The Croatian government on Friday announced the country's first swine flu case in a woman who had recently returned from Australia.
"The first case of the A(H1N1) pandemic virus was confirmed in Croatia," Health Minister Darko Milinovic told reporters.
The virus was found in a 60-year-old woman from the central coastal town of Split, who returned there from Sydney on Wednesday, he said.
The woman, who sought medical help at a Split hospital a day later after she developed flu symptoms, was released home, the minister added.
Tests were carried out in a local laboratory.
Last month Croatia denied a first swine flu case had been detected after positive results of a test, carried out in a London laboratory, turned out to be false.
Data released by the World Health Organisation earlier Friday showed that 125 countries and territories have been infected since the new A(H1N1) influenza virus was uncovered in Mexico and the United States in April.
Nearly 90,000 cases were confirmed by laboratory tests, including 382 deaths.