120 million deaths from swine flu

On Monday 27th April 2009, there was speculation about the possibility of a swine ‘flu pandemic resulting from spread of the H1N1 virus from an outbreak in Mexico. Metro led with “Pandemic could kill up to 120m, warn experts”.

Can the UK’s Health Protection Agency throw any light on where this figure comes from? No. Is it covered in the latest information from the US Centers for Disease Control and Prevention (which is reviewing the current cases together with the WHO)? No.

The figure seems to come from making one the following two calculations: 1) If 2% of the people who might have been infected by H1N1 in Mexico have died (which is possible but not established), then 2% of the world’s population is 120 million, so if everyone in the world caught it, 120 million could die. There has never been a disease caught by everyone in the world. 2) If we take the figures from the “Spanish Flu” of 1918 (50 million deaths) and scale them by the increase in world population (4 times larger now), it produces a figure of about 200 million deaths. This speculative projection assumes that the Mexican H1N1 virus is as aggressive, that healthcare, surveillance and medicine are the same as in 1918 and that the world population is in the same state of health as in 1918. There is no evidence to support these assumptions.

The WHO is yet to report on how many of the alleged infections are H1N1, how many of these have died, whether a similar mortality rate is then likely if it spreads, how many of the cases were spread human to human, rather than animal to human, and whether it is likely to spread.

For further, up-to-date information please visit the World Health Organisation’s website here .

    Last updated: April 28 2009