The WHO hasn't yet declared an official pandemic. If that happens, world vaccine production would lag only four to six months behind, says Marie-Paule Kieny, PhD, the World Health Organization director of the Initiative for Vaccine Research. Get the Facts Get the latest swine flu information from and the CDC, plus other facts you need to know. But given the growing number of cases worldwide -- as of 1,658 confirmed cases in 23 nations -- acting CDC Director Baily Besser, MD, says it would be surprising if an official pandemic was not eventually announced.

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CDC Swine Flu Updates State-by-State Information World Health Organization What People Are Asking Our experts answer your swine flu questions. Swine Flu Slideshow Like people, pigs can get influenza (flu), but swine flu viruses aren't the same as human flu viruses. Swine Flu Precautions Swine Flu Symptoms What Is a Pandemic.

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