The World Health Organization has confirmed two more human deaths from bird flu in Indonesia, bringing the country's death toll from the virus to 18.

The confirmation from a Hong Kong laboratory came Sunday after local tests showed that two women who died last week had contracted the deadly H5N1 strain of the virus.

Recent tests have also confirmed the H5N1 bird flu was found in wild swans in Italy, Greece and Bulgaria.  Officials in Romania have also reported new cases of suspected bird flu in the Danube Delta. 

Italian veterinary officials are holding an emergency meeting Sunday, and in Greece, experts are checking poultry farms and homes (around the northern city of Thessaloniki) where the infected birds were found.

Bird flu has killed about 90 people worldwide since 2003.  Experts say migratory birds are spreading the virus.

World health officials are working to prevent a global pandemic.