World Health Organization calls swine flu outbreak a pandemic

The World Health Organization has declared the seven-week-old outbreak of the novel H1N1 influenza virus a pandemic. The announcement essentially warns the WHO's 194 member nations to get ready for the new flu strain, which is likely to infect as much as one-third of the population in the first wave and return in later waves that may be more severe. The declaration does not by itself initiate any particular action, nor does it predict the pandemic's ultimate severity, which is likely to vary between regions, ages, ethnic groups, and economic strata.