In 1969, a doctor at a Yale University lab in New Haven, Connecticut, who was studying Lassa fever came down with it. He survived, but, more alarmingly, a technician in a nearby lab, with no direct exposure, also contracted the disease and died.
1969年，设在康涅狄格州纽黑文的耶鲁大学实验室里的一名医生在研究拉沙热的过程中倒下了，然而他活了下来。但更加令人吃惊的是，附近有个实验室的一名技术人员虽然没有直接接触病毒，但也感染上了那种疾病，他死了。
Happily the outbreak stopped there, but we can't count on such good fortune always. Our lifestyles invite epidemics. Air travel makes it possible to spread infectious agents across the planet with amazing ease. An ebola virus could begin the day in, say, Benin, and finish it in New York or Hamburg or Nairobi, or all three. It means also that medical authorities increasingly need to be acquainted with pretty much every malady that exists everywhere, but of course they are not.
幸亏这次爆发就到此为止，但我们不能指望老是那么运气。我们的生活方式招致传染病。空中旅行使传染病病原体轻而易举地在全球传播成为可能。比如说一个伊波拉病毒传染病病原体可以在一天内从非洲贝宁启程，最后抵达纽约，或汉堡，或肯尼亚内罗华，或同时三个地方。这还意味着，医疗当局需要非常熟悉存在于每个地方的每一种疾病，但这当然是不可能的。

In 1990, a Nigerian living in Chicago was exposed to Lassa fever on a visit to his homeland, but didn't develop symptoms until he had returned to the United States. He died in a Chicago hospital without diagnosis and without anyone taking any special precautions in treating him, unaware that he had one of the most lethal and infectious diseases on the planet. Miraculously, no one else was infected. We may not be so lucky next time.
1990年，一个家住芝加哥的尼日利亚人在访问故乡的过程中接触了拉沙热，但是回到美国以后才出现症状。他未经诊断就死在一家芝加哥的医院里。在治疗他的过程中，谁也没有采取防预性措施，因为谁也不知道他患的是世界上最致命、最容易传染的一种疾病。令人称奇的是，别人都没有感染。下一次我们也许不会那样去运了。
And on that sobering note, it's time to return to the world of the visibly living.
说到这里，我们的话题该回到可见生物的世界来了。