Bird market Asia Photo: World Bank

The European Commission will adopt a decision to ban untreated feathers from Azerbaijan, Armenia, Georgia, Syria, Iran and Iraq, due to the proximity of these countries to Eastern Turkey where there is currently an outbreak of the H5N1 avian influenza virus in poultry.

This decision follows a positive opinion by Member States at a meeting of the Standing Committee on the Food Chain and Animal Health (SCFCAH) today. The complete ban on any imports of live birds and poultry products from Turkey, which was adopted in early October 2005, remains in place. The Member States experts also discussed the situation with regard to Member States' surveillance for avian flu in the EU. Since the heightened surveillance measures were established by the Commission last October, around 25000 wild birds have been tested for avian influenza in the EU in late 2005. All samples have tested negative for the virus and there has been no reported case of H5N1 in the EU to date.

With regard to the latest public health situation in Turkey, the most recent figures from the Turkish authorities indicate that there are now 9 confirmed human cases of avian flu (6 in Eastern Turkey and 3 in Ankara) out of a total of 48 suspected cases under investigation. The joint WHO, European Commission/FAO/OIE and European Centre for Disease Prevention and Control (ECDC) expert team reached the outbreak area in Van late last night and started work investigating the epidemiological situation there this morning. This team of experts will also provide support for the Turkish authorities in dealing with the situation, and establish further needs that Turkey might have in terms of international help.

The Ministry of Health in Turkey has confirmed an additional two cases of human infection with the H5N1 avian influenza virus. Both cases are children, aged five and eight years, and both are hospitalized. This brings the total number of laboratory confirmed cases in Turkey to four. Two of these cases were fatal.

A WHO collaborating laboratory in the United Kingdom has today confirmed detection of the H5N1 virus in samples taken from the two fatal cases.

The Ministry of Health has also announced a third death, presumably caused by the H5N1 virus, in a 12-year-old girl. The girl, who died on 6 January, is a sibling of the two children who died. A fourth child in the family, a six-year-old boy, is also hospitalized. Tests on samples from these patients are ongoing; neither is laboratory confirmed at present.

According to Turkish authorities, some 30 patients are being treated and evaluated for possible H5N1 infection at a hospital in Van Province. Most of the patients are children, and the majority come from the rural district of Dogubayazit.

Plans for a team of international experts to travel today to Van Province have been deferred because of adverse weather conditions. Government officials are assisting the team in finding a rapid mode of transportation to the affected area in the eastern part of the country.

To date, all evidence indicates that patients have acquired their infections following close contact with diseased poultry. Contact between people and poultry has likely increased during the present cold weather, when the custom among many rural households is to bring poultry into their homes. Tests have shown that the virus can survive in bird faeces for at least 35 days at low temperatures (4^oC).

Based on experiences during the avian H5N1 outbreaks in Asia, behaviours that carry an especially high risk of infection include the slaughtering, defeathering, butchering, and preparation for consumption of diseased poultry. These behaviours tend to occur most frequently in rural areas where populations traditionally slaughter and consume birds once deaths or signs of illness are seen in poultry flocks.

In recent days, vigilance for outbreaks of the disease in poultry has increased considerably. Outbreaks of highly pathogenic H5N1 avian influenza have now been confirmed in six provinces in the eastern and south-eastern part of the country. Outbreaks at additional sites in the area are under investigation.

Avoidance of high-risk behaviours remains the most important way for local populations to protect themselves from infection.

1. Pandemic influenza is different from avian influenza.

Avian influenza refers to a large group of different influenza viruses that primarily affect birds. On rare occasions, these bird viruses can infect other species, including pigs and humans. The vast majority of avian influenza viruses do not infect humans. An influenza pandemic happens when a new subtype emerges that has not previously circulated in humans.

For this reason, avian H5N1 is a strain with pandemic potential, since it might ultimately adapt into a strain that is contagious among humans. Once this adaptation occurs, it will no longer be a bird virus--it will be a human influenza virus. Influenza pandemics are caused by new influenza viruses that have adapted to humans.

2. Influenza pandemics are recurring events.

An influenza pandemic is a rare but recurrent event. Three pandemics occurred in the previous century: “Spanish influenza” in 1918, “Asian influenza” in 1957, and “Hong Kong influenza” in 1968. The 1918 pandemic killed an estimated 40–50 million people worldwide. That pandemic, which was exceptional, is considered one of the deadliest disease events in human history. Subsequent pandemics were much milder, with an estimated 2 million deaths in 1957 and 1 million deaths in 1968.

A pandemic occurs when a new influenza virus emerges and starts spreading as easily as normal influenza – by coughing and sneezing. Because the virus is new, the human immune system will have no pre-existing immunity. This makes it likely that people who contract pandemic influenza will experience more serious disease than that caused by normal influenza.

3. The world may be on the brink of another pandemic.

Health experts have been monitoring a new and extremely severe influenza virus – the H5N1 strain – for almost eight years. The H5N1 strain first infected humans in Hong Kong in 1997, causing 18 cases, including six deaths. Since mid-2003, this virus has caused the largest and most severe outbreaks in poultry on record. In December 2003, infections in people exposed to sick birds were identified.

Since then, over 100 human cases have been laboratory confirmed in four Asian countries (Cambodia, Indonesia, Thailand, and Viet Nam), and more than half of these people have died. Most cases have occurred in previously healthy children and young adults. Fortunately, the virus does not jump easily from birds to humans or spread readily and sustainably among humans. Should H5N1 evolve to a form as contagious as normal influenza, a pandemic could begin.

4. All countries will be affected.

Once a fully contagious virus emerges, its global spread is considered inevitable. Countries might, through measures such as border closures and travel restrictions, delay arrival of the virus, but cannot stop it. The pandemics of the previous century encircled the globe in 6 to 9 months, even when most international travel was by ship. Given the speed and volume of international air travel today, the virus could spread more rapidly, possibly reaching all continents in less than 3 months.

5. Widespread illness will occur.

Because most people will have no immunity to the pandemic virus, infection and illness rates are expected to be higher than during seasonal epidemics of normal influenza. Current projections for the next pandemic estimate that a substantial percentage of the world’s population will require some form of medical care. Few countries have the staff, facilities, equipment, and hospital beds needed to cope with large numbers of people who suddenly fall ill.

6. Medical supplies will be inadequate.

Supplies of vaccines and antiviral drugs – the two most important medical interventions for reducing illness and deaths during a pandemic – will be inadequate in all countries at the start of a pandemic and for many months thereafter. Inadequate supplies of vaccines are of particular concern, as vaccines are considered the first line of defence for protecting populations. On present trends, many developing countries will have no access to vaccines throughout the duration of a pandemic.

7. Large numbers of deaths will occur.

Historically, the number of deaths during a pandemic has varied greatly. Death rates are largely determined by four factors: the number of people who become infected, the virulence of the virus, the underlying characteristics and vulnerability of affected populations, and the effectiveness of preventive measures. Accurate predictions of mortality cannot be made before the pandemic virus emerges and begins to spread. All estimates of the number of deaths are purely speculative.

WHO has used a relatively conservative estimate – from 2 million to 7.4 million deaths – because it provides a useful and plausible planning target. This estimate is based on the comparatively mild 1957 pandemic. Estimates based on a more virulent virus, closer to the one seen in 1918, have been made and are much higher. However, the 1918 pandemic was considered exceptional.

8. Economic and social disruption will be great.

High rates of illness and worker absenteeism are expected, and these will contribute to social and economic disruption. Past pandemics have spread globally in two and sometimes three waves. Not all parts of the world or of a single country are expected to be severely affected at the same time. Social and economic disruptions could be temporary, but may be amplified in today’s closely interrelated and interdependent systems of trade and commerce. Social disruption may be greatest when rates of absenteeism impair essential services, such as power, transportation, and communications.

9. Every country must be prepared.

WHO has issued a series of recommended strategic actions [pdf 113kb] for responding to the influenza pandemic threat. The actions are designed to provide different layers of defence that reflect the complexity of the evolving situation. Recommended actions are different for the present phase of pandemic alert, the emergence of a pandemic virus, and the declaration of a pandemic and its subsequent international spread.

10. WHO will alert the world when the pandemic threat increases.

WHO works closely with ministries of health and various public health organizations to support countries' surveillance of circulating influenza strains. A sensitive surveillance system that can detect emerging influenza strains is essential for the rapid detection of a pandemic virus.

Six distinct phases have been defined to facilitate pandemic preparedness planning, with roles defined for governments, industry, and WHO. The present situation is categorized as phase 3: a virus new to humans is causing infections, but does not spread easily from one person to another.

More information from WHO