How the World Health Org. measures a pandemic

Tools

By Associated Press

The World Health Organization has six phases of pandemic alert to assess the potential for a new global flu outbreak. If the World Health Organization raises its pandemic alert level to 4 or 5, that signals that the swine flu virus is becoming increasingly adept at spreading between humans. The WHO raised the alert level to 4 on Monday.

  • Phase 1. There are no viruses circulating in animals that have been reported to cause infections in humans.
     
  • Phase 2. An animal flu virus has caused infections in humans in the past and is considered to be a potential pandemic threat.
     
  • Phase 3. An animal or mixed animal-human virus has caused occasional cases or small clusters of disease, but the virus does not spread easily.
     
  • Phase 4. The new virus can cause sustained outbreaks and is adapting itself to human spread.
     
  • Phase 5. The virus has spread into at least two countries and is causing even bigger outbreaks.
     
  • Phase 6. More outbreaks in at least two regions of the world; the pandemic is under way.

With an elevated pandemic alert level, WHO might also issue travel advisories, warning against nonessential travel to regions battling outbreaks, trade restrictions, the cancellation of public events or border closures.

During the SARS outbreak in 2003, WHO travel advisories drastically slashed travel to affected regions, curtailing the outbreak.

(Copyright 2009 The Associated Press.)
 

Most Popular

Icon
Current Temp 46.0 °F
Overcast
More Weather

Breaking News Blog

July 2014 summer heat

How hot is too hot for you?

  • Anything over 100
  • When it hits the 90s
  • Under 80 is A-OK
  • Bring it on!

Your Photos