A man adjusts his mask, a precaution against flu, while walking in the western Ukrainian city of Lviv,  Wednesday, Nov. 4, 2009. Russia and Slovakia have tightened their borders with Ukraine as the World Health Organization began investigating a suspected swine flu outbreak. The European Union says it is coordinating closely with health experts in Ukraine to help it cope with a suspected swine flu outbreak. AP Photo logo AP Photo 3 weeks ago

A man adjusts his mask, a precaution against flu, while walking in the western Ukrainian city of Lviv, Wednesday, Nov. 4, 2009. Russia and Slovakia have tightened their borders with Ukraine as the World Health Organization began investigating a suspected swine flu outbreak. The European Union says it is coordinating closely with health experts in Ukraine to help it cope with a suspected swine flu outbreak.