The Centers for Disease Control and Prevention (CDC) define a flu pandemic as a "global disease outbreak," which occurs when a new influenza virus arises to which people have little or no immunity. The last flu pandemic, which occurred in 1968, killed about 34,000 people in the U.S. and 700,000 worldwide.

On Thursday, the CDC released an interim planning guide on how to handle a future flu pandemic. The guide includes a pandemic severity scale. The scale--which many have compared to the hurricane scale--is based on "case fatality ratio," or the numbers of deaths among the ill.

The CDC puts forth guidelines that local governments and communities can follow depending on the severity of an outbreak. It assumes there will be no vaccines in the beginning and insufficient medication for all those infected. Suggestions include isolation and treatment, voluntary quarantine, the closing of schools, and the changing of workplace rules to decrease contact between people.

Links:
PandemicFlu.gov
"Interim Pre-Pandemic Planning Guide" (full CDC report in PDF)

Previously: "1918: La Grippe" (Sarah Janssen's earlier blog entry about the 1918 flu pandemic)