(单词翻译:单击)
Good news. It looks like we've finally made it through this nasty flu season.
好消息。我们终于熬过了这个讨厌的流感季。
Hopefully, thanks to a flu shot and lots of hand-washing, you managed to avoid getting sick.
多亏了流感疫苗和勤洗手，让大家成功避免流感。
Maybe you even went the extra mile this year and put on a surgical mask to ward off germs in crowded, public places.
或许你甚至还戴上了医用口罩阻隔拥堵人群中的细菌。
After all, according to public wisdom, that totally works, right? Well, it's not that simple.
毕竟，公众的智慧称，这样完全有效，对不？好吧，其实没那么简单。
That fetching paper mask might not have actually prevented you from catching the flu --
那种纸面罩或许不能真的帮你远离流感—
but if nothing else, if you were sick, it probably stopped you from infecting everyone else.
但是，如果你患上流感的话，面罩或许能够防止你传染给其他人。
At first glance, those masks might seem really effective -- even according to some research.
初看上去，这些面具似乎真的有效—甚至一些研究也是这么表明的。
In one 2009 study, almost 450 nurses in Ontario, Canada, were assigned to wear either a simple surgical mask or an N95 respirator.
2009年的一项研究中，指派加拿大安大略省将近450名护士要么带上简单的医用口罩要么带上N95呼吸器。
These are specially designed masks that mold closely to the face and block at least 95% of tiny particles.
——特别设计的口罩，紧贴面部并能阻挡至少95%的微粒。
That study, published in JAMA, found that about 23% of nurses ended up catching the flu regardless of the form of protection they used.
发表于《JAMA》的那项研究发现约23%的护士最终染上了流感，不论他们使用的是何种防护形式。
So case closed, right? Masks must work at least as well as those fancy respirators at keeping people flu-free.
所以，可以结案了。口罩以及那些昂贵的呼吸器至少能够保护人们免受流感困扰。
Except… that's probably not the case. See, there's a difference between getting sick and being exposed to flu virus.
除了...其实并非如此。感染流感和被暴露于流感病毒之中还是有区别的。
And other studies have shown that surgical masks are definitely worse at keeping out viruses.
其他研究表明医用口罩抵御病毒的效用绝对是最差的。
One of those studies, published in American Journal of Infection Control in 2006,
2006年，出版于《美国感染病控制期刊》的研究之一
used samples of a harmless virus to test how good respirators and surgical masks are at protecting their wearers from airborne pathogens.
利用一种无害病毒的样本测试呼吸器和医用口罩能够如何有效保护佩戴者远离空气传播的病原体。
They found that 20 to 85% of the simulated pathogens penetrated the surgical masks, compared to only around 5% for the respirators.
他们发现20%到85%的模拟病原体渗透进了医用口罩，而渗透呼吸器的仅5%左右。
Which is quite the difference.
这个区别相当大了。
So even if both groups of nurses in that first study got sick just as often, the ones wearing surgical masks were probably exposed to a lot more particles.
所以即使第一组实验中的两组护士染病，那些戴着医用口罩的护士或许暴露于更多的微粒之中。
If you think about it, though, that really isn't that surprising.
如果你仔细想想，这并不惊奇。
Because here's the thing: Surgical masks aren't actually designed to protect you from dangerous particles in the environment.
因为实际上，医用口罩的设计并非真的用于保护你远离环境中的危险微粒的。
Only respirators are. Instead, the masks intended for the opposite job -- protecting other people from your germs.
只有呼吸器是的。相反，医用口罩的目的在于保护其他人远离你的病毒。
See, while respirators fit tightly to your face, surgical masks often have gaps on the sides.
明白了不，呼吸器紧密贴合你的面部，而医用口罩常常在两颊边留有空隙。
They still do a good job covering your mouth and nose, but outside particles can probably sneak in around the mask.
它们还是能很好的遮住你的嘴和鼻子，但是外在微粒能够从口罩周围溜进去。
So even if they do happen to keep you healthy, that's not their main purpose.
所以即使它们确实碰巧保护了你，这也不是它们的主要目的。
Still, when it comes to containing your germs, they're definitely effective.
但是在牵制你的病毒方面，它们绝对有效。
For a 2013 study published in the journal PLOS Pathogens, scientists collected examples of exhaled particles from about 40 flu patients with and without surgical masks.
发表于《PLOS Pathogens》期刊中的一项2013年的研究，科学家从约40名戴或不戴医用口罩的流感患者中收集呼吸微粒的样本。
They found that the masks significantly reduced the amount of aerosolized virus that their subjects put into the air.
他们发现口罩能够显著减少主体传入空气中的物化病毒的数量。
And a 2009 study from the journal Clinical Infectious Diseases found that surgical masks were just as effective as fancy respirators at keeping the illness from spreading.
发表于《临床传染病》期刊的一项2009年的研究发现医用口罩在阻止疾病传播方面和呼吸器一样有效。
This is why doctor's offices will ask patients who are coughing or sneezing to put on a mask while they're in the waiting room -- to protect everyone else.
这就是诊疗室要求候诊室内咳嗽或打喷嚏的病人戴上口罩的原因—为了保护其他人。
According to a Mayo Clinic expert, if you're not sick yourself, just worried about catching the flu, wearing a paper mask might help, and it certainly won't hurt.
梅约诊所一名专家称，如果你没有生病，而只是担心染上流感的话，可以带一个口罩，绝对不会带来伤害。
But your best bet is still to suck it up and go get that flu shot.
但最好的办法还是忍住并去注射流感疫苗。
Thanks for watching this episode of SciShow!
感谢收看本期《科学秀》！
And special thanks to Lorraine on Patreon for asking, and to all our patrons who voted to have this question answered!
特别感谢Patreon赞助人Lorraine的提问，也感谢所有为这个问题投票的赞助人！
If you'd like to submit a question or vote on the next ones we answer, you can go to patreon.com/scishow.
如果你想提问或是为下一期节目投票，请登录patreon.com/scishow
