Friday, November 23, 2007

Variations On A Theme



# 1282


When you strive to prepare for a disaster, it is generally prudent to plan for a worst-case scenario.  No, you can't always predict how bad an event will be, but you can, based on past histories and current trends, make educated guesses. 



For the past couple of years government agencies have been adamant that a worst-case pandemic scenario would involve an attack rate of 25%-30%, absenteeism rates of up to 40%, and a CFR (Case fatality ratio) of 2.5%.  


Roughly what the United States saw in the 1918 Spanish Flu.


Officially, for many nations, that's the `worst-case scenario'.    Anything more is, frankly, `unthinkable'.


Amazingly, here in the United States, it has been left up to each state to decide what their `worst-case scenario' would be, and that is what they are planning for.  


Some states, like South Carolina, have decided to plan for a far lesser event than the Federal Government.  Their assumptions are for something akin to the 1957 Asian Flu.   This is from their State's Pandemic Preparedness web site.


It is impossible to accurately predict what effect a pandemic would have on South Carolina. Experts believe 15% to 40% of the state’s population could be infected in the first wave of the illness. Also, hospitals and physicians’ offices could expect to see many more patients than normal. There is no way to know how many of those cases would be severe or deadly. However, it is almost certain that more people would die during a pandemic than during the usual seasonal outbreaks of human influenza.


South Carolina could experience approximately 3,600 deaths due to complications affecting a greater number of people.


With a population of around 4 million, the federal assumptions of a 25% attack rate and a 2.5% CFR would generate 25,000 deaths in South Carolina. The `worst-case' South Carolina is publicly willing to consider is 1/7th as bad as the Federal assumptions.


And that is a recipe for disaster.


Even in states where planners assume a `1918 scenario', preparations lag. 


In Florida, the legislature failed to approve funds to purchase Tamiflu under the Federal Stockpiling plan.   Right now, should a pandemic erupt, Florida would be entirely dependent upon receiving their share of the Federal stockpile, and would have only enough Tamiflu for about 12% of their residents.


A far cry from the UK, where their government is procuring enough Tamiflu for 50% of their population.


If we see a severe pandemic, your survival, and the survival of your family, could well be determined by where you live.


Nations, and states within nations, that prepare for a severe pandemic are likely to suffer fewer casualties than those that fail to prepare adequately.   


A few notable scientists, along with a handful of bloggers, have tried to raise awareness of the possibility of a worse-than-1918 case scenario.  Few governments will even consider that.


While we cannot know what the next pandemic will bring, or even what virus will be the causative agent, we do know the H5N1 virus currently kills 60% of all reported patients.   And that should be a sobering warning.


Right now, the UK's decision to double their stockpile of Tamiflu is leading the news.   They are also procuring 35 Million N95 respirators and 350 million surgical masks, and are looking seriously at pre-pandemic vaccine options.    Instead of a 25% attack rate, they are assuming that 50% of their population could be stricken.


So far, however, they are still looking at a 2.5% CFR.    With up to 30 million people stricken in the UK, that would mean as many as 750,000 could die.   A horrific number.


The United States, on the other hand, hasn't adjusted their assumptions upward as the UK has.  We are still working on a 25% attack rate and a 2.5% CFR.   We're we to adopt the UK assumptions, our estimates of up to 2 million deaths would be doubled.


While the US and the UK won't publicly entertain the notion of a higher CFR, scientists in other countries aren't so reticent.   Dimitri Lvov of Russia's Institute of Virology has spoken of 1 billion deaths worldwide from a pandemic, and from Norway we get this story (Translation courtesy of Urdar on Flu Wiki).




Norwegian scientist and member of national pandemic committee Olav Albert Christophersen is critisising government for underestimating the danger.

"Spanish flu" is not considered worst case scenario anymore, It could be much worse, half the population could die based on what we know about H5N1 in Indonesia and Egypt. The plans must be based on this, and not a milder scenario than Spanish flu. We now have airtransport and huge city populations, this will make things worse.

He is cowriter on a report with John Fredrik Moxnes, scientist at the Defence institute of science to be published in "Microbial Ecology in Health and Disease".


I've no idea how bad the next pandemic will be.  Despite all of the statements and assumptions, no one does.   The next pandemic might not even stem from the H5N1 virus.    We could see a repeat of 1968 or 1957. 


Or we could see an event that makes 1918 seem mild in comparison.


But even if we see an event no worse than the Spanish Flu of 1918, with many nations and states failing to prepare for even that level of a disaster, I can make one prediction with a high level of confidence.


After it's over, for those officials who failed to take preparations seriously,  there will be hell to pay.

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