Governments around the world are taking steps to stop the spread of the new strain of swine flu that's thouht to have killed nearly 150 people in Mexico and has infected people in a number of other countries. The World Health Organization has raised the level of its pandemic alert for the virus, indicating that the risk of a global outbreak is high. But it says it is NOT recommending either travel restrictions or border closures. In Mexico city, public life has all but ceased as residents follow government orders to stay home.