Mexico's health minister said there had been just 26 confirmed cases, including seven deaths, of swine flu in the country, although the virus is suspected to be behind 159 deaths in the Central American country.
Swinefighter's popularity has come on the back of the global panic. The game gives players the task of wiping out the virus because it has "gotten out of control."
The player is a doctor with a huge needle who in 20 seconds needs to inject as many smiling green pigs as possible before they fly off to infect different countries. If the doctor successfully inoculates the green pig, then it oinks, turns pink and disappears. The winner is the one who is able to wipe out as many green flying pigs in the time.
The game also gives health advice to players, including hygiene recommendations.
Sixty-four cases of human swine flu infection have been confirmed in the United States and 13 in Canada, although there have been no fatalities. The United States has declared a public health emergency.
In Europe, swine flu cases have been confirmed in Spain, Germany and the U.K. Suspected infections have been reported in New Zealand, Israel, Brazil and Australia.
Countries around the world have begun measures to prevent a swine flu pandemic.
The World Health Organization has raised the level of swine flu pandemic alert from phase 3 to 4, implying a significant risk increase, two steps short of a full pandemic.
All restaurants and cafes were shut down in Mexico City on Tuesday until May 6 as part of measures to prevent the spread. The closures are expected to result in losses for restaurant and cafe owners of $10 million, the National Restaurant Association said.
