting some serious bacterial illnesses such as salmonella and campylobacter.

The situation regarding Avian flu may change quickly: For further monitoring, see: CDC and WHO