Avian Influenza Infection
Avian influenza (bird flu) is an influenza virus that spreads among birds. Rarely, the virus can spread to people who have had close contact with infected birds. Avian influenza causes a flu-like illness in people which can be severe.
Birds shed influenza virus in their droppings, saliva and nasal secretions, spreading it onto their feathers.
People are usually infected through having close contact with infected birds, or surfaces which are contaminated with bird secretions:
- Visiting bird enclosures or wet markets where birds have been recently kept increases your risk of becoming infected.
- Very rarely, people can go on to infect other people with the virus from having exposure to the infected person's body secretions.
- In special circumstances, antiviral drugs may be prescribed by your doctor if you are considered to be to be at 'high risk' of illness.
- The European Centre for Disease Prevention and Control has advised that 'It is not recommended that travellers take Oseltamivir (Tamiflu) with them'.
Please see the Avian Influenza (Travel Advice) page for ways of reducing your risk from avian influenza when travelling.
There are many different strains of avian influenza virus, but the ones that have caused most problems in humans are called H5N1 and H7N9.
Avian influenza infection in birds occurs worldwide. Human infection with these viruses could therefore occur anywhere.
- Most human cases have occurred in Asia and North Africa.
- China, Egypt, Indonesia and Vietnam have reported the largest number of human cases.
- The risk is greatest where there is close contact between people and potentially infected birds.
It usually only takes 3 - 5 days for symptoms to develop after exposure to the virus.
The illness can vary from being mild to becoming very severe.
Early symptoms are likely to be similar to normal 'flu-like' symptoms such as:
- High temperature (fever)
- Aching muscles
- Sore throat
Occasionally, some people develop other symptoms such as:
- Feeling sick (nausea) or vomiting
If your symptoms affect your breathing; or you begin to feel severely unwell, you should seek medical advice as soon as possible. You should call for advice in the first instance if, in the 10 days before illness, you:
- visited a country with an outbreak of avian influenza, and had contact with live poultry or pigs or their environments OR
- had close contact with someone known to have avian influenza.
Antiviral drugs, oseltamivir (Tamiflu) and zanamivir (Relenza) can be used for treatment.
At present there is no vaccine available for people against avian influenza. In the event of a large outbreak a vaccine could be manufactured within months.
- The European Centre for Disease Prevention and Control
- Centre for Disease Control (Atlanta)
- World Health Organization
- World Organisation for Animal Health (OIE)
- Health Protection Scotland