The whole world was supposedly “SARS-free.” What those declarations meant, more precisely, was that no SARS infections were currently raging in humans. But the virus hadn’t been eradicated. This was a zoonosis, and no disease scientist could doubt that its causal agent still lurked within one or more reservoir hosts—the palm civet, the raccoon dog, or whatever—in Guangdong and maybe elsewhere too. People celebrated the end of the outbreak, but those best informed celebrated most guardedly. SARS-CoV wasn’t gone, it was only hiding. It could return.
