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Six Stages of Sickness

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Current H1N1
Pandemic Rating:
Stage 6















The World Health Organization tracks outbreaks in the following six stage to assess the potential for a new global flu outbreak.








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.






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