The World Health Organisation (WHO) said today that it was now treating all 14 of the bird flu cases announced by Turkish authorities as confirmed.
A Turkish veterinary official in a protective suit tries to collect poultry in the eastern Turkish town of Dogubayazit.
"We are treating the five reported yesterday and the five reported today as cases," said WHO spokeswoman Christine McNab.
The Geneva-based United Nations health agency had previously put the confirmed cases in the outbreak at four, but it raised the figure after Ankara gave details of laboratory tests carried out on the other 10.
Earlier the state-run Anatolian news agency said the virus detected in three people yesterday had been identified in five more people across the country.
The first case of the virus jumping from birds to humans outside China and southeast Asia occurred last week in rural eastern Turkey, where three children from the same family died after contracting the H5N1 strain.
A further three confirmed cases were identified in the capital, Ankara, yesterday, marking a further westward advance of the infection towards the frontiers of Europe.
Turkey's Health Minister Recep Akdag said a total of 14 people across the country have tested positive for bird flu, including three children who died.
But the WHO said there are no signs that the bird flu virus spreading in Turkey is being passed among humans.
"At the moment there is no element in this village indicating human-to-human transmission. It's typically similar to what we have seen so far [in Asia]," Guenael Rodier, head of the WHO's Turkey mission, told reporters.
Confirmed cases of the deadly H5N1 strain in Turkey has prompted EU experts to widen an existing ban on imports and to review existing EU-level surveillance efforts.
But a European Commission spokesman emphasised that there is still no evidence that the virus has become transmissible directly between humans.
The EU banned imports of live birds and poultry products, including feathers, from Turkey, last October, during the last bird flu outbreak.
From today, imports of untreated bird feathers are also banned from countries bordering eastern Turkey - Azerbaijan, Armenia, Georgia, Syria, Iran and Iraq.
Tonight, a joint inquiry team made up of experts from the World Health Organisation, the European Centre for Disease Prevention and Control and the European Commission were in the original Turkish outbreak area of Van.
They were helping support local efforts to isolate the outbreak and establish definitively whether any human-to-human transmission has occurred.
Even if there is no human-to-human transmission, the three confirmed human cases near Ankara, about 620 miles (1,000km) to the west, show the rate of spread of the disease in birds.
A Commission spokesman said: "Obviously it is bad enough that it is affecting birds, but of course we are happy that it has not become a wider problem among the human population and we hope that it remains that way."
The Standing Committee accepted today the Turkish evidence that so far the human deaths from H5N1 have all been due to contracting the virus directly from close contact with diseased poultry.
But the spread westwards suggests that, although the worst-case scenario of human-to-human transmission has not transpired so far, the transmission between birds and poultry is becoming easier.
The Commission insists EU surveillance measures, stepped up last October, are effective. In the last four months about 25,000 wild birds have been tested in the EU for avian flu and all tested negative. "There has been no reported case of H5N1 in the EU to date" emphasised the spokesman.
The latest scare began last week when a Turkish brother and sister aged 14 and 15, died after handling diseased poultry. Their 11-year old sister also died and is believed to have also contracted the H5N1 strain.
They were the first fatalities outside South east Asia, where about 70 people have been killed by the same strain in the last two years. Turkey's mass cull of poultry is due to continue in an attempt to halt the spread of the disease.