The avian influenza virus statistically kills 40-60% of the people it infects, i.e. it is very aggressive, causing major concern and fear in communities, in the food and agriculture sectors, in health systems and for the World Health Organization (WHO).

The H5N1 form of avian influenza, which is causing ever more widespread outbreaks in poultry since 2003 in many South East Asian countries and more recently in South Asia, Europe, Africa and the Middle East, has the potential to change and develop into even more dangerous strains or into a human strain. It could then cause large global outbreaks and epidemics (pandemics).

Pandemic influenza is a term used to describe a worldwide epidemic of human influenza. It means that the virus emerges from one location and spreads very quickly throughout the world. During the last millennium this happened three times:

• 1918 – the Spanish flu pandemic infected 20% of the world’s population (estimated 40 million deaths)
• 1957 and 1968 pandemics caused many deaths throughout the world

The avian influenza strain, which is currently circulating in parts of Asia and more recently in the Middle East, Africa and Europe, is highly pathogenic, which means it is highly contagious for birds, lethal for chickens and other bird species.

Scientists and WHO predict that the world is now closer to a pandemic than in the past 50 years. A pandemic virus is highly contagious and can spread quickly within a short space of time.

The symptoms of avian influenza are very similar to normal seasonal flu. The main symptoms are:

• fever (above 38ºC)
• muscle aches
• serious cough
• shortness of breath
• fatigue

1. Basic hygiene measures, such as regular hand washing and covering your mouth when you cough, are generally sufficient to prevent the spread of diseases, including avian and human influenza.

2. Specifically for avian influenza, avoid contact with sick or dead poultry and ensure that all poultry meat and eggs are well cooked. The influenza virus is killed at cooking temperatures over 70ºC.

If there is a pandemic of influenza, you might be asked to avoid crowded places (such as markets) and to stay at home from work to prevent the spread of the disease. You are recommended to observe basic hygiene measures and ensure that masks are available. This will protect you from catching the disease when you have to go out in public. Masks worn properly also protect your family, if you or someone else in your family is infected.

No, there is no avian influenza vaccine for humans, only for poultry. Vaccines are being developed, but none are proven safe and effective in humans yet. Prototype vaccines are in the pipeline, but it will take several months to produce enough vaccines, and by that time, they may not be effective against avian influenza because it changes its genetic composition frequently. Influenza vaccines for use in humans are normally developed by using fertilized eggs. For avian influenza this does not work. The virus is so lethal that it kills the chicken embryo.

Vaccines are available only for normal seasonal human influenza. Overall, protection is about 70% effective to prevent people from becoming ill. However immunized persons, who get flu, tend to get a (much) milder form. Producers are few (Great Britain, France and with relatively small percentage manufactured in the USA, Canada ad Japan). Today, maximum production capacity is only 300 million doses, enough to protect about 5% of the world’s population. This warrants careful targeting.

Note 1: There is a northern hemisphere vaccine and one for the southern hemisphere. Please consult a doctor on which one is applicable in your case.

Note 2: The very young, those with other chronic diseases, health care workers and people above 50, should be the prime target for immediate immunization.

Note 3: A human influenza vaccine will provide little or no protection against avian influenza, but would avoid avian influenza cases to occur concomittantly in one person.

The avian influenza virus changes its genetic composition; it can become more aggressive and more infectious to humans. Moreover, it incorporates genetic material from other viruses, also changing its behaviour. This is exactly what happened in the global influenza pandemics of 1918.

The main concern now is that the avian influenza strain may develop the capacity to spread from person to person via coughing, sneezing and close contact with infected people within a not too distant future. So far, there is no evidence that it has happened, but if this happens, it will pose a serious global threat, depending on the efficiency of quick containment at source.