fighting pandemic?

Associated Press | Mexico's president assumed new powers Saturday to isolate people infected with a deadly swine flu strain as authorities struggled to contain an outbreak that world health officials warned could become a global epidemic.

New cases of swine flu were confirmed in Kansas and California and suspected in New York City. But officials said they didn't know whether the New York cases were the strain that now has killed up to 81 people in Mexico and likely sickened 1,324 since April 13, according to figures updated late Saturday by Mexico's health secretary.

Tests have confirmed swine flu as the cause of death in 20 of the cases.

Mexican soldiers and health workers patrolled airports and bus stations as they tried to corral people who may be infected with the swine flu, as it became clearer that the government may have been slow to respond to the outbreak in March and early April.

Now, even detaining the ill may not keep the strain — a combination of swine, bird and human influenza that people may have no natural immunity to — from spreading, epidemiologists say.

The World Health Organization on Saturday asked countries around the world to step up reporting and surveillance of the disease and implement a coordinated response to contain it.