Mystery Microbes in a City’s Subway
城市地鐵的神秘微生物
By Elizabeth A. Harris

Have you ever been on the subway and seen something that you did not quite recognize, something mysteriously unidentifiable?
你搭地鐵時是否曾看過某個你不大認得出，某個神祕到無法辨識的東西？

Well, there is a good chance scientists do not know what it is either.
唔，很有可能科學家也不知道是甚麼東西。

Researchers at Weill Cornell Medical College in New York released a study recently that mapped DNA found in New York’s subway system – a largely subterranean behemoth that carries 5.5 million riders on an average weekday, and is filled with hundreds of species of bacteria (mostly harmless), the occasional spot of bubonic plague, and a universe of enigmas. Almost half of the DNA found did not match any known organism and just 0.2 percent matched the human genome.
紐約康乃爾大學威爾醫學院的研究人員最近發表一項研究，他們繪製了紐約地鐵系統的DNA圖譜。這個地下龐然大物每個工作日平均運送550萬名乘客，充滿數以百計種細菌（大多無害），偶爾還有淋巴腺鼠疫，這是個謎一般的世界。在紐約地鐵系統中發現的DNA，近半數與任何已知的有機體都不匹配，只有0.2%與人類的基因組相符。

“People don’t look at a subway pole and think, ‘It’s teeming with life,’ ” said Dr. Christopher E. Mason, a geneticist and the lead author of the study. “After this study, they may. But I want them to think of it the same way you’d look at a rain forest, and be almost in awe and wonder, effectively, that there are all these species present – and that you’ve been healthy all along.”
「人們注視地鐵上的扶手柱，原本不會心想，『這上面滿是生命，』」研究主要作者、康乃爾大學威爾醫學院遺傳學家克里斯多夫．梅森表示：「這項研究發表後，人們可能會開始這樣想。但是我想讓人們以看待雨林的眼光看待地鐵，這裡有這麼多物種，而且沒有影響你的健康，令人讚嘆。」

Dr. Mason said the inspiration for the study struck about four years ago when he was dropping off his daughter at day care. He watched her explore her new surroundings by happily popping objects into her mouth. As is the custom among tiny children, friendships were made on the floor, by passing back and forth toys that made their way from one mouth to the next.
梅森說，這項研究的靈感大約來自四年前，當時他把女兒送去日托中心。他看見女兒探索新環境的方式是高興地把東西放進嘴裡。幼童的友誼都是在地板上建立起來的，來回交換玩具，你啃完我啃。

“I couldn’t help thinking, ‘How much is being transferred, and on which kinds of things?’ ” Dr. Mason said. So he considered a place where adults can get a little too close to each other, the subway.
「我忍不住想，『他們之間究竟傳遞了多少東西，傳遞了哪些東西？』」梅森說。所以他想到了一個成年人可能彼此靠得太近的地方：地鐵。

Thus was the project, called PathoMap, born. Over the past 17 months, a team of students and volunteers collected DNA from benches, handrails, seats, doors, poles and turnstiles.
這個被稱為PathoMap的研究計畫就此誕生。在過去的17個月中，學生和志工組成的團隊從長凳、樓梯扶手、座位、車門、柱子和旋轉門採集DNA。

In addition to the wealth of mystery DNA, the study’s other findings reflected New York’s famed diversity.
除了大量的神祕DNA，這項研究的其他發現還反映出紐約著名的多樣性。

Dr. Mason said that the DNA found in some subway stations match the neighborhood’s demographic profile. An area with a high concentration of Hispanic residents near Chinatown in Manhattan yielded a large amount of Hispanic and Asian genes.
梅森說，在某些地鐵站找到的DNA與其周圍的人口狀況相符。曼哈坦中國城附近有個拉美裔密集聚居區，該處地鐵站裡就有大量拉美和亞洲的基因。

Live, antibiotic-resistant bacteria were discovered in 27 percent of the samples. Three samples were associated with bubonic plague and two with DNA fragments of anthrax, though none showed evidence of being alive.
研究還發現，在收集到的樣本中，27%是活性抗藥性菌。三個樣本與淋巴腺鼠疫有關，兩個樣本有炭疽病的DNA片段，這些樣本都沒有活性。

The presence of anthrax, Dr. Mason said, “is consistent with the many documented cases of anthrax in livestock in New York State.”
梅森說，發現炭疽病樣本「與紐約州牲口染病的許多病例吻合。」

The city’s health department called the study “deeply flawed,” and misleading, but Dr. Mason said, “Our findings indicate a normal, healthy microbiome.”
市府衛生部門形容這項研究「有嚴重瑕疵」、「誤導民眾」，但梅森說：「我們的發現展示了一個正常、健康的微生物群。」

Kevin Ortiz, a spokesman for the Metropolitan Transportation Authority, said in an email that the study found microbes “at levels that pose absolutely no danger to human life and health.”
紐約大都會運輸署發言人凱文．歐提斯透過電子郵件表示，研究發現的微生物「其密度對人類生命和健康毫無危害。」

http://www.nytimes.com/2015/02/06/nyregion/among-the-new-york-city-subways-millions-of-riders-a-study-finds-many-mystery-microbes.html

紐約時報中文版翻譯：
http://cn.nytimes.com/science/zh-hant/

2015-02-24聯合報/G5版/UNITED DAILY NEWS 張佑生譯 原文參見紐時週報十版下