新的冠狀病毒是否悄無聲息地傳播?

新的冠狀病毒是否悄無聲息地傳播?

Public health officials attempting to contain the new coronavirus are trying to figure out how easily it spreads. One key question is whether people who are infected but show no symptoms can infect other people.

試圖控制這種新型冠狀病毒的公共衛(wèi)生官員正在試圖找出它傳播的容易程度。一個關鍵問題是，被感染但沒有表現(xiàn)出癥狀的人是否會傳染給其他人。

"If you have a lot of people who [have mild disease or are] asymptomatic and not seeking medical care for respiratory illness but are still contagious, you're going to have a very difficult time," says Jeffrey Shaman, a professor of environmental health sciences at Columbia University.

哥倫比亞大學的環(huán)境健康科學教授杰弗里•沙曼表示:“如果有很多人(患有輕度疾病或無癥狀)，沒有尋求治療呼吸系統(tǒng)疾病的醫(yī)療服務，但仍然具有傳染性，那么你將面臨非常艱難的時期。”

Two previous deadly outbreaks of coronavirus – SARS and MERS – only spread from people who were showing symptoms of disease.

以前兩次致命的冠狀病毒爆發(fā)——非典和中東呼吸綜合征——只從有疾病癥狀的人身上傳播。

But Shaman has looked at more common coronaviruses, in particular four other coronaviruses that usually don't cause anything more serious than a cold. He's found many people shed those viruses even when they report no symptoms at all. (His results are not peer-reviewed but are available as a preprint).

但沙曼研究了更常見的冠狀病毒，特別是其他四種冠狀病毒，它們通常不會引起比感冒更嚴重的癥狀。他發(fā)現(xiàn)許多人即使在完全沒有癥狀的情況下也會感染這些病毒。(他的研究結果沒有經過同行評審，但可以作為預印本獲得)。

His study found the coronavirus in the nasal passages of people who didn't report any symptoms, "and it's going to leak out as they're speaking and breathing and coughing and sneezing and wiping their nose," Shaman says.

他的研究發(fā)現(xiàn)，冠狀病毒存在于那些沒有報告任何癥狀的人的鼻腔通道中，“當他們說話、呼吸、咳嗽、打噴嚏和擦鼻涕時，病毒就會泄露出來，”沙曼說。

"Whether it's ... a sufficient quantity to make somebody else infectious, we can't discern that from what we've done."

“它是否…足以讓其他人傳染，我們無法從我們的所作所為中看出這一點。”

Likewise, it's hard to know what's up with the novel coronavirus. Scientists in Germany reported a case in the New England Journal of Medicine on Jan. 30 in which a visitor from China without symptoms passed the disease along to a colleague in Munich. But, as Science magazine first reported, that was wrong.

同樣，我們也很難知道新型冠狀病毒是怎么回事。1月30日，德國科學家在《新英格蘭醫(yī)學雜志》上報道了一起病例，一名沒有癥狀的中國游客將病毒傳染給了慕尼黑的一位同事。但是，正如《科學》雜志最初報道的那樣，這是錯誤的。

The woman actually did have symptoms.

這個女人確實有癥狀。

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, had cited that case last week at a White House meeting in which health officials announced a quarantine for people returning from the disease's hotspot in China. He says the errant letter in the journal doesn't alter his view.

美國國家過敏與傳染病研究所所長安東尼·福奇博士上周在白宮的一次會議上提到了這一病例。衛(wèi)生官員在會上宣布，將對從中國這一疾病高發(fā)地區(qū)回來的人進行隔離。他說，雜志上那封錯誤的信并沒有改變他的觀點。

Fauci says he's been talking to trusted colleagues in China about this issue, and "they told me without a doubt there is some degree of asymptomatic transmission."

福奇說，他一直在與他信任的中國同事討論這個問題，“他們毫無疑問地告訴我，存在某種程度的無癥狀傳播。”

But he says to the extent it's happening, it doesn't explain the apparently explosive spread of this disease within China.

但他說，就目前的情況來看，這并不能解釋這種疾病在中國的爆炸性傳播。

The history of respiratory disease is that "asymptomatic transmission is not the main driver of [any] outbreak."

呼吸道疾病的歷史表明，“無癥狀傳播并不是(任何)疫情爆發(fā)的主要原因。”

Even so, Maria van Kerkhove at the World Health Organization says this question is subject of intense scrutiny right now.

即便如此，世界衛(wèi)生組織的瑪麗亞·范·科霍夫表示，這個問題目前正受到密切關注。