A German tropical disease institute is examining two women for possible bird flu infection.
A female holidaymaker returning to Germany from a vacation in Thailand was being checked for bird flu symptoms at the Bernhard Nocht Institute for Tropical Medicine.
A woman who had accompanied her was also being examined at the institute. Initial tests conducted on the two women have not confirmed the presence of the virus.
In Asia, two more people, a 58-year-old-woman in Thailand and a teenage boy in Vietnam, have died after contracting the flu.
Their deaths bring to 12 the toll in an epidemic that is sweeping Asia and which scientists fear may now be transmitted from person to person.
The WHO says two sisters who died in Vietnam last month probably caught the virus from their brother - the first cases of human-to-human infection in the current epidemic.
The UN Food and Agriculture Organisation, the World Animal Health Organisation and the WHO will convene an urgent meeting of experts in Rome tomorrow to discuss the avian flu crisis.
They hope to chart out a co-ordinated response strategy.
