Thursday, August 30, 2007

UK: Worst Case Estimates

 

# 1102

 

 

 

Last year, April of 2006 to be precise, the Scotsman Newspaper ran an article on a `secret government report' they'd seen which greatly increased the expected death toll from a pandemic over what had previously been stated. 

 

At the time, the official UK `guesstimate' was that roughly 53,000 deaths would occur during a pandemic. 

 

This secret report supposedly stated a `prudent worst case estimate' was nearer to 320,000 deaths, and an `absolute worst case' of up to 700,000 deaths in the UK.  

 

Today the UK papers are running a story about a newly released government report which matches very closely the details from the Scotsman story of 16 months ago. 

 

 

New flu strain 'could kill 650,000'


By Juliet Turner and agencies

Last Updated: 2:47pm BST 30/08/2007

Up to 650,000 people could die in England and Wales in the event of a flu pandemic, an official report warns.

 

The Home Office document outlines plans for dealing with an outbreak, including the possibility of mass burials and storing dead bodies in refrigerated trailers.

 

Processes for dealing with mass casualties were likely to be overwhelmed at the height of a pandemic, with up to 22pc extra deaths at its height, the paper said.

 

The risk of a human influenza pandemic is different from seasonal flu, which affects the population every winter and plans would only apply if a new strain of "ordinary" flu emerged, or if avian flu became easily transmitted from birds to humans.

 

Officials projected between 48,000 and 650,000 deaths depending on a "base" case scenario and a "worst" case scenario.

 

Even the prudent projections involved 320,000 mortalities from a human flu pandemic.

 

 

A ten-fold increase in the death estimates is, of course, big news.  But is 650,000 deaths a realistic `worst-case' number?

 

With a little more than 60 million residents in the UK, 650,000 deaths is roughly 1 person in 100.   Or 1% of the population. 

 

If 30% of the population contracts the illness (and it could be more), then this assumes a CFR, or case fatality rate, of 3%.  Roughly what we saw in the 1918 pandemic. 

 

Unfortunately there is no reason to believe that 1918 was the worst-case scenario.  With the H5N1 virus currently claiming the lives of 60% of it's victims, calling a 3% fatality rate the `worst-case' requires one heck of a leap of faith that the virus will lose lethality. 

 

In the end, any estimates made now, before a pandemic starts, are pure speculation.   We don't even know what virus will cause the next pandemic.  It could be H5N1, or perhaps one of the H7 viruses currently circulating.  It might even be one that isn't currently on our radar screen.

 

Governments obviously need to come up with some `worst-case' numbers for planning purposes, and using something comparable to the 1918 pandemic isn't unreasonable. 

 

Just as long as we understand that we may not get what we plan for.