国家地理:The Silent Stalker 安静的捕杀者（在线收听） |
| Under the influence of rabies, even docile animals often become dangerously aggressive and bite without provocation. Since the virus often concentrates in the saliva of the infected animal, a single bite can pass it on directly into the blood of the victim. Even a family dog or cat can become a furious agent of death. But no one in Hatumalino had seen any trace of a ferocious animal, wild or domestic. Neither Margery nor Emerson reported any attack. Their bodies showed no evidence of bite wounds. How did they get infected? The autopsy revealed a clue, a particular type of rabies virus. In addition to classic rabies, there is another less common form of the virus, called dumb rabies. It has a distinct set of symptoms and they match the children's exactly. This was the virus found in Margery's brain. Different species of animals carry different strains of rabies. Near Hatumalino, there is only one creature known to carry dumb rabies that's stealthy enough to bite into living flesh without alerting its prey, a creature that lives in legends and nightmares----the vampire bat. Vampire bats are unique to Latin America but they are famous worldwide for their gruesome diet, fresh, flowing blood. The bats have specialized teeth, look like an armor so they can be kept razor-sharp and project forward for easy cutting. With incredible precision, the vampire makes a small slice in the victim's skin usually while it sleeps. Most never feel a thing. This might explain why Emerson and Margery never knew they had been bitten. The bat then uses its abrasive tongue to lap up the blood that flows from the wound. Its saliva contains agents to keep the blood flowing freely. Spit and blood often mingle for 25 minutes during a meal. And if the feeding bat has active rabies, it is almost guaranteed that its host will contract the disease. |
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