People wear anti-flu masks while walking in a street in Kiev, Ukraine,Tuesday, Nov. 3, 2009. Russia and Slovakia tightened their borders with Ukraine on Tuesday as the World Health Organization began investigating a suspected swine flu outbreak. The death toll from flu has climbed to 71 since the outbreak struck last week in the western city of Ternopil, Prime Minister Yulia Tymoshenko said. AP Photo logo AP Photo 3 weeks ago

People wear anti-flu masks while walking in a street in Kiev, Ukraine,Tuesday, Nov. 3, 2009. Russia and Slovakia tightened their borders with Ukraine on Tuesday as the World Health Organization began investigating a suspected swine flu outbreak. The death toll from flu has climbed to 71 since the outbreak struck last week in the western city of Ternopil, Prime Minister Yulia Tymoshenko said.