WHO: H1N1 officially a pandemic

GENEVA, Switzerland The H1N1 influenza, popularly known as swine flu, is officially a pandemic.

The World Health Organization declared the first global flu pandemic since 1968 on Thursday, upgrading its warning level from five to six as the flu spreads in the Southern Hemisphere, which is approaching its winter season as the Northern Hemisphere approaches its summer.

As of Wednesday, the virus had been reported in 74 countries, with more than 27,700 infections and 141 deaths. On Friday, the Centers for Disease Control and Prevention reported 13,217 cases in the United States and 27 deaths.

Health experts have said that the severity of the flu thus far appears moderate, though it has persisted in the Northern Hemisphere even as the seasonal flu dies off, and they fear that it could reemerge in the coming winter in deadlier form.