沙巴体育手机登录 that it limits the spread of respiratory viral infections in hospitals. But there is no that surgical masks protect members of the public from getting or passing on these sorts of infections—most likely because of incorrect use. For cloth masks worn by the public, the .
surgical masks are made up of several layers of nonwoven plastic and can effectively filter very small particles, such as droplets of sars-cov-2 (the virus that causes covid-19). the masks typically contain an external waterproof layer and an internal absorbent layer.
although masks made from scarves, t-shirts, or other fabrics can’t provide the same level of protection and durability as surgical masks, they can of the large droplets exhaled by the wearer, hence protecting others from viral exposure. but their ability to filter droplets depends on their . multilayered cloth masks are better at filtering but harder to breathe through. and they become wetter quicker than single-layer masks.
沙巴体育手机登录the question we need to ask is not so much whether cloth masks offer as good a protection as surgical masks ( they don’t, and perhaps that’s fine), but whether there are serious unintended consequences of recommending their widespread use by members of the public.
when deciding if a safety measure is worth introducing at scale, it’s important to balance any benefits against potential harms. here are four potential consequences that, unless mitigated against, could make things worse. forewarned is forearmed.
The big four
沙巴体育手机登录first, what’s become known as the suggests that introducing one safety measure, such as car seatbelts, may lead to other, compensatory risk behaviors, such as speeding. (if you perceive that your car is safer than usual, you might compensate for this by driving faster.) in the context of covid-19, it has been argued that the wearing of a mask may make people feel safer, and hence protective behaviors that we know to be effective, such as social distancing and regular hand washing.
although we don’t have clear evidence that this is happening during the pandemic, a few studies conducted before the outbreak found that people did indeed have when wearing a mask.
沙巴体育手机登录second, to offer any protection, masks need to be worn correctly and consistently when in contact with other people. most studies conducted so far—none of which were conducted during the current pandemic—didn’t explicitly look at the level of adherence to mask wearing. those that did , ranging from “good” to “poor.”
沙巴体育手机登录it’s important to note, though, that the a disease seems and the more susceptible people feel, the more likely they are to protect themselves during a pandemic. given the high number of global infections and deaths, people may display greater than typical levels of adherence to mask wearing during the pandemic.
third, masks may act as an extra transmission route or prompt other behavior that transmits the virus, such as . to stop masks being turned into alternative transmission routes, they need to be safely put on and taken off.
沙巴体育手机登录people touch their faces on average—an itchy or poorly fitted mask may mean that people touch their even more regularly. after touching your mask, there’s a risk that your hands become contaminated, with the risk that you will then spread the virus , such as door handles, railings, or tables.
fourth, researchers have calculated that if the entire u.k. population started using disposable masks daily, it would create a significant environmental hazard, namely (46,000 u.s. tons) of potentially contaminated and unrecyclable plastic waste per year. (a figure was not estimated for the united states.)
沙巴体育手机登录also, most people will have noticed the increased littering of masks in community spaces, which may act as environmental and infection hazards. reusable rather than disposable masks are therefore preferable.
and public health bodies now recommend that members of the public use masks in places where it’s difficult to maintain social distancing, such as on public transportation. we strongly urge readers to carry on with good hand hygiene and social distancing, not touching their face and using reusable (rather than disposable) face coverings—and safely disposing of them at the end of their useful life.
is a research associate in behavioral science and health at , and is a PhD candidate in zoonotic infections at the . This article is republished from under a Creative Commons license. Read the .