WHO Raises Flu Alert Level To Phase 4

MEXICO CITY — Mexico says the World Health Organization has raised its pandemic alert for swine flu by one level, two steps short of declaring a full-blown pandemic

Mexico health department spokesman Carlos Olmos confirms the move.

WHO says the phase 4 alert means sustained human to human transmission causing outbreaks in at least one country. It signals a significant increase in the risk of a global epidemic, but doesn't mean a pandemic is inevitable.

Many experts think it may be impossible to contain a flu virus already spreading in several countries.

WHO has confirmed human cases of swine flu in Mexico, the United States, Canada and Spain. Only Mexico has reported deaths from the new strain.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

GENEVA (AP) _ The World Health Organization says there are now 40 confirmed cases of swine flu in the United States and that it "very concerned" about the disease's spread.

WHO says none of the cases in the U.S. have been fatal.

But the U.N. agency says it could decide in a matter of hours whether to raise its pandemic alert level as a result of the increasing number of confirmed swine flu cases in Mexico and elsewhere.

Spain confirmed the first swine flu case outside North America on Monday.

WHO spokesman Paul Garwood said an emergency meeting is being led Monday by the agency's chief Dr. Margaret Chan.

He said in the Spanish case the disease was transmitted in Mexico and not passed among people in Spain.