by Merry Youle — When you read the ti­tle – 'The Great Epi­demic' – what came to mind? The Black Death (Yersinia pestis) that in two years killed 20 mil­lion peo­ple in Eu­rope – ap­prox­i­mately 30–60% of the pop­u­la­tion? The 1918 flu pan­demic with its tally of 50 mil­lion dead in three years? AIDS, with a death toll...