Tourists wearing masks drink beer in downtown Mexico City, capital of Mexico, April 25, 2009. Of the 81 deaths suspected of being caused by swine influenza in Mexico, 20 are confirmed. More than 1,300 people in Mexico were suspected to be infected with the flu.

A boy wearing a mask sells candy at a restaurant in downtown Mexico City, capital of Mexico, April 25, 2009.

A medical staff measures body temperature of a man who prepares to enter the downtown areas of Mexico City, capital of Mexico, April 25, 2009.

A medical staff takes an oral examination for a woman who prepares to enter the downtown areas of Mexico City, capital of Mexico, April 25, 2009.