When a disease insinuates itself so potently into the imagination of an era, it is often because it impinges on an anxiety latent within that imagination. AIDS loomed so large on the 1980s in part because this was a generation inherently haunted by its sexuality and freedom; SARS set off a panic about global spread and contagion at a time when globalism and social contagion were issues simmering nervously in the West. Every era casts illness in its own image. Society, like the ultimate psychosomatic patient, matches its medical afflictions to its psychological crises; when a disease touches such a visceral chord, it is often because that chord is already resonating.