A man wearing a face mask waves a flag during May Day protests in Mexico City's main square Zocalo May 1, 2009. Mexican President Felipe Calderon has asked Mexicans to stay home from May 1 to 5 and ordered them to cancel May Day parades and religious processions to help slow the spread of influenza A (H1N1), formerly referred to as swine flu.
REUTERS/Eliana Aponte (MEXICO HEALTH POLITICS CONFLICT)