A worrying factoid from CNN (courtesy of Chris Blattman):
In each of the four major pandemics since 1889, a spring wave of relatively mild illness was followed by a second wave, a few months later, of a much more virulent disease. This was true in 1889, 1957, 1968 and in the catastrophic flu outbreak of 1918, which sickened an estimated third of the world’s population and killed, conservatively, 50 million people.
As the small print in stockbrokers and pension funds’ ads always tells us (if only we’d listened), the past is not always a guide to the future, but if the swine flu scare wanes over the summer, it would be dangerous to get complacent.