As local officials were sealing off parts of the major cities of Ankara and Istanbul and thousands of birds were being culled, Guenael Rodier, head of a World Health Organization (WHO) team sent to investigate the outbreak said he believes the outbreak can be brought under control relatively easily.

Rodier says it is unclear why so many people have been infected in Turkey so quickly, but it is possible there is now a more efficient transmission from animals to humans.

He says it is unclear why the fatality rate is relatively low with just two confirmed deaths to date.

In an attempt to calm fears, Turkish Prime Minister Tayyip Erdogan has said that none of the latest human victims are in a life-threatening condition and has urged Turks not to panic.

Following the death of two children last week from bird flu in eastern Turkey, whose dead sister is also a suspected victim, Turkish hospitals have been overwhelmed by people demanding tests for the virus.

Turkish authorities have reported that at least twelve people are infected with the virus, and most are children, but apparently more than half of people undergoing tests for bird flu in Istanbul have tested negative.

The confirmation of cases as far west as the central region around the capital Ankara has generated fear that the disease is heading for mainland Europe.

The cases in Turkey are the first incident of the virus in people outside east Asia since it reemerged in late 2003.

To date the virus has killed at least 78 people, including two deaths in China recently reported by the WHO.

According to the WHO all the Turkish victims appear to have contracted the disease from close contact with infected poultry, dismissing fears it was spreading from person to person.

Since December 26 more than 300,000 poultry have been culled, but experts still fear the H5N1 strain of bird flu may mutate enough to allow it to pass easily among humans, sparking a pandemic in which millions of people could die.

Following the report of another human case of bird flu on Tuesday in the central province of Sivas, Prime Minister Erdogan insists the situation is under control and will continue to be monitored closely.

Meanwhile snow and freezing temperatures in the east of the country are affecting efforts to tackle the virus and may in fact be enhancing it’s survival capacity.

The admission of four people to hospital with suspected bird flu near the Aegean coast adds to concern the country’s important tourist trade will be jeopardised.

Apparently authorities in countries bordering Turkey are disinfecting cars crossing from Turkey and checking luggage as they try to halt the spread of the virus.

To date the number of provinces where birds have been found to be infected has risen to19.

They include the western provinces of Istanbul and Bursa as well as Ankara, areas near the Black Sea in the north and areas in the east extending to borders with Iran and Armenia.

Teams of veterinarians have been sent into a number of regions to cull poultry clad in protective white body suits, regarded as the best method of checking the disease.

But according to the mayor of the eastern village of Dogubayazit, home to the children who died, many people were hiding their poultry because they did not believe government promises that they would be fully compensated.