“双重口罩”预防新冠肺炎?专家认为这是个好主意

“双重口罩”预防新冠肺炎?专家认为这是个好主意

As COVID-19 cases continue to surge around the world and new highly infectious variants are on the loose, some people have started doubling up on masks by wearing two on top of each other. This might sound unnecessary or overly cautious, but many leading health experts are arguing it could help to further stop the spread of COVID-19.

随着新冠肺炎病例在全球持续激增，新的高传染性变异病毒仍在蔓延，一些人开始加倍戴口罩，一次戴两个。这听起来可能没有必要或过于谨慎，但许多知名卫生专家认为，这可能有助于进一步阻止COVID-19的传播。

The idea behind this is simple: COVID-19 is caused by an airborne virus and can spread by aerosolized droplets of salvia that have become laced with the virus. If you wear a covering across your nose and mouth, many of these droplets will be filtered and blocked from flowing into the surrounding air, reducing the risk of transmission of the virus. However, since these infectious droplets are so small, a mask can not stop 100 percent of the viruses seeping through into the surrounding air.

这背后的想法很简单:COVID-19是由空气传播的病毒引起的，可以通过含有病毒的鼠尾草雾化飞沫传播。如果你在鼻子和嘴巴上戴上覆盖物，很多飞沫就会被过滤并阻止流入周围的空气，从而降低病毒传播的风险。然而，由于这些传染性飞沫如此之小，口罩不能100%阻止病毒渗入周围空气。

One solution to this problem is wearing an N95 mask, which is designed to achieve a very close facial fit and is around 95 percent effective at blocking tiny particles 0.1 to 0.3 microns in size. Alternatively, simply wearing two masks could help to add another layer of protection.

解决这个问题的一种方法是佩戴N95口罩，这种口罩的设计目的是让面部非常贴合，在阻挡0.1到0.3微米大小的微粒方面，其有效性约为95%。另外，简单地戴两个口罩可以帮助增加一层保护。

Tom Hale

“A mask is like an obstacle course for particles to get through,” Linsey Marr, an expert in airborne virus transmission and a professor of engineering at Virginia Tech said speaking to the AARP focus group. “Adding a second mask adds another obstacle course, increasing the chance that the particle will be trapped before it gets through to the other side."

病毒通过空气传播的专家、弗吉尼亚理工大学的工程学教授林西·马尔在接受美国退休人员协会(AARP)小组采访时说:“口罩就像是粒子穿过的一道障碍。增加第二个面罩增加了另一个障碍，增加了粒子在穿过另一边之前被困住的机会。”

Marr published a study late last year looking at this question and found that simply wearing at least two layers of either a high-quality surgical mask or a tightly fitted fabric mask could block up to 90 percent of infectious particles – nearly as effective as an N95 mask.

Marr在去年年底发表了一项研究，研究了这个问题，发现只要戴上至少两层高质量的外科口罩或紧密贴合的织物口罩，就能阻挡高达90%的传染性颗粒——几乎和N95口罩一样有效。

Dr Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases, is also a backer of this idea. When TODAY asked him whether a “double mask” provides more protection, he replied: “You know, it likely does, because this is a physical covering to prevent droplets and virus to get in.”

美国国家过敏和传染病研究所所长安东尼·福奇博士也是这一观点的支持者。当被问及“双层口罩”是否能提供更多保护时，他回答说:“可能可以，因为这是一种物理覆盖物，可以防止飞沫和病毒进入。”

“So, if you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective, and that’s the reason why you see people either double-masking or doing a version of an N95,” Dr Fauci added.

福奇博士补充说:“所以，如果你用一层物理覆盖物盖上一层，再盖上另一层，这是很正常的，它可能会更有效。这就是为什么你看到人们要么用双层遮盖物，要么用一种版本的N95。”

Whatever mask you wear, it's important to ensure it fits snuggly on the face and completely covers your nose and mouth. Not all face masks are created equal, however. A study published in the journal BMJ Open last year found that N95 masks were highly effective at filtering out ultrafine particles expelled at the velocity of a human cough, but vacuum bags were found to be even more effective, while other available materials were also comparable, with a few caveats. Lightweight t-shirt material was found to be the least effective face mask material, although it still blocked some particles.

无论你戴什么口罩，重要的是要确保它紧贴着你的脸，并完全罩住你的鼻子和嘴。然而，并不是所有的口罩都是一样的。去年在BMJ杂志上公开发表的一项研究发现,N95口罩在过滤以人类咳嗽速度排出的超细颗粒方面非常有效，但真空袋被发现更有效，而其他可用材料也可以进行比较，但有几点需要注意。轻质t恤材料被发现是效果最差的口罩材料，尽管它仍然可以阻挡一些颗粒。