Discovery of a missing disease spreader

No sooner had a new year begun in 2003 than citizens were seized with panic in Guangdong in south China. Hundreds were suffered from a pneumonia-like strange disease, some of which had been dead. Both Chinese government and Chinese media remained silent all the time as to the risk of a possible epidemic. No one in the rest of the world knew there was any real cause for alarm. But in March, local outbreaks of a mysterious disease were reported in Hong Kong and Southeast Asian countries. The World Health Organization(WHO) issued a global alert. Even then, health authorities could not reveal where the disease had come from. This story at the onset of the Severe Acute Respiratory Syndrome (SARS) outbreak poses an interesting question. Is it possible to discover the presence of a missing disease spreader from the surveillance records on the cases in other regions?