陽光能殺死病毒嗎?乘電梯有多危險?

陽光能殺死病毒嗎?乘電梯有多危險?

Can sunlight kill the coronavirus? What about UV light?

陽光能殺死冠狀病毒嗎?紫外線呢?

Sunlight contains three types of ultraviolet light – UVA, which tans your skin (and ages it) and can cause eye damage; UVB, which burns and also ages skin; and UVC, which is "the most harmful one" because it's quite good at destroying genetic material, explains Juan Leon, a virologist who focuses on environmental health at Emory University.

陽光中含有三種紫外線——長波紫外線(UVA)，它會使你的皮膚曬黑(并使其老化)，還會造成眼睛損傷;中波紫外線(UVB)，會灼傷皮膚，也會使皮膚老化;短波紫外線(UVC)是“最有害的”，因為它很擅長破壞遺傳物質(zhì)。埃默里大學研究環(huán)境健康的病毒學家胡安•萊昂解釋說。

Luckily, he notes, the sun's UVC rays don't reach us because they are filtered out by Earth's atmosphere.

幸運的是，他指出，太陽的短波紫外線照射不到我們，因為它們被地球的大氣層過濾掉了。

Sunlight can be a good disinfectant with other pathogens. Leon notes that's why in the developing world, the World Health Organization recommends sterilizing water by putting it in plastic containers and leaving it outside in the sun for about 5 hours.

陽光對其他病原體來說是很好的消毒劑。萊昂指出，這就是為什么在發(fā)展中國家，世界衛(wèi)生組織建議把水放在塑料容器中消毒，并在陽光下放置約5個小時。

"Right now, there is no data on whether the UVA rays of the sun can inactivate this coronavirus," says Leon. However, research on SARS, another coronavirus closely related to the one causing the current pandemic, found that exposing that virus to UVA light for 15 minutes did nothing to reduce its infectivity, Leon says.

萊昂說:“目前，還沒有關于太陽的UVA射線是否能滅活這種冠狀病毒的數(shù)據(jù)。”然而，另一種與引起當前大流行密切相關的冠狀病毒SARS的研究發(fā)現(xiàn)，將該病毒暴露在UVA光下15分鐘并沒有減少其傳染性，萊昂說。

The results with UVC light were more promising, notes virologist Julia Silva Sobolik, a researcher in Leon's lab at Emory. "UVC for longer durations, over 15 minutes, was found to be more effective at inactivating SARS," she says.

埃默里利昂實驗室的研究人員、病毒學家茱莉亞·席爾瓦·索博利克指出，用UVC照射的結果更有希望。”她說：“我們發(fā)現(xiàn)，持續(xù)時間超過15分鐘的UVC在滅活SARS方面更有效。”。

In fact, UVC light is frequently used to sterilize equipment in medical settings, says Leon.

事實上，UVC光經(jīng)常用于醫(yī)療設備的消毒，萊昂說。

If I step into an elevator where an infected person has recently been, could I get the virus?

如果我走進一個最近有感染者呆過的電梯，我會感染病毒嗎?

Perhaps you live in a building with an elevator, you ride in one at work or you use one at the grocery store with a full cart. Maybe you're facing an empty elevator and are worried. Could a person with COVID-19 have just been in that space. Should you worry about viral particles in the air?

也許你住在有電梯的大樓里，你在工作的時候乘坐電梯，或者你在雜貨店推著滿滿一車的車使用電梯。也許你正面對著一個空蕩蕩的電梯，你很擔心。有沒有一個攜帶COVID-19的人剛剛在那個地方呆過。你應該擔心空氣中的病毒顆粒嗎?

The Centers for Disease Control and Prevention says current data suggest that the primary mode of transmission is through respiratory droplets from an infected person that can land in the mouths, noses or eyes of people who are nearby or possibly be inhaled into the lungs of those within close proximity.

疾病控制和預防中心說，目前的數(shù)據(jù)表明，主要的傳播方式是通過受感染者的呼吸飛沫，這些飛沫可以落在附近的人的口、鼻或眼睛中，或者可能被吸入到附近人的肺中。

The virus is also believed to spread by touching a contaminated surface and then touching your eyes, nose or mouth.

這種病毒也被認為是通過接觸被污染的表面，然后再接觸你的眼睛、鼻子或嘴巴來傳播的。

What about smaller viral particles in the air? The CDC says the role of "small respirable particles, sometimes called aerosols or droplet nuclei, to close proximity transmission is currently uncertain. However, airborne transmission from person-to-person over long distances is unlikely."

空氣中較小的病毒顆粒呢?疾控中心說，“小的可吸入顆粒物，有時稱為氣溶膠或液滴核，對近距離傳播的作用目前還不確定。然而，遠距離的人與人之間的空中傳播是不太可能的。”

As NPR's Nell Greenfieldboyce has reported, the question of how the virus moves through the air is something scientists are still trying to understand — and disagree about. Even if traces of the virus can be found in the air if an infected person breathes or speaks, it's not clear that the concentration is high enough to transmit the virus.

據(jù)NPR新聞的內(nèi)爾·格林菲爾德·博伊斯報道，關于病毒如何在空氣中傳播的問題，科學家們?nèi)栽谂斫?，但仍存在分歧。即使在感染者呼吸或說話時可以在空氣中發(fā)現(xiàn)病毒的痕跡，也不清楚其濃度是否高到足以傳播病毒。

Linsey Marr is an aerosol scientist at Virginia Tech, and she believes that transmission by inhalation of virus in the air is happening.

琳瑟·瑪麗是弗吉尼亞理工大學的一位氣溶膠科學家，她相信通過吸入空氣中的病毒傳播正在發(fā)生。

"I would be concerned about elevators because they are a confined space," she said in an email interview with NPR. "Many elevators do not seem to have mechanical ventilation, like a fan, beyond the natural ventilation that occurs when the doors open and close."

“我會擔心電梯，因為它們是一個封閉的空間，”她在接受美國國家公共電臺(NPR)的電子郵件采訪時說。“除了門開關門時的自然通風，許多電梯似乎沒有像風扇那樣的機械通風。”

The main thing to watch out for is the surfaces on the elevator: especially the buttons.

主要注意的是電梯的表面，尤其是按鈕。