Avian influenza; information a key to a correct picture of the situation

The World Health Organization, WHO, arranged an information meeting on the avian influenza on 28 October 2005.

Correct information plays a key role in preventing people from confusing avian influenza and seasonal influenza with a possible influenza pandemic.

Avian influenza is an infectious virus disease of birds and the H5N1 virus is still not easily transmissible to humans or from one human to another. To date, human cases (about 120 in all) have been reported only in Cambodia, Indonesia, Thailand and Viet Nam in Asia, where humans have contracted the disease from infected poultry.

So far, 140 million animals (mainly birds) have got the disease, and this has led to an economic loss of approximately USD 10 billion. Small farmers in the developing countries have been particularly severely hit by the avian influenza, because they do not receive any compensation for their losses.

It is probable that the H5N1 virus will not disappear in the near future in Asia and the likelihood of an influenza pandemic cannot be excluded. H5N1 has to be constantly monitored, and counter-measures and new procedures linked with the feeding and care of animals have to be developed.

An influenza pandemic requires the emergence of a new influenza virus variant (formely unknown to the genetic memory of humans) that would be susceptible to human-to-human infection. According to WHO, a mutation of the virus is probable but has not taken place so far. To become particularly dangerous to humans, the virus has to meet three conditions: to be capable of spreading from birds (often via pigs) to humans, to be capable of causing serious illness in humans, and to be easily transmissible from one human to another.

The present avian influenza strain meets two of the three prerequisites: it has infected humans and caused a very serious illness (over 70% of those who have caught the illness have died), but cases of human-to-human infection are rare. Even if the criteria were fulfilled, the virus may turn out to be of a low pathogenic form and a catastrophe does not necessarily follow.

The severity and onset of the pandemic cannot be predicted. Statistically, pandemics have occurred every 25 to 30 years; the fact that 37 years have elapsed since the latest pandemic in 1968 is a sufficient reason to get prepared. Preparations at the national and international levels are of crucial importance.

At present, priority is given to efforts to minimize human infections and to monitor the situation among the bird population. From the point of view of preparedness for a pandemic, it is essential to monitor and halt the spread of the virus.

Several international meetings focusing on efforts to strengthen international preparedness have been held during this autumn. A Global Meeting, co-organized by WHO, the Food and Agriculture Organization FAO, the World Organization for Animal Health OIE and the World Bank, is scheduled to convene in Geneva from 7 to 9 November 2005 to discuss avian influenza and influenza pandemic. Experts are expected to coordinate international cooperation and compile a plan of action consisting of the best practices to combat an influenza pandemic.