Just A Phase We're Going Through (Revisited)
# 2093
Two years ago last May, the Karo Cluster in Indonesia highlighted some deficiencies in the WHO's Pandemic Alert scale. Many people around the world, looking at an outbreak that killed 7 people, felt that event met the criteria for raising the alert level to Phase IV.
Here is the current WHO Pandemic Alert Scale.
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Karo, it was argued, was evidence of increased human-to-human transmission.
Elevating the alert level would likely trigger a number of prescribed actions, some of which would be expensive and perhaps interfere with trade and travel. Raising the alert to Phase IV could have had serious economic and political ramifications.
In the end, the WHO decided to wait and see if additional clusters appeared, indicating sustained transmission of the virus - and so the alert phase remained unchanged.
Of course, in doing so, they had to carefully parse the definitions of `increased human-to-human transmission'- the criteria for phase IV - in order to remain at phase III. Along the way they admitted that the existing pandemic scale was `ambiguous' and needed revising.
The WHO has now unveiled a new version of the pandemic alert scale at the Kuala Lumpur Conference, although it won't be adopted until later in the year.
While there may be minor changes between now and then, this new scale is expected to be very close to this one, presented at the 3rd annual A&PI summit held in Singapore last month.
(Hat tip to Ironorehopper on Flutrackers for a link to this powerpoint presentation)
Moving to Phase IV, as you can see, will required sustained H-2H transmission - raising the bar considerably.
While this certainly clarifies the meaning of a Phase IV alert (unless we start arguing over the meaning of `sustained'), it could also mean there will be less warning time before the next pandemic starts.
We simply don't know how quickly an outbreak would spread.
In a worst case, rapidly spreading scenario, the change from Level III to Level IV and onto Level V could literally occur over a matter of a few days.
Based on the size of the Phase IV graphic, it is obviously anticipated that we might not linger at that stage for very long. Of course, it is also possible that the next pandemic could be slow out of the starting gate, and we could have weeks or months at phase IV.
There is certainly no perfect scale, and there is no way to satisfy everyone, no matter what the WHO does.
All in all, I see this scale as being an improvement over the old one, in that it is less ambiguous. Whether it will serve us well is something we won't know until the next pandemic begins.
I know it won't satisfy those who believe that the WHO has `changed the rules in mid game', but sometimes, when something isn't working well, you just have to try to fix it.
Here is how Todayonline is covering the story.
WHO’s six-step proposal offers greater clarity infight against flu infection
Tan Hui Leng in Kuala Lumpur
huileng@mediacorp.com.sg
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THE World Health Organisation (WHO) has released details of a new flu pandemic alert system to replace its existing one, which has been criticised for lacking clarity.
Currently, the world is in phase 3 of the alert system, which is defined as “no or very limited human-to-human transmission”. The six-step, three-layer alert system is a ladder going from “low risk of human cases” in phase 1 to “efficient and sustained human-to-human transmission” in phase 6, the pandemic phase.
Last year, a cluster of eight Indonesian family members who were infected through human-to-human H5N1 transmission sparked confusion over WHO’s flu alert level, with some calling for it to be raised to phase 4; that is, “evidence of increased human-to-human transmission”.
WHO’s new system addresses such issues of interpretation with three layers. The first comprises phases 1 to 3 and is defined as “predominantly animal infections; limited transmissibility among people”.
Phase 4 would be “sustained human-to-human transmission of animal or hybrid animal-human influenza virus, able to cause sustained community-level outbreaks that have been verified” — this is when health authorities can consider issues such as rapid containment, discussion of phase changes, and switching to a pandemicvaccine.
Phases 5 and 6 would comprise the “geographical spread” of flu. There is also a post-pandemic phase.
Dr Nahoko Shindo, the medical officer at WHO’s Epidemic and Pandemic Alert and Response department, said the final version of the phases would be available by year’s end. She announced this on Friday during the 13th Congress of Infectious Diseases in Kuala Lumpur.
