|This diary is inspired by lugon, who said yesterday that he refuses to call any pandemic `mild'. Let's see if you agree with him.
I'm going to take the lowest end of the figures used in the UK pandemic plans, 25% AR occurring over the first wave and 0.4% CFR, and see what this means for a city like London.
Inner London has a population of 7.4M (National Statistics 2004). A pandemic with 25% AR and 0.4% CFR would mean 7400 deaths over a 15 week period (still using figures from UK plans).
The last mass casualty event that happened in London was the bombings in the London Underground on 7 July 2005 which killed 52 people. 7400 deaths would be the equivalent of 142 bombings, happening over a 15 week period, or just under 10 a week.
Of course, in reality these deaths would not be evenly distributed over 15 weeks, but more-or-less follow the epidemic curve, such that the weekly rate of accumulation of deaths would look something like this: 7, 22, 81, 310, 1095, 2694 and so on.
As you look at those figures, at which point do you think the people of London will stop going to work to avoid infection? At which point would parents pull their kids out of school? At which point would supplies run out because too many people did not turn up for work while at the same time everyone is buying more in anticipation of shortages? At which point would the public start blaming the government for failing to warn them?
At which point would looting (of closed shops), rioting, or at least general vandalism happen?
At which point would the London Stock Exchange suspend trading because of staff absences, extreme volatility of trading, failures in payment systems, or grid failure?
Let's look at the impact on health services. Still using this same scenario, at the peak 2 weeks (weeks 6 & 7), there would be approximately 1600 people dying per week, which is the equivalent of 31 London bombings per week or 4.5 per day. Can the health services deal with an emergency where the number of deaths is 4 ½ times that of the last mass casualty event, except that it's happening day after day, and at a time when the staff sickness rate would have at least equaled if not surpassed the attack rate of the general population, assuming none of them have gone AWOL?
Now let's take a look at what such a pandemic would mean at a global level. 25% AR and 0.4% CFR for 6.6 billion people works out at 6.6 million deaths. The last biggest mass casualty event globally was the tsunami in December 2004, which killed 280,000 people. Assuming it takes about 6 months for the first wave to cover all parts of the world, 6.6 million deaths is the equivalent of 24 tsunamis over that period, or 4 tsunamis per month each covering a region the size of say 3-4 countries the size of UK.
About 2.9 million people died of AIDS in 2006, of which 2.1 million occurred in sub-Saharan Africa. The devastation to this region is profound, but has had minimal effect on the rest of the world because this is one of the poorest regions in the world and it's share of global trade is minuscule. But influenza is a very different disease; it can devastate rich as well as poor countries. If the next pandemic, as with previous ones, exhibits variations in severity in different parts of the world, what are the chances that those cities that are faring a lot worse than London (described above) would include at least some of the ports crucial for world shipping, such as Hong Kong (world rank #1), Vancouver (Canada rank #1), Long Beach, CA (US rank #5), or Rotterdam (world rank #2)?
There is no such thing as a mild (unmitigated) pandemic.