America's top doctor has some clear guidance about beating coronavirus: forget face masks. https://trib.al/AL1NdMk
The U.S. Surgeon General urged people to “stop buying masks,” saying on Twitter that they’re not effective in preventing the general public from catching coronavirus.
“The best way to protect yourself and your community is with everyday preventive actions, like staying home when you are sick and washing hands with soap and water, to help slow the spread of respiratory illness,” Jerome M. Adams said in a tweet.
He encouraged people to get flu shots, saying fewer flu patients means more resources for fighting the virus.
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ENVIRONMENT & HEALTH HONG KONG
Coronavirus: A definitive guide to buying and using face masks, by a viral immunologist
2 March 2020 13:10
Guest Contributor
12 min read
By Dr. Ariane M. Davison
Hong Kong is being re-traumatised in 2020 – by another crisis that, like SARS in 2003, is devastating society and financial markets. Similarly, a lack of knowledge and information on the coronavirus outbreak that originated in Wuhan, China have caused wild panic and chaos as well as a global scramble for face masks, from Hong Kong to London and New York. The topic of face masks, the many types available, how they are put on, the ways they are worn incorrectly and dangerously, the stockpiling of masks for inflated secondary sales, the “recycling” of masks for personal use or resale and the conversion of household items like pomelo rinds, feminine hygiene products and plastic water bottles into makeshift face shields are just some of the issues we’ve been re-visiting with the arrival of the new coronavirus, which the World Health Organization recently renamed Covid-19.
Photo: GovHk.
In stores and online (if not sold out already) there are face masks of every grade, material, style and variety: masks made from medical-grade paper, decorative paper masks in a rainbow of colors, sleek polyurethane Pitta masks, washable fabric masks and reusable dust and allergy masks. Most of these products provide absolutely no protection against the novel coronavirus or other viruses.
Which masks can offer protection? Surgical face masks and N95 respirators, which filter viruses from the air with up to 95% efficiency; even though viruses are smaller than the filter spaces, they become trapped in the mask layers and by ionically binding to the filter material. But even the best face masks are often worn and disposed of incorrectly, and many of the masks on the market are also counterfeits.
The market in Hong Kong is relatively unregulated, and the advertised claims of many face masks for sale, especially online, are inflated or outright false, yet the allure of protection against terrifying diseases like the coronavirus plays on human fear and opens up wallets. As a result, many people end up buying the wrong mask or wear a good mask incorrectly, with compounded misuse potentially helping spread rather than prevent dangerous respiratory pathogens like Covid-19. Lulled into a false sense of security, a mask-wearing user might enter high-risk areas, expose themselves to more coronavirus dangers and continue on to exponentially infect others.
Common face mask use mistakes
Let’s take a look at some common issues regarding face mask use:
A mask is worn upside down, only over the nose, not pulled under the chin, or worn only over the mouth, leaving the nose exposed. Even the best mask won’t protect if worn incorrectly.
Photo: Tom Grundy/HKFP.
A user constantly touching and fiddling with the mask’s filter surface, which cross-contaminates fingers and subsequent surfaces. A contaminated finger will cross-contaminate the next SEVEN surfaces it touches, e.g. phones, ipads, keypads.
Pulling a face mask under the chin for conversation or eating, and then putting the mask back up again.
Reusing or recycling masks. This has been a common and dangerous emerging practice in Hong Kong since January 2020.
Wearing the same mask for too long. The length of time that a face mask could be safely worn depends on the number of people a user has been around. The outer layer of a mask is the ultimate barrier. Like a fishing net, it will filter but also accumulate pathogens, without inactivating or killing them. The longer a mask has been worn around others, the more concentrated the infectious load becomes. A face mask should never be worn longer than a day; a doctor or nurse will go through multiple masks during a single work shift.
Used masks are not disposed of quickly and appropriately. Used masks have a build-up of potentially infectious particulates that could include coronavirus and other pathogens, and if left around, they can cross-contaminate previously clean areas.
Using a counterfeit face mask. The gold standard for surgical face masks is ASTM-F2100. But there are many masks that look similar, made of cheap materials that do not meet that standard and do not provide an adequate barrier against disease. Only buy from reputable sellers; face masks made from substandard material abound online.
Relying on N95 masks. When worn properly, these respirator masks get very hot inside and are very difficult to breathe in due to the pressure change between the air inside and the outside atmosphere. It is like breathing through a blanket and can become distressing to the user. A user’s blood-oxygen saturation can drop and carbon dioxide increases significantly with correct and prolonged use. Even a healthy and fit adult could find wearing an N95, if put on correctly, difficult after an hour or so of use. An older person or an immunocompromised individual likely would have a very hard time using an N95 mask even for a short time. Wearers may take it off for a break which would reduce its protection. Children and infants are also generally not appropriate candidates for wearing N95s as the risk of suffocation is higher.
Face masks to avoid
Let’s now look at other masks that people have been wearing during these desperate and confusing times to avoid Covid-19:
An inferior mask made of fabric, paper or plastic, or a dust or allergy mask is chosen and worn into a high-risk area.
Photo: Stand News.
A Pitta mask with an “N95 insert.” Pitta masks are made of porous sponge material, with no filter throughout the mask except for the small circle valve insert.
Homemade masks and face shields crafted from fruit, raincoats, women’s underwear, cardboard boxes, plastic bottles and other household items. These offer no protection against the coronavirus and confer only a false sense of safety for the desperate.
Recently, the South China Morning Post, citing research by the University of Hong Kong, published a do-it-yourself guide for making face masks at home using paper towels and tape. The article claims these home-made masks can confer 80-90% of the protection of manufactured face masks. In fact, this is an extremely unsafe practice, and irresponsible public guidance.
In addition to the barrage of filtration, bacterial, droplet, pressure, splash and flammability testing that a proper surgical face mask must undergo to secure its U.S. Food and Drug Administration (FDA), American Society of Testing Materials (ASTM) or International Organization for Standardization (ISO) classification and approval, it must be emphasized that NO COMPONENT of a medical-grade surgical mask is made of paper. Surgical masks are composed of three to four layers — including spun-bond or meltblown polypropylene (the filter layer), a high-density non-woven layer of polypropylene cellulose/polyester, and layer(s) of melt-blown polypropylene filter material toward the face side.
If you don’t have an authentic face mask, it’s best to keep a safe distance from others, socially isolate yourself and practice good hand hygiene until we have a better understanding of Covid-19.
According to the World Health Organization, wearing medical masks when not appropriate not only causes unnecessary costs but can cause users to feel a false sense of security. Habits such as diligent hand-washing and not touching your face likely provide better protection against the coronavirus. However, Hong Kong has one of the world’s highest population densities per square kilometer. It is almost impossible to avoid crowded places, to stand at least 2 to 3 meters from anyone, let alone manage to avoid a close-contact cough or a sneeze. The best option is to stay home. Not much fun, is it?
How to choose a good mask
Against these warnings, if you are still adamant about wearing a face mask, what type should you choose? Debates — both social and academic — rage online about the usefulness of surgical face masks during outbreaks of respiratory pathogens like the coronavirus. However, proper surgical or N95 mask use in conjunction with diligent hand-washing have been shown to reduce the spread of respiratory illness.
File Photo: Kaiser/United Social Press.
Although surgical face masks and respirators have been studied for decades, in hospitals, under surgical conditions and in pandemics, questions abound regarding their actual usefulness. A systematic review of the research literature, such as the Journal of the American Medical Association, shows that properly worn surgical face masks and N95 respirators are equivalent to each other. However, given the real-life user difficulties with N95 respirator masks, the most practical for consumer use would be an ASTM-F2100 surgical facemask.
Quality masks that offer trusted protection are approved and verified by international regulatory bodies (such as ASTM, FDA or NIOSH) and will have respective certification codes on the packaging. To guard against fake masks, buyers would be well-advised to search for reputable sellers offering trusted brands such as Kimberly Clark or 3M.
More recently, companies have begun offering surgical and N95 masks with novel antiviral and antimicrobial inclusions embedded into the normal filter layers. Such a face mask was developed by a small Hong Kong company called Filligent Limited, and in 2012 it was awarded a U.S. FDA “First of Kind, First in Class” approval. (Full disclosure: I was the Research and Development Director responsible for Filligent’s FDA approval for this mask, but I have no current or ongoing financial interest in, or employment relationship with, the companies that now own the right to produce and sell it.)
Hongkongers queue for face masks. File photo: Tom Grundy/HKFP.
This antiviral surgical face mask was equivalent in all ways to a normal ASTM-F2100 surgical face mask used by hospitals and medical practitioners. Because the outer layer is hydrophilic, it absorbs sneezes and coughed droplets, and the compounds in the outer layer could inactivate a variety of respiratory viruses. The mask was tested against 15-plus strains of influenza type A and type B as well as swine, equine and avian influenza, all with 99.99% inactivation. They also worked to inactivate other respiratory and other common bacterial pathogens.
These masks, called the BioMask, can be worn for longer periods compared with standard surgical face masks. The issue of cross-contamination that can happen with surgical face masks is eliminated due to the antiviral compounds in the outer layer. The masks, which have been co-branded with CURAD and Medline, as well as Target’s “Up & Up” house brand, are available at CVS, Walgreens and Target in North America. However, supply for these antiviral masks as well as regular surgical face masks has been scarce since December 2019.
The right way to wear a surgical face mask
The first step is examining the mask. If it is damaged, throw it away.
If the mask looks okay, pull the loop around the ears, expand the mask over the nose and chin and make sure it has a snug fit. Do not touch the surface of the mask when putting it on, while wearing it, or when taking it off.
Replace the mask if it is soiled with bodily fluids, either on the inside (by the wearer) or outside (through public exposure). But in general, surgical masks are single use items and should never be recycled or reused. Remove the mask only by touching the ear loops to avoid cross-contaminating fingers. Wrap and dispose of mask properly, and wash your hands.
What are we learning from all this?
The shortage of face masks in Hong Kong is a disgrace. In the aftermath of the SARS crisis in 2003, the Hong Kong government should have appropriated funds for contagion situations like the coronavirus and stockpiled sufficient face masks and other professional PPE (personal protection equipment) to protect public health workers and others at the coalface, such as medical practitioners, hospital employees, airport staff and sanitation workers.
Which leaves us asking: What more can you do to protect yourself and your loved ones from Covid-19, aside from becoming better educated on how to choose, wear and dispose of face masks properly? As the WHO points out, face masks alone are not enough to protect against the coronavirus.
Make sure to also wash your hands frequently with soap and water. This is superior to any kind of antimicrobial hand-gel as it completely banishes pathogens from your hands — your most active body part — simply by washing germs away. Use alcohol-based hand gel when soap and water are not available. Be sure to use a coin-sized amount of gel, and cover your hands and fingertips liberally.
Photo: GovHK.
Practice social distancing. In this era of social media, Skype and Zoom, there should only be special circumstances for in-person meetings at this critical time. Leave your shoes outside of your home. Frequently cleanse high traffic items that get touched a lot, such as door handles and elevator buttons, with diluted bleach or 70% alcohol gel. Avoid elevators and take the stairs!
Infectious disease experts agree that contagious outbreaks are going to become increasingly common as humans continue to encroach on natural ecosystems. Global populations are set to grow by another billion people in the next decade, so Ebola, SARS, MERS, Marburg and Covid-19 simply mark the emergence of a menagerie of new chimeric zoonotic viruses. It’s ignorant to assume that whatever disease is coming next won’t affect us similarly. They’re coming, it’s just a matter of when and how we can intelligently protect ourselves.
This article first appeared on Forkast.News. Dr. Ariane Davison is a Hong Kong-based viral immunologist and director of Global Health Care Consultants. She has comprehensive experience in the global healthcare, biotech, start-up, consulting and equities industries, with senior roles in Hong Kong, China and the U.S. in advisory and asset management. Among other achievements, in 2011 she led a research team that secured a “First in Class” U.S. Food and Drug Administration medical device approval for an ASTM antimicrobial and antiviral face mask. Davison earned her Ph.D. in medicine from the University of Sydney and has published in journals and textbooks.
冠狀病毒：病毒免疫學家購買和使用口罩的權威指南
阿里安·M·戴維森博士
到2020年，香港將再次遭受創傷，這是另一場危機，就像2003年的非典一樣，正在摧毀社會和金融市場。同樣，對源自中國武漢的冠狀病毒暴發的知識和信息的缺乏導致了從香港到倫敦 和 紐約的大範圍恐慌和混亂，以及全球對口罩的爭奪 。口罩的主題，可用的多種類型，佩戴方法，不正確和危險的佩戴方式，用於二次銷售膨脹的口罩的儲存，用於個人用途或轉售的口罩的“回收”以及對口罩的轉換柚皮，女性衛生用品和塑料水壺等家居用品 隨著新型冠狀病毒的到來，我們一直在重新考慮一些問題，這些只是新的冠狀病毒的 問世，世界衛生組織最近將其 更名為 Covid-19。
照片：GovHk。
在商店和在線商店（如果尚未售罄），有各種等級，材料，樣式和品種的各種口罩：醫用紙製成的口罩，彩色彩虹裝飾紙口罩，光滑的聚氨酯皮塔膜口罩，可洗織物口罩以及可重複使用的防塵防過敏口罩。這些產品中的大多數絕對沒有針對新型冠狀病毒或其他病毒的保護。
哪些口罩可以提供保護？手術口罩和N95呼吸器，可從空氣中過濾病毒，效率高達95％；即使病毒小於過濾器空間，它們也被捕獲在掩模層中並通過離子結合到過濾器材料上。但是，即使是最好的口罩，也常常會被戴錯並處理不當，市場上的許多口罩也是 假冒產品。
香港的市場相對不受監管，廣告宣傳的許多口罩，尤其是在網上銷售的口罩，誇大其詞或完全是虛假的，然而，針對諸如冠狀病毒之類的恐怖疾病的保護措施卻令人們感到恐懼，並打開了錢包。結果，許多人最終購買了錯誤的口罩或不正確地佩戴好口罩，而復合濫用可能有助於傳播而不是預防危險的呼吸道病原體，例如Covid-19。戴上口罩的用戶可能會誤以為是安全感，可能會進入高風險區域，使自己面臨更多的冠狀病毒危險，並繼續以指數方式感染其他人。
常見口罩使用錯誤
讓我們看一下有關使用口罩的一些常見問題：
- 口罩只能面朝下戴在鼻子上，不能拉到下巴下面，也可以只戴在嘴上，露出鼻子。如果佩戴不當，即使最好的口罩也無法保護。
照片：湯姆·格倫迪/香港FPFP。
- 將面罩拉到下巴下面進行交談或進食，然後再次將面罩放回原處。
- 重複使用或回收口罩。自2020年1月以來，這一直是香港常見且危險的新興做法。
- 戴同一口罩時間過長。可以安全佩戴口罩的時間長短取決於用戶周圍的人數。面罩的外層是最終的屏障。就像漁網一樣，它不僅可以過濾，而且可以積聚病原體，而不會使其滅活或殺死。口罩在其他人身上戴的時間越長，感染力就越集中。口罩的佩戴時間不得超過一天。在一次輪班中，醫生或護士會戴上多個口罩。
- 使用過的口罩不能快速，適當地丟棄。用過的口罩會積聚潛在的感染性微粒，其中可能包括冠狀病毒和其他病原體，如果保留下來，它們會交叉污染以前的清潔區域。
- 使用偽造的口罩。外科口罩的金標準是ASTM-F2100。但是有許多看起來相似的口罩，是由不符合該標準的廉價材料製成，並且沒有提供足夠的防病屏障。只向信譽良好的賣家購買；由不合格材料製成的口罩在網上比比皆是。
- 依靠N95口罩。如果佩戴正確，這些呼吸面罩的內部會很熱，並且 很難呼吸 由於內部和外部大氣之間的壓力變化。這就像通過毯子呼吸一樣，可能會使用戶感到困擾。如果正確和長期使用，使用者的血氧飽和度會下降，二氧化碳會顯著增加。即使正確健康的成年人，如果正確戴上N95，一小時左右的使用後仍會感到困難。老年人或免疫功能低下的人使用N95面罩可能會很困難，即使很短的時間。穿戴者可能會暫時將其摘下，這會降低其防護性。由於窒息的風險較高，因此兒童和嬰兒通常也不適合佩戴N95。
避免戴口罩
現在，讓我們看看人們在這些絕望而令人困惑的時代里為避免Covid-19而戴的其他口罩：
- 選擇由織物，紙張或塑料製成的劣質口罩，或防塵或防過敏口罩，並將其戴在高風險區域。
照片：Stand News。
- 帶有“ N95插入物”的Pitta面罩。皮塔（Pitta）口罩由多孔海綿材料製成，除小圓形閥門插入件外，整個口罩均不過濾。
- 用水果，雨衣，女性內衣，紙板箱，塑料瓶和其他家居用品製成的自製口罩和麵罩。這些沒有提供針對冠狀病毒的保護，並且對於絕望者僅賦予錯誤的安全感。
最近，《南華早報》援引香港大學的研究，發表了 自己動手做的指南 ，內容是使用紙巾和膠帶在家中製作口罩。該文章聲稱，這些自製的口罩可為製造的口罩提供80-90％的保護。實際上，這是一種非常不安全的做法，也是不負責任的公眾指導。
除了必須進行過濾，細菌，液滴，壓力，飛濺和可燃性測試外，適當的外科口罩還必須經過測試才能確保其美國食品藥品監督管理局（FDA），美國材料試驗學會（ASTM）或國際組織標準化（ISO）分類和批准，必須強調的是，醫用級手術口罩的任何部件都不由紙製成。外科口罩由三到四層組成-包括紡粘或熔噴聚丙烯（過濾層），聚丙烯纖維素/聚酯的高密度非織造層以及朝向玻璃的熔噴聚丙烯過濾材料層臉側。
如果您沒有真正的口罩，最好保持與他人的安全距離，與他人孤立，並保持良好的手部衛生，直到我們對Covid-19有了更好的了解。
根據世界衛生組織的說法，在 不合適的時候戴上醫用口罩不僅會導致不必要的花費，還會使使用者感到不安全感。勤洗手和不觸摸臉部等習慣可能會更好地預防冠狀病毒。但是，香港的 每平方公里人口密度是全球 最高的。幾乎不可能避免擁擠的地方，距離任何人至少2至3米，更不用說避免緊密接觸的咳嗽或打噴嚏了。最好的選擇是呆在家裡。好玩的不是嗎？
如何選擇好口罩
針對這些警告，如果您仍然堅持戴口罩，應該選擇哪種類型？在社交和學術界的辯論中，人們在線討論在呼吸道病原體（如冠狀病毒）爆發期間使用外科口罩的有效性。但是，已證明正確使用外科手術或N95口罩配合勤勤洗手可減少呼吸道疾病的傳播。
檔案照片：Kaiser /聯合社會出版社。
儘管已經對外科口罩和呼吸器進行了數十年的研究，但在醫院，外科手術條件和大流行中，有關其實際用途的問題仍然很多。對研究文獻（例如《美國醫學會雜誌》）的系統評價 表明，正確佩戴的外科口罩和N95呼吸器彼此等效。但是，考慮到現實生活中用戶使用N95防毒面具的困難，最適合消費者使用的是ASTM-F2100外科口罩。
提供可靠保護的質量口罩已得到國際監管機構（例如ASTM，FDA或NIOSH）的批准和驗證，並在包裝上帶有相應的認證代碼。為了防止假面具，建議購買者尋找信譽良好的賣家，這些賣家提供諸如金伯利·克拉克（Kimberly Clark）或3M之類的可信賴品牌。
最近，公司開始提供外科手術和N95口罩，這些口罩具有嵌入常規過濾層中的新型抗病毒和抗菌成分。這種面罩是由香港一家名為Filligent Limited的小型公司開發的，2012年，它被美國FDA授予“同類首創”的批准。（全部披露：我曾擔任研發總監，負責Filligent的FDA對該面膜的批准，但我與現在擁有生產和銷售其權利的公司沒有當前或持續的財務利益或與之有僱傭關係。）
香港人排隊戴口罩。檔案照片：湯姆·格倫迪（Tom Grundy）/香港電影節。
這種抗病毒外科口罩在所有方面都等同於醫院和從業人員使用的正常ASTM-F2100外科口罩。因為外層是親水性的，所以它吸收了打噴嚏和咳嗽的飛沫，並且外層中的化合物可以滅活各種呼吸道病毒。該面罩針對15種以上的A型和B型流感病毒以及豬，馬和禽流感病毒進行了測試，所有菌株均具有99.99％的失活率。他們還致力於滅活其他呼吸道和其他常見細菌病原體。
與標準外科口罩相比，這些稱為BioMask的口罩可以長時間佩戴。由於外層中的抗病毒化合物，消除了外科口罩可能發生的交叉污染問題。這些口罩已與CURAD和Medline以及Target的“ Up＆Up”自家品牌聯合使用，可在北美的CVS，Walgreens和Target購得。但是，自2019年12月以來，這些抗病毒口罩以及常規外科口罩的供應一直稀缺。
戴外科口罩的正確方法
第一步是檢查面罩。如果損壞，則將其丟棄。
如果面罩看起來還不錯，請拉動耳朵周圍的環，將面罩擴展到鼻子和下巴，並確保其貼合舒適。戴上，戴上或摘下口罩時，請勿觸摸口罩的表面。
如果口罩的內部（佩戴者）或外部（通過公共暴露）沾有體液，請更換面罩。但是，一般而言，口罩是一次性使用的物品，切勿被回收或再利用。只能通過觸摸耳掛來去除面罩，以免手指交叉污染。正確包裝並處理好口罩，然後洗手。
我們從這一切中學到什麼？
香港面罩的短缺是一個恥辱。在2003年“非典”危機過後，香港政府應為冠狀病毒等傳染性疾病撥款，並儲備足夠的口罩和其他專業PPE（個人防護設備），以保護公共衛生工作者和工作面的其他人員，例如：作為醫生，醫院員工，機場工作人員和環衛工人。
這讓我們問：除了對如何正確選擇，佩戴和處置口罩方面的知識有所了解之外，您還可以做些什麼來保護自己和親人免受Covid-19的襲擊？正如世界衛生組織指出的那樣，僅口罩不足以預防冠狀病毒。
確保也 經常 用肥皂和清水洗手。這比任何種類的抗菌手凝膠都優越，因為它只需清除細菌，就可以完全清除手中的病原體-您最活躍的身體部位。當沒有肥皂和水時，請使用基於酒精的洗手液。確保使用硬幣大小的凝膠，並充分遮蓋您的手和指尖。
圖片：香港政府一站通。
實行社會疏離。在這個社交媒體時代，Skype和Zoom，在這個關鍵時刻應該只有特殊情況才能舉行面對面會議。 將鞋子放在 家裡。經常用稀釋的漂白劑或70％的酒精凝膠清洗經常接觸的高流量物品，例如門把手和電梯按鈕。避開電梯上樓梯！
傳染病專家一致認為，隨著人類繼續侵犯自然生態系統，傳染性疾病的爆發將變得越來越普遍。 未來十年，全球人口將再增長 10億，因此埃博拉病毒，SARS，MERS，Marburg和Covid-19只是標誌著一系列新的嵌合人畜共患病毒的出現。假設接下來將要發生的任何疾病都不會同樣地影響我們，這是愚昧無知的。他們來了，這僅僅是我們何時以及如何能夠智能地保護自己的問題。
這篇文章首先出現在Forkast.News上。Ariane Davison博士是香港的病毒免疫學家，也是全球衛生保健顧問的總監。她在全球醫療保健，生物技術，新興，諮詢和股票行業擁有豐富的經驗，在香港，中國和美國的諮詢和資產管理領域擔任高級職務。在其他成就中，她於2011年領導了一個研究小組，該研究小組獲得了美國食品和藥物管理局“一流”醫療器械批准的ASTM抗菌和抗病毒面罩認證。Davison獲得了博士學位。悉尼大學醫學博士學位，並發表在期刊和教科書上。
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美國衛生局局長surgeon general週六警告說，口罩不能有效防止普通人感染冠狀病毒。民眾搶買口罩, 會造成市場缺貨，反而會對公共衛生專業人員有害。
紐約時報：The surgeon general on Saturday warned that masks were not effective in preventing the general public from contracting the coronavirus.
Surgeon General Urges the Public to Stop Buying Face Masks
“Seriously people,” the surgeon general said on Twitter, warning that a run on the masks could risk a shortage harmful to public health professionals.
"They are NOT effective."
The FDA gave the green light to rapidly expand virus testing in the U.S.
BLOOMBERG.COM
U.S. Surgeon General Urges People to ‘Stop Buying Masks’
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