Phase 4 - What Does it Mean

The World Health Organization moved to phase 4 today. So what does that mean?

Well, in addition to what has already been posted here and here this article from the Canadian Chronicle Herald does a fine job of describing the situation. Once again, no need to panic but worth keeping an eye on and taking basic precautions that include washing hands. Of course we should do this anyway with all illnesses (but usually don't). H/T AFluDiary

...``A pandemic is not considered inevitable at this time,'' Fukuda said in a late evening press conference in Geneva.

The committee concluded there is definitely person-to-person spread of the virus, but felt it wanted more information about how capable the virus is at continuing to spread through generations of human hosts.

If the WHO saw a widespread community outbreak, he said, the committee would be reconvened and a decision likely made to go to Phase 5. Phase 6 is a pandemic.

``It's fair to say that the move from Phase 3 to Phase 4 signifies that we have taken a significant step closer but ... we are not there yet,'' said Fukuda, a leading influenza expert.

Influenza viruses are notoriously unpredictable. When asked about how the outbreak might evolve, Fukuda painted a picture containing a surprisingly wide range of options, given how quickly this outbreak has unfolded.

The world first learned of the existence of this unusual virus and that it had infected a human on April 17. Less than two weeks later infections have been found in Mexico, the United States, Canada, Spain and Scotland and experts expect it to be found elsewhere soon.
Mexico has linked upwards of 100 deaths to swine flu infection. The U.S. has diagnosed 40 cases, Canada six, Spain one and Scotland two. No country outside of Mexico has yet seen severe disease caused by the virus.

``It is possible that we could stay in Phase 4 for quite a long time. It is possible that as the situation evolves over the next few days, it could evolve to the point where it appears that we have moved into Phase 5. And it is also possible that the disease situation could be quieter and we could move backwards to Phase 3.'' ...(more)