Bulgaria tested dozens of waterfowl found dead in its wet zones on Saturday, a day after it detected its first case of bird flu in a sick swan that could be dangerous to humans.

"We received some 26 dead wild birds today and we took samples for testing. The tests take four days," Bulgaria's chief veterinarian Zheko Baichev said.

Bulgaria stepped up surveillance on its wet zones along the Danube river and Black Sea and called for people to report any dead birds after it detected its first case of H5 avian flu on Friday.

Bulgaria will send a sample from the infected dead swan, found on the Danube River banks in northwestern Bulgaria, to a lab in Britain on Monday to investigate whether it is the highly pathogenic H5N1 strain, Baichev said. Results are due in a week.

Seven swans and a white-headed goose were found dead at Shabla lake, while another eight dead swans were found at the Durankulak lake, the environmental ministry said.

The two lakes near the Black Sea coast close to the border with Romania lie along the Pontic migratory route, on which birds travel south from northern Russia and Scandinavia to northern Africa.

Other birds were found dead along lakes and rivers across the country, state news agency BTA reported.

Sandwiched between Romania and Turkey, which have both been hit by outbreaks of the deadly H5N1 strain, Bulgaria has been seen as a possible destination for the virus.

(Chinadaily.com via agencies February 5, 2006)