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口罩降低 85%的感染 以色列人还是放弃口罩

已有 288 次阅读2024-1-13 15:56 |个人分类:medicine

尽管大量研究表明戴口罩可以降低 85% 的感染风险,但以色列人还是放弃了戴口罩

https://www.timesofisrael.com/as-more-israelis-ditch-masks-massive-study-says-they-cut-infection-risk-by-85/

以色列专家支持荟萃分析的结论,促使世卫组织改变立场,称面罩“确实可以拯救生命”,是一项良好的长期公共战略

作者:NATHAN JEFFAY 2020 年 6 月 9 日,

正如越来越多的以色列人丢弃口罩一样,其有效性的证据也越来越多,世界卫生组织正在改变其建议以鼓励使用口罩。
世界上最大规模的关于用面罩防御新型冠状病毒的研究结果已经出炉,结果表明风险显着降低。

加拿大领导的一个团队今年早些时候在同行评审医学杂志《柳叶刀》上发表了对全球口罩研究的荟萃分析,该团队表示,在遇到感染者时,佩戴面罩可将感染 COVID-19 的几率降低 85% 月。

以色列正经历冠状病毒病例激增,政府周一晚间表示,过去 24 小时内新增确诊病例 179 例。 总理本杰明·内塔尼亚胡已为进一步放宽病毒限制“紧急刹车”。

周日,内塔尼亚胡指责该国减少了对预防措施的遵守,包括戴口罩。 他在内阁讲话时表示,最近病例激增的部分原因是国家开放,“但其中一部分显然也源于对口罩、距离和卫生规则的严格遵守的放松。” 以色列已有近 300 人死于该病毒,目前有近 3,000 例活跃感染病例。

世界卫生组织资助的研究小组在《柳叶刀》上发表了研究结果,发现感染者周围的健康人通过戴口罩,感染冠状病毒的几率从 17.4% 降低到 3.1%。 保持一米(3 英尺)或更远的距离可将感染率从 12.8% 降低至 2.6%,并且当距离增加到两米或三米时,社交距离变得更加有效。

尽管世界各地的卫生当局在大流行期间迅速呼吁保持社交距离,但许多人对于要求人们戴口罩却更加犹豫。 世界卫生组织最初表示,没有证据支持要求健康人戴口罩。 但在过去几天里,自从这项新研究发布以来,它改变了立场,现在鼓励在许多公共场所使用口罩。 世界卫生组织目前认为,口罩可以成为“潜在传染性飞沫的屏障”。
“口罩确实可以拯救生命”
在以色列,4月1日起,公众被要求在公共场合戴口罩,这一时间早于许多其他国家,随后口罩的使用也被写入法律,但官员们表示,现在许多人没有遵守这一指示。 一些专家表示,这项新研究可能正是他们说服人们戴口罩并遵守社交距离的艰苦斗争所需要的。

免疫学家西里尔·科恩告诉《以色列时报》:“这是一个客观的科学证明,口罩确实可以拯救生命。” “这很重要,因为它用统计数据支持了我们认为并相信是正确的。”

Cyrille Cohen,巴伊兰大学免疫治疗实验室负责人。 

巴伊兰大学免疫治疗实验室负责人科恩补充道:“结论是,戴口罩可以限制感染和污染,当我们处于禁闭期后、人们外出时,这一点非常重要。” 当你在以色列的街道上看到人们常常不戴口罩时。”

免疫系统专家托默·赫兹表示,这项新研究有助于挑战人们对口罩的普遍看法。 “这表明口罩有助于保护佩戴者,而不仅仅是保护他人,”他说。

赫兹是内盖夫本古里安大学微生物学、免疫学和遗传学系的教员,他补充道:“研究表明,戴口罩对公众来说是一项很好的长期策略。”

《柳叶刀》研究发表之际,另一家期刊撤回了一篇对口罩有用性提出质疑的论文。

一个月前,《内科医学年鉴》发表了一篇文章,声称感染者佩戴口罩并不能阻止他们在咳嗽时传播 COVID-19。 韩国蔚山大学的一个研究小组写道,口罩“似乎无法有效防止患者咳嗽中传播 SARS-CoV-2”。 上周二,研究人员写道,编辑要求他们撤回文章,并承认他们的结果“无法解释”。

由加拿大麦克马斯特大学的 Derek Chu 领导的《柳叶刀》研究是对在 16 个国家和六大洲进行的约 172 项研究的荟萃分析,这些研究跟踪了遵循推荐做法的人们的健康状况。 他们重点关注 COVID-19 以及由同一病毒家族引起的其他感染:严重急性呼吸综合征 (SARS) 和中东呼吸综合征 (MERS)。

大约三分之一的研究跟踪了那些没有采取预防措施的人和那些采取了预防措施的人,以便进行比较。 作者认为,他们的论文是第一篇“快速综合有关 COVID-19 的所有直接信息”的论文,因此为抗击病毒的干预措施“提供了最佳的现有证据”。

他们强调了通过眼睛感染的危险,这表明眼睛保护措施没有得到充分利用。 他们写道,当人们触摸眼睛时以及当 COVID-19 阳性者的飞沫通过空气到达另一个人的眼睛时,都可能发生感染。

他们写道:“眼睛保护通常被忽视,但在社区环境中可能是有效的。”他们报告说,健康人在遇到冠状病毒感染者时,通过增加眼睛保护,可以将感染机会从 16% 降低到 5.5%。
《柳叶刀》研究还研究了不同类型的口罩,得出的结论是,一次性口罩比现在流行的通常由单层制成的织物口罩更有效。 研究人员写道:“与单层口罩相比,N95 和外科口罩的防护作用更强。”

巴伊兰大学的科恩表示,在大流行期间,科学家们需要一段时间才能充分了解口罩等干预措施的力量。

“人们一开始说病毒很小,所以口罩不起作用,但我们知道它是通过飞沫传播的,而且当你谈论飞沫时,它们比单独的病毒还要大,而且物理屏障 很有效,”科恩说。

世界卫生组织的研究发现,戴口罩后感染风险明显降低 85%。

Israelis ditch masks, even as massive study says they cut infection risk by 85%

https://www.timesofisrael.com/as-more-israelis-ditch-masks-massive-study-says-they-cut-infection-risk-by-85/

Israeli experts back conclusions of meta-analysis that prompted WHO to change its position, say face coverings ‘do actually save lives’ and are a good long-term public strategy

By NATHAN JEFFAY 9 June 2020, 

Just as Israelis are discarding face masks in increasing numbers, evidence of their effectiveness is growing and the World Health Organization is changing its advice to encourage their use.

Results are in for the world’s biggest study on face coverings to defend against the novel coronavirus — and they point to a major reduction in risk.

Wearing face coverings cuts chances of COVID-19 infection by 85 percent upon encountering someone with the virus, according to a Canadian-led team that published a meta-analysis of worldwide mask research in The Lancet, a peer-reviewed medical journal, earlier this month.

Israel is experiencing a spike in coronavirus cases, and the government on Monday evening said there were 179 new infections confirmed over the preceding 24 hours. Prime Minister Benjamin Netanyahu has pulled “the emergency brake” on further easing the virus restrictions.

On Sunday, Netanyahu rebuked the nation for reduced adherence to precautions, including face coverings. Addressing the cabinet, he said that part of the recent spike in cases is a result of opening up the country “but some of it also clearly stems from a loosening in strict adherence to the rules regarding masks, distancing and hygiene.” Israel has seen nearly 300 deaths from the virus, and currently has nearly 3,000 active infections.

The World Health Organization-funded team that published its findings in The Lancet found that healthy people who are around an infected person reduce their chances of catching coronavirus from 17.4% to 3.1%, by wearing a mask. Staying a meter (3 feet) or more apart reduces infection rates from 12.8% to 2.6% — and social distancing becomes even more effective as the distance increases to two or three meters.

While health authorities around the world were quick to call for social distancing during the pandemic, many have been more hesitant about asking people to wear masks. The WHO initially said there was no evidence to support asking healthy people to wear masks. But over the last few days, since the new study was released, it has changed its position, and now encourages the use of masks in many public settings. The WHO currently takes the view that masks can be “a barrier for potentially infectious droplets.”

‘Masks do actually save lives’

In Israel, the public was told to wear masks in public on April 1, earlier than in many other countries, and their use was then enshrined in law, but officials say that many people are now failing to follow the instruction. Some experts say the new study could be just what they need in their uphill struggle to convince people to wear masks and observe social distancing.

“It’s an objective scientific demonstration that masks do actually save lives,” immunologist Cyrille Cohen told The Times of Israel. “It’s important because it backs up with statistics what we thought and believed to be correct.”

Cyrille Cohen, head of the immunotherapy laboratory at Bar-Ilan University. (Courtesy)

Cohen, head of the immunotherapy laboratory at Bar-Ilan University, added: “The conclusion is that wearing masks can limit infection and contamination, and this is very important when we’re in a period after confinement, when people are going out, and when you see in streets of Israel people often aren’t wearing masks.”

Immune system expert Tomer Hertz said the new study helps challenge a common perception about masks. “This shows that masks are good for protecting the person wearing them, and not just for protecting others,” he said.

Hertz, a member of faculty at Ben-Gurion University of the Negev’s Microbiology, Immunology and Genetics, added: “The study shows that masks are a good long-term strategy for the public.”

The Lancet study comes as another journal retracted a paper that had cast doubt on the usefulness of masks.

A month ago, Annals of Internal Medicine published an article claiming that masks worn by infected people don’t stop them transmitting COVID-19 when they cough. Masks “seem to be ineffective in preventing the dissemination of SARS–CoV-2 from the coughs of patients,” wrote a team from University of Ulsan, South Korea. Last Tuesday the researchers wrote that editors had asked them to retract their article, and admitted that their results were “uninterpretable.”

The Lancet research, led by Derek Chu of Canada’s McMaster University, was a meta-analysis of some 172 studies that have been conducted in 16 countries and six continents tracking the health of people who followed recommended practices. They focused on COVID-19, and other infections caused by the same family of viruses: severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).

Around a third of the studies tracked people who didn’t take precautions as well as those who did, for the sake of comparison. The authors believe theirs is the first paper to “rapidly synthesize all direct information on COVID-19” and therefore “provide the best available evidence” on interventions to fight the virus.

They highlighted the danger of infection via eyes, suggesting that eye protection isn’t used enough. They wrote that infection can occur both when people touch their eyes and when droplets from a COVID-19-positive person reach the eyes of another through the air.

“Eye protection is typically under-considered and can be effective in community settings,” they wrote, reporting that healthy people encountering a person ill with the coronavirus can cut the chance of infection from 16% to 5.5% by adding eye protection.

The Lancet study also looked at different kinds of masks, and concluded that disposables masks are more effective than the now-fashionable fabric masks, normally made from a single layer. “Both N95 and surgical masks have a stronger association with protection compared with single-layer masks,” wrote the researchers.

Cohen, of Bar-Ilan University, said it took time during the pandemic for scientists to fully understand the power of interventions like masks.

“People said at first that the virus is so tiny so the masks won’t be effective, but we understand that it’s passed through droplets, and that the moment you’re talking about droplets they are larger than the virus alone, and physical barriers are effective,” said Cohen.

WHO study found an apparent 85% reduction in infection risk when masked.

The World Is Masking Up, Some Are Opting Out

https://www.bloomberg.com/graphics/2020-opinion-coronavirus-global-face-mask-adoption/

By Elaine He and Lionel Laurent 

Nothing symbolizes our battle with the novel coronavirus like the face mask — it’s the most visible, humbling and contentious reminder of the deadly, invisible invader that we must live with until we find a vaccine.

In 2020, wearing a mask in cities like New York, London or Paris has gone from being a marker of the paranoid or vulnerable to the badge of the conscientious in the era of Covid-19. Even U.S. President Donald Trump put one on after previously disparaging them. Several studies suggest face coverings help — provided they’re properly made, maintained and worn — in limiting the spread of tiny exhaled particles carrying the coronavirus.

Still, not everyone’s wearing them.

The initial guidance from health officials was confusing, with many saying masks were only necessary for medical professionals or people exhibiting symptoms of infection. Or that only certain types of masks were effective. A shortage of supplies didn’t help either.

survey early on in the pandemic by Germany’s Max Planck Institute for Demographic Research found that mask-wearing in the West lagged far behind other precautions, such as keeping one’s distance from other people, regularly washing one’s hands and avoiding public transport.But as the health advice evolved to emphasize wearing masks, so did some personal practices. Pollster YouGov has been surveying people’s self-reported mask-wearing habits globally and three distinct patterns emerge from the findings.

Areas where most residents were used to wearing masks or were willing to adopt them quickly to protect against Covid-19

Then there are countries that had fewer people wearing masks to start with, but quickly took up their use

Finally, another group is still bucking the trend, with a minority of residents wearing masks. Some of these countries quickly contained their outbreaks, but others had extremely high death tolls

All of the areas that had high mask usage to start with, and where the practice of wearing face masks remained elevated in response to the pandemic, are in Asia.

That’s where the Covid-19 outbreak began and where the 2003 SARS outbreak is ingrained in people’s memories. Some places mandated face masks along the way. Japan gave cloth masks out to the public without imposing a draconian lockdown. That alone may have saved lives.

Places that had low mask usage initially, but where adoption subsequently rose, had different experiences of the outbreak. Yet there’s a unifying theme: Usage significantly rose after rules were established around wearing them.

High reported usage in France, where people needed a self-signed permission form to leave home at the height of lockdown, and Spain, where children weren’t allowed outside, reflects high death tolls, strict lockdowns and mandatory mask policies in those countries.

In the U.S., state politicians and the private sector are taking matters into their own hands: All but two states have at least some mask requirements, according to volunteer organization Masks4All, including New York, which accounts for almost a quarter of the country’s virus death toll. That’s a big reason why more than 70% of Americans report having worn a mask, according to YouGov. Meanwhile, restaurant and retail chains like Walmart Inc., McDonald’s Corp. and Starbucks Corp. are requiring them in their establishments.

Experiences in countries where the virus has remained relatively under control underline the power of clear policies over gentle nudging or relying on people’s common sense.

Germany, lauded for its cautious, consistent handling of the outbreak, saw adoption surge after introducing mask-wearing rules in April. There was a significant jump in Mexico after local governments mandated their use and gave out masks free. Singapore’s level shot up to 90%, from around 23% in early March, after the government ceased discouraging residents from donning face coverings, distributed them free and made them compulsory with a fine for failing to comply.

Then there are the countries where mask usage has stayed low.

In some places, such as Denmark, Finland and Norway, that’s easy to understand. Their Covid-19 outbreaks have been relatively contained, with among the lowest death tolls in the world. So low mask adoption doesn’t necessarily signal a policy failure. After all, masks are only one tool among many, and they’re by no means a panacea where they are in use.

Denmark’s health authority has discouraged mask wearing for healthy people going about their normal lives, questioning its effectiveness and saying it “can cause more harm than good.” There have been concerns that people who cover their mouth and nose may let down their guard or that face coverings may even become a vector for the virus if mishandled.

One Italian study, however, shows masks did encourage people to keep their distance. The U.S. CDC recommends wearing cloth masks as a preventative measure, while a WHO study found an apparent 85% reduction in infection risk when masked.

What’s striking about the low-mask-wearing group is that it includes Nordic neighbor Sweden, where a decision to keep much of society open as the outbreak worsened has led to a considerably higher mortality rate. Even as calls multiply for government measures such as rules on masks, Swedes aren’t taking it upon themselves to wear them.

The U.K. is even more confounding. It has the highest death toll in Europe, yet only 38% of respondents to YouGov’s latest tracker poll said they wore a mask. They cite many reasons, including staying home, inconsistent guidance and a failure of leaders to be role models. Prime Minister Boris Johnson was only recently pictured wearing a mask for the first time, in spite of overcoming a serious bout with Covid-19 in April.

When clear rules are introduced, such as last month’s public transport requirements in England and Scotland, Brits show they will comply. In fact, an Ipsos MORI survey in April and more recent results from YouGov in July found that though few Brits wear face coverings, a large majority support doing so or would wear them if the government mandated it. As part of efforts to jumpstart the economy, England will follow Scotland in requiring masks be worn in shops starting July 24.

Even rules can become politicized, though, as seen in the U.S. and Latin America, where the stakes are arguably the highest. Strongmen leaders who revel in tough-guy personas don’t generally like face masks: Brazil’s Jair Bolsonaro has watered down his own country’s mask law, while Trump’s resistance to wearing a mask (until his recent change of heart) has given succour to American anti-maskers who skew Republican.

All in all, masks are gaining momentum as countries reopen their economies while battling a virus that’s still very much with us. The looming challenge will be overcoming resistance from people who remain unconvinced by their merits or fatigue from those who feel Covid-19 is less of a threat.

As with changing social behavior on safety issues, such as wearing a seatbelt or not driving when drunk, mask adoption will take time and effort. The limits of enforcement will likely lead to more carrot-and-stick approaches: Masks should ideally be free or widely distributed, government messaging should be clearer on where masks are required and why, and fines should be levied where necessary. Masks themselves should become more comfortable and fashionable to wear.

Until we have a vaccine or effective treatment, all countries should be on their guard. Once the mask straps start to loosen, they may do so for good.

Development by Jeremy Scott Diamond

Note: YouGov surveys have a margin of error +/–3 percentage points and their sample size is 1,000 to 2,000 people in each country. Figures cited in the story are from their tracker survey which asks about wearing a mask in public in the past two weeks specifically to protect against coronavirus. The YouGov/Imperial College survey asks about frequency of mask usage in the past seven days.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

To contact the authors of this story: Elaine He at ehe36@bloomberg.net and Lionel Laurent at llaurent2@bloomberg.net
To contact the editor responsible for this story: Melissa Pozsgay at mpozsgay@bloomberg.net


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