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Because of the fast-spreading Delta variant, health officials are renewing calls for people to wear face masks — even if they're fully vaccinated against COVID-19. Last week we told you that if anything looked likely to roll back our newfound pandemic freedoms, it was the Delta variant. Sure enough, it is. On Monday, the Los Angeles County Department of Public Health advised all residents to wear masks while they’re in public indoor spaces — even if they’re fully vaccinated against COVID-19. It may seem like a mixed message. After all, the county reminded people that “fully vaccinated people appear to be well protected from infections with Delta variants.” And as far as scientists can tell, that appears to be true. But no vaccine is perfect. The county has confirmed at least 10 coronavirus infections involving the Delta variant among people who were fully vaccinated. None required hospital care, most likely thanks to the immune-system boost they got from the vaccine.
The Delta variant, which was first identified in India, has also been found in three county residents who were partially vaccinated and 110 who were unvaccinated. These are the people health officials are most worried about. Scientists estimate that Delta is 60% more transmissible than the Alpha variant from the United Kingdom, which in turn is 50% more transmissible than the original coronavirus strain. That means Delta spreads more than twice as readily as the version of the virus that sparked the global pandemic. Among coronavirus samples sequenced in the U.S. in the two-week period that ended June 5 (the most recent reporting period available), 10% were Delta, according to the Centers for Disease Control and Prevention. In the prior two weeks, this variant accounted for just 2.9% of samples sequenced. In addition, by June 5, Delta made up nearly 35% of samples analyzed in Iowa, Kansas, Missouri and Nebraska, and 25% of those in Colorado, Utah, Montana, Wyoming and the Dakotas. In California, Delta accounts for 14.5% of coronavirus samples that have been sequenced so far in June, making it the third-most common variant in the state. With that in mind, asking everyone to wear masks in supermarkets, movie theaters, offices, retail stores and other indoor venues sounds like a way to be safe instead of sorry.
“Until we better understand how and to who the Delta variant is spreading, everyone should focus on maximum protection with minimum interruption to routine as all businesses operate without other restrictions, like physical distancing and capacity limits,” L.A. County officials explained in a statement. L.A.’s advice aligns with that of the World Health Organization, which advises people to “wear a mask, especially in crowded, closed and poorly ventilated settings,” even after they’ve been vaccinated. The CDC, on the other hand, still says people who’ve been fully vaccinated don’t need to wear masks or worry about social distancing. It’s unclear if Delta will prompt officials here to reinstate other safety measures for those who are vaccinated. Even if coronavirus spread accelerates, California’s vaccine coverage is high enough to prevent another devastating surge. (Contrast that with South Africa, where less than 1% of the population is vaccinated. The Delta variant is fueling a third wave of infections there that’s on track to top the previous two, prompting President Cyril Ramaphosa to impose a sweeping set of new restrictions that includes a ban on indoor and outdoor gatherings, earlier curfews for nonessential businesses and the suspension of leisure travel in and out of the country’s most populous province.) But the more a virus spreads, the more chances it has to mutate. And the more it mutates, the more chances it gets to acquire a genetic change that reduces the efficacy of vaccines or medicines. “It’s quite simple: More transmission, more variants. Less transmission, less variants,” WHO Director-General Tedros Adhanom Ghebreyesus said Friday. “That makes it even more urgent that we use all the tools at our disposal to prevent transmission.”
Short of a total lockdown, universal mask-wearing is the most effective way to slow the relentless rise in hospitalizations and deaths from Covid-19. As a professional health writer and concerned citizen, the ache in my heart deepens with each new report of the devastation wrought by the novel coronavirus, the cause of immeasurable — and still increasing — personal and economic pain for people caught in its deadly spikes. In a recent five-week period, 100,000 Americans died from complications of Covid-19, a toll that took the country four months to reach last spring. My distress is magnified by the knowledge that it didn’t have to be this bad. One simple measure — consistent wearing of face coverings in public — could have helped to stem the agony. In December, the Centers for Disease Control and Prevention reiterated advice first given in July: “Wear a mask over your nose and mouth. Everyone should wear a mask in public settings and when around people who don’t live in your household, especially when other social distancing measures are difficult to maintain.” Masks, the agency emphasized, protect both the wearer and those the wearer encounters in the course of daily life. Now, with the emergence of a highly contagious variant of the virus and the chaotic attempts to distribute and administer vaccines to hundreds of millions of vulnerable Americans, short of a total lockdown, universal mask-wearing is the most effective way to slow the relentless rise in hospitalizations and deaths from Covid-19.
It will take many months to immunize everyone willing and able to get a Covid vaccine. Meanwhile, we’re facing another tsunami of deadly coronavirus infections as the new variant sweeps through swaths of still-unprotected millions As with many other measures not taken by the last administration to minimize the spread of Covid-19, mask-wearing was left up to the states to mandate and enforce. Masks became a political football, and the former president publicly ridiculed opponents who wore them. Some elected officials even made the ridiculous, baseless claim that masks not only don’t thwart the spread of the virus, they actually enhance it. I wonder if they also ignored parents and teachers who told them to cover their mouths when they coughed or sneezed. I also wonder about the economic savvy of our former president and the governors who have resisted issuing mask mandates, some of whom got Covid-19 themselves yet clamored to open the economy. Goldman Sachs estimated last June that implementing a nationwide mask mandate could have a potential impact on the U.S. GDP of one trillion dollars. Lately, as I await my second vaccine shot, I’ve become increasingly aware of how many people walk, run or cycle without a mask or, if they have a mask, wear it ineffectively. I’ve taken to speaking up more often: “Please wear your mask” or “The mask should cover your nose and mouth.” Among the ignorant responses: “I don’t need a mask when I’m outside,” “I already had Covid so I can’t get it again or give it to you,” and my favorite while walking on a four-foot-wide path, “I stay six feet away from people.” Although six-foot social distancing is not totally arbitrary, it’s based on limited evidence among airline passengers and may not apply at all, for example, to the unmasked cyclists shouting to one another as they ride past me or to the heavy-breathing runners I pass.
I’ve also heard a few people say, “I already got the vaccine, so I don’t need a mask.” This may be the most dangerous excuse of all. First, although the vaccines are very good, they’re not perfect, and chances are these vaccine recipients haven’t been checked for strong antibodies to the virus. Second, we don’t yet know if the vaccines, while highly effective in preventing sickness and death, will also prevent asymptomatic infection that can spread the virus to others. As Jeremy Howard, a data scientist at the University of San Francisco, said of mask refusers: “How would you feel if you made your best friend sick, or killed your friend’s mother?” Last February, after the World Health Organization, with no supporting data, advised against wearing a mask unless you were already sick, Mr. Howard amassed an international team of 19 scientists to review the evidence for mask-wearing, expecting to find “that masks were a waste of time,” he said in an interview. Instead, he said, the team found that “the data on the benefit of masks is really compelling.” The results of their exhaustive study were published recently in PNAS, the peer-reviewed Proceedings of the National Academy of Sciences. Mr. Howard said that preliminary reports of their findings resulted “in all sorts of abuse, including death threats” from mask resisters. But that has not kept him from repeating that “wearing any kind of mask will greatly help to keep you from accidentally infecting others, which is important for the community and the economy. About half of coronavirus infections are spread by people who don’t know they’re sick, and the new variant is much more transmissible.”
A Chinese study found that the viral load in the upper respiratory tracts of infected people without symptoms can be just as high as those with symptoms, and simply talking and breathing can spread virus-laden droplets and aerosols. And because the virus resides in high amounts in the nose and throat, sneezing can spew an infectious cloud 10 or more times further than coughing. Which brings me to the question of whether the face coverings most people use are sufficiently protective. I now know that the bandannas, exam masks and the slim neoprene masks I’ve been using for the last 11 months are better than nothing but not very good. They provide too many routes for virus-carrying particles to reach an unsuspecting nose or mouth. I should have followed the advice my colleague Tara Parker-Pope offered months ago on upgrading your mask. “Masks,” Mr. Howard said, “need a nose wire to provide a close fit and proper filtration material, like a nanofiber, that filters very small particles.” He and his co-authors concluded that for most of us, KN95 masks, especially those with bands that fit around the head, are currently the best to prevent contracting and spreading the virus. Another option is the KF94 mask or, if it’s not too uncomfortable, doubling up on masks for added protection. KN95 masks meet foreign certification standards and are designed to filter out 95 percent of particles down to 0.3 microns in size. (The gold standard N95 masks, which meet U.S. certification standards, should be reserved for health care and emergency personnel who are most likely to interact with Covid-infected individuals.) Powecom KN95 masks have an emergency use authorization from the Food and Drug Administration. I just ordered a packet of 11 on Amazon for $23.80 and I expect to be using them for many months after I’m vaccine-protected. I might still be able to transmit the virus and I want to set a good example for my fellow citizens.
See also research recently published in PNAS (Jan. 8, 2021):
Wearing a mask can help protect you, not just those around you, from coronavirus transmission, the CDC said in new guidance Tuesday. The statement was an update to previous guidance suggesting the main benefit of mask wearing was to help prevent infected people from spreading the virus to others. Cloth masks act as "source control" to block virus particles exhaled by the wearer and provide "filtration for personal protection" by blocking incoming infectious droplets from others, the CDC said in its new guidance. The new guidance cites a number of studies showing that masks reduce the risk of transmitting or catching the virus by more than 70% in various instances. One study revealed mutual mask-use helped prevent two infected hair stylists from transmitting the virus to 67 clients who were later interviewed. Another followed infected people who spent more than 10 hours on flights without infecting other passengers when masks were used. In several scenarios, when officials told people to wear masks, infections and deaths fell significantly, the CDC pointed out.
"Adopting universal masking policies can help avert future lockdowns, especially if combined with other non-pharmaceutical interventions such as social distancing, hand hygiene, and adequate ventilation," the CDC said. The agency cited an economic analysis that found a 15% increase in universal masking could prevent losses of up to $1 trillion. "The relationship between source control and personal protection is likely complementary and possibly synergistic, so that individual benefit increases with increasing community mask use," the CDC said. Some cloth masks are nearly as good as surgical masks at blocking droplets, the CDC said. Polypropylene may generate a static charge that captures particles, the CDC said, while silk might repel moist droplets and be more comfortable. "Multiple layers of cloth with higher thread counts have demonstrated superior performance compared to single layers of cloth with lower thread counts, in some cases filtering nearly 50% of fine particles less than 1 micron," the CDC said. "It's a two-way street," Dr. Anthony Fauci, National Institute of Allergy and Infectious Diseases director, said Tuesday on MSNBC. "You protect others, their mask protects you, and your mask also protects you."
Mandates for mask use in public during the recent COVID-19 pandemic, worsened by global shortage of commercial supplies, have led to widespread use of homemade masks and mask alternatives. It is assumed that wearing such masks reduces the likelihood for an infected person to spread the disease, but many of these mask designs have not been tested in practice. We have demonstrated a simple optical measurement method to evaluate the efficacy of masks to reduce the transmission of respiratory droplets during regular speech.
In proof-of-principle studies, we compared a variety of commonly available mask types and observed that some mask types approach the performance of standard surgical masks, while some mask alternatives, such as neck fleece or bandanas, offer very little protection. Our measurement setup is inexpensive and can be built and operated by non-experts, allowing for rapid evaluation of mask performance during speech, sneezing, or coughing.
Original study published in Science Advances (August 7, 2020):
Dr. Martin Fischer, from Duke University, developed a simple, low-cost technique to visualize the effectiveness of different face coverings on droplet emissions during normal wear. Testing several face coverings, the researchers found that the particles can be blocked by some, but not all recommended face coverings.
N95s without valves, and surgical, and polypropylene masks worked best. Cotton face coverings provided some coverage. Bandanas and neck fleece didn’t block the droplets very much, and indeed the "filter" smaller droplets that remained longer airborne. The experiments clearly shows the importance of wearing masks to prevent spreading of droplets that cary the COVID-19 virus, and also suggest that some face covers don 't do the job at all.
See also original study in Science Advances (August 7, 2020):
The new rule comes as France starts lifting its coronavirus lockdown on Monday. It has reignited a debate over a 2010 ban on religious face coverings. From Monday, all people in France must now wear a face mask in public to avoid further spread of the COVID-19 disease. However, the burqa, niqab, and other religious face and head coverings remain banned — reigniting a debate over the government's 2010 ban on religious coverings.
France mandated face masks in public to coincide with a gradual easing of its strict coronavirus lockdown, which started Monday. Under these new rules, people can now travel 60 miles from home, and some businesses and schools can reopen. However, bars and restaurants — which have been closed on March 17 — remain shuttered. Those using public transport, entering certain shops, or attending schools must now wear a mask, the government said. The issue of face coverings is especially sensitive in France, and has been a major political issue on at least two occasions since the new millennium. In 2010, the government imposed a ban on Muslim head coverings, namely the burqa or niqab. Those in favor of the bill protected gender equality and women's dignity, and encouraged assimilation into secular French culture. Critics saw it as an attack on religious freedom.
Flouting the law can result in a 150-euro ($162) fine and/or participation in so-called French citizenship education. When asked whether the new coronavirus face mask regulations affected the 2010 law, France's interior ministry told The Washington Post: "Wearing a mask intended to prevent any risk of contagion by COVID-19 does not constitute a criminal offense."...
These simple experiments illustrate how wearing a mask can stop the spreading of germs. In the study petri plates containing media to grow bacteria are exposed to an individual wearing a surgical mask or not. Conditions tested include coughing, sneezing, talking and singing. The results are striking. Masks block the ejection of droplets that contain bacteria. Exposed petri plates appear full of bacterial colonies when exposed to an individual who is not wearing a mask.
Experiments also confirm the effect of social distancing, and demonstrate how the individual does not spread bacteria to plates exposed at a distance of 6 feet away from the source. Although these experiments evaluate bacterial contamination, the droplets that carry these germs can also transport viruses such as SARS-CoV-2.
A large study finds that precautions like social distancing and wearing face masks can reduce the risk of spreading coronavirus infections. he best practices for controlling an infectious disease like COVID-19 aren’t easy to follow—keeping six feet apart from others, wearing face masks in public, and, if you’re a health care worker, wearing shields to protect your eyes as well. But in a study published Monday in The Lancet, researchers provide the strongest evidence yet that these practices do indeed lower the risk of spreading the virus.
An international group of scientists, led by senior author Dr. Holger Schunemann, professor of clinical epidemiology and medicine at McMaster University in Ontario, Canada, analyzed 172 studies conducted in 16 countries that looked at the connection between social distancing, wearing masks, and wearing eye protection, and the risk of transmitting the virus. The studies included people with COVID-19 infections in addition to those with two other diseases caused by coronaviruses, SARS and MERS. The studies were observational, meaning that they tracked infection rates among people who practiced any of the aforementioned behaviors. Of the 172 studies, 44 (involving more than 25,000 participants) also included comparisons between those who followed the behaviors and those who did not. When it comes to social distancing, the analysis showed that, on average, the risk of getting infected when remaining 1 meter (a little more than 3 ft) from an infected person was about 3%, while staying less than 1 meter apart upped the risk to 13%. The further people stand away from one another, the lower their risk. In fact, the risk drops by half for every additional meter of distancing up to 3 meters (about 10 ft).
“What we tried to do was bring everything together and sort out what distance might be the most effective, rather than an arbitrary threshold,” says Schunemann. Based on how far respiratory droplets from coughs or sneezes generally travel, most public health policies currently recommend standing at least 2 meters (about 6.7 ft) apart in public areas, which the study findings support. “The virus doesn’t know what a meter is, or what six feet is,” says Schunemann. “What this evidence suggests is that two meters, or 6.7 feet, appears that it might be more protective than one meter or three feet.” The data also supported the benefits of eye shields for health care workers. The risk of infection among people who wore glasses, goggles or other face shields was 6% compared to 16% among those not wearing such protection...
Original study published in the Lancet (June 1, 2020):
We identified seasonal human coronaviruses, influenza viruses and rhinoviruses in exhaled breath and coughs of children and adults with acute respiratory illness. Surgical face masks significantly reduced detection of influenza virus RNA in respiratory droplets and coronavirus RNA in aerosols, with a trend toward reduced detection of coronavirus RNA in respiratory droplets. Our results indicate that surgical face masks could prevent transmission of human coronaviruses and influenza viruses from symptomatic individuals.
A study of 246 individuals with seasonal respiratory virus infections randomized to wear or not wear a surgical face mask showed that masks can significantly reduce detection of coronavirus and influenza virus in exhaled breath and may help interrupt virus transmission...
Our results indicate that aerosol transmission is a potential mode of transmission for coronaviruses as well as influenza viruses and rhinoviruses....... Our studies demonstrate detection of human seasonal coronaviruses in exhaled breath, including the detection of OC43 and HKU1 from respiratory droplets and NL63, OC43 and HKU1 from aerosols....We also demonstrated the efficacy of surgical masks to reduce coronavirus detection and viral copies in large respiratory droplets and in aerosols (Table 1b). This has important implications for control of COVID-19, suggesting that surgical face masks could be used by ill people to reduce onward transmission.......Indeed, we identified virus RNA in a small number of participants who did not cough at all during the 30-min exhaled breath collection, which would suggest droplet and aerosol routes of transmission are possible from individuals with no obvious signs or symptoms.
George Gao, head of the Chinese Center for Disease Control and Prevention, offers insights from the front. Chinese scientists at the front of that country’s outbreak of coronavirus disease 2019 (COVID-19) have not been particularly accessible to foreign media. Many have been overwhelmed trying to understand their epidemic and combat it, and responding to media requests, especially from journalists outside of China, has not been a top priority. Science has tried to interview George Gao, director-general of the Chinese Center for Disease Control and Prevention (CDC), for 2 months. Last week he responded.
Gao oversees 2000 employees—one-fifth the staff size of the U.S. Centers for Disease Control and Prevention—and he remains an active researcher himself. In January, he was part of a team that did the first isolation and sequencing of severe acute respiratory syndrome 2 (SARS-CoV-2), the virus that causes COVID-19. He co-authored two widely read papers published in The New England Journal of Medicine (NEJM) that provided some of the first detailed epidemiology and clinical features of the disease, and has published three more papers on COVID-19 in The Lancet. His team also provided important data to a joint commission between Chinese researchers and a team of international scientists, organized by the World Health Organization (WHO), that wrote a landmark report after touring the country to understand the response to the epidemic.....
Updated guidance from the US Centers for Disease Control and Prevention says people fully vaccinated against Covid-19 do not need to wear masks or practice social distancing indoors or outdoors, except in certain circumstances.
People fully vaccinated against Covid-19 do not need to wear masks or practice social distancing indoors or outdoors, except under certain circumstances, the director of the US Centers for Disease Control and Prevention announced Thursday. "If you are fully vaccinated, you can start doing the things that you had stopped doing because of the pandemic," Dr. Rochelle Walensky said during a White House Covid-19 briefing. "We have all longed for this moment when we can get back to some sense of normalcy." Calling it an "exciting and powerful moment," Walensky said the science supports the updated CDC guidance that "anyone who is fully vaccinated can participate in indoor and outdoor activities -- large or small -- without wearing a mask or physical distancing." She cited three studies -- one from Israel and two from the United States -- that show vaccines work. The Israeli study, which was published in the Journal of the American Medical Association, showed the vaccine was 97% effective against symptomatic Covid-19 and 86% effective against asymptomatic infection in over 5,000 health care workers. There have been reports of "breakthrough" infections among vaccinated people in the United States -- a small number among more than 117 million people in the United States who are now fully vaccinated. Walensky noted that "the resulting infection is more likely to have a lower viral load, may be shorter in duration, and likely less risk of transmission to others."
Walensky's announcement has a few caveats. She warned that people who are immune compromised should speak with their doctors before giving up their masks. The requirement to wear masks during travel -- on buses, trains, planes and public transportation -- still stands, Walensky said. Guidance for travel will be updated as science emerges. She also said that "the past year has shown us that this virus can be unpredictable, so if things get worse, there is always a chance we may need to make a change to these recommendations." People who develop Covid-19 symptoms, even those who are vaccinated, should put their mask back on and get tested, Walensky said. The science is clear, too, for unvaccinated people, Walensky said: "You remain at risk of mild or severe illness, of death, or spreading the disease to others. You should still mask and you should get vaccinated right away." But once someone is fully vaccinated -- two weeks after the final dose -- "you can shed your mask," she said.
Some people may choose to continue wearing masks even if they are fully vaccinated, and that's OK, federal Covid-19 response leaders said Thursday. "People have to make their own personal choice," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said during the White House Covid-19 briefing. "There's absolutely nothing wrong with an individual who has a certain level of risk aversion, as we know the risk is extremely low of getting infected whether you're indoors or outdoors. But there are those people who don't want to take that bit of a risk and there's nothing wrong with that and they shouldn't be criticized."
New guidance lists "universal wearing of face masks" as the first strategy to help stop the spread of the coronavirus. The CDC on Friday issued its strongest mask guidance yet during the COVID-19 pandemic, calling for "universal mask wearing" in all activity outside of one's home. The new recommendation comes at the end of a week when the U.S. saw its deadliest day of the pandemic so far, with more than 3,100 lives lost on Thursday alone. "Compelling evidence now supports the benefits of cloth face masks for both source control (to protect others) and, to a lesser extent, protection of the wearer," the report states. Other measures including physical distancing, avoiding nonessential or crowded indoor spaces, postponing travel, and more testing and contact tracing are also part of the strategy outlined in the report, which warns that "[t]he United States has entered a phase of high-level transmission."
The new guidance lists "universal wearing of face masks" as the first recommendation to help stop the spread of the disease. It says masks should be worn for all indoor activity outside of an individual's home, as well as during all outdoor activity when at least 6 feet of social distancing can't be maintained. It also recommends wearing masks in your own household if someone living there has tested positive for the virus or has potentially been exposed. The CDC says masks are essential because about 50% of coronavirus spread comes from people who are not showing symptoms. The report notes that "colder weather, more time spent indoors, the ongoing U.S. holiday season, and silent spread of disease" are all factors leading to the virus' explosion across the country. Another recent CDC update determined that masks help protect the person wearing one, in addition to other people. CDC Director Robert Redfield has said masks may be the most effective tool for fighting the pandemic, even more than a vaccine. Even as the U.S. sees a record-breaking rise in COVID-19 cases nine months into the pandemic, mask wearing remains a divisive issue. Some governors who initially opposed mask mandates issued them in November as hospitals filled near capacity, while others — including Florida's Republican Governor Ron DeSantis — still refuse to require masks or punish people who don't wear them. The latest CDC report recommends state and local leaders "issue policies or directives mandating universal use of face masks in indoor (nonhousehold) settings."
Updated CDC Guidelines Published in MMWR (Dec. 4, 2020):
Mask wearing might also be reducing the severity of the virus and ensuring that a greater proportion of new infections are asymptomatic. Face masks may be inadvertently giving people Covid-19 immunity and making them get less sick from the virus, academics have suggested in one of the most respected medical journals in the world. The commentary, published in the New England Journal of Medicine, advances the unproven but promising theory that universal face mask wearing might be helping to reduce the severity of the virus and ensuring that a greater proportion of new infections are asymptomatic.
The commentary, published in the New England Journal of Medicine, advances the unproven but promising theory that universal face mask wearing might be helping to reduce the severity of the virus and ensuring that a greater proportion of new infections are asymptomatic. It comes as increasing evidence suggests that the amount of virus someone is exposed to at the start of infection - the “infectious dose” - may determine the severity of their illness. Indeed, a large study published in the Lancet last month found that “viral load at diagnosis” was an “independent predictor of mortality” in hospital patients. Wearing masks could therefore reduce the infectious dose that the wearer is exposed to and, subsequently, the impact of the disease, as masks filter out some virus-containing droplets. If this theory bears out, researchers argue, then population-wide mask wearing might ensure that a higher proportion of Covid-19 infections are asymptomatic.
Better still, as data has emerged in recent weeks suggesting that there can be strong immune responses from even mild or asymptomatic coronavirus infection, researchers say that any public health strategy that helps reduce the severity of the virus - such as mask wearing - should increase population-wide immunity as well This is because even a low viral load can be enough to induce an immune response, which is effectively what a typical vaccine does. While this hypothesis needs to be backed up with more clinical study, experiments in hamsters have hinted at a connection between dose and disease. Earlier this year, a team of researchers in China found that hamsters housed behind a barrier made of surgical masks were less likely to get infected by the coronavirus. And those who did contract the virus became less sick than other animals without masks to protect them. Some observations found in humans seem to support this as well. In a coronavirus outbreak on a closed Argentinian cruise ship, for example, where passengers were provided with surgical masks and staff with N95 masks, the rate of asymptomatic infection was 81 per cent. This is compared with 20 per cent in earlier cruise ship outbreaks without universal masking.
Original Letter Published in NEJM (Sept. 8, 2020):
Instant Pot proves to be the most effective in sterilizing an N95 mask for reuse and killing the coronavirus compared to ultraviolet light. Yes, you read it right, the 7-in-1 'Instant Pot' used mostly for pressure and slow cooking, rice, and steaming can now be used to disinfect and sterilize an N95 mask killing the Novel coronavirus in less than 50 minutes, experts share. Daily Mail reports that researchers from the University of Illinois found that this kitchen equipment is useful in the kitchen and for other unconventional uses, most notably is its usage for sterilizing an N95 mask. The Instant Pot can disinfect and sterilize a mask, or more, using its standard cook function that runs for 50 minutes. This cook function produces 212 degrees Fahrenheit (100 degrees Celsius) that is said to be enough in killing the virus. Instant Pot uses "dry heat," making it ideal for disinfecting the mask, inside and out. N95 masks use materials including stretchable or garterized materials that lose their flexibility in the span of its use. Researchers list this as one of the concerns of the medical community that frowns on reusing said masks. The effectivity of the mask's filtration significantly reduces if components have reduced performance or functions compared to when it is brand new. This process enables users to safely reuse the mask, unlike the CDC's recommendation of using it for just an extended period. Researchers added that this process is more effective than using an ultraviolet light in sanitation.
This home remedy uses the "Instant Pot" that adds a new feature on its long list of functions, including pressure cooking, steaming, rice cooking, slow cooking, sauteing, yogurt making, and warming. Its unique and latest feature, sterilizing the deadly pandemic virus, COVID-19. The University of Illinois researchers exhibited the proper sterilization process in a YouTube video to help the medical community and even people who use the N95 masks for protection against the pandemic. Researchers advise people to put a towel on the Instant Pot's surface to avoid direct heat or contact on the body. The masks only need the heat to go "through and through" to effectively kill any virus, especially COVID-19, that occur the mask's surface and its filters inside. "Any sanitation method would need to decontaminate all surfaces of the respirator, but equally important is maintaining the filtration efficacy and the fit of the respirator to the face of the wearer," Vishal Verma, a researcher of the Insta Pot from the University of Illinois said. The team then tested the mask's fit and deemed that the Instant Pot method helps preserve it. This process helps in decontaminating the mask, maintain its component's integrity to ensure proper fit to the wearer's face, and overall sanitize the product...
Researchers can't agree on topics such face mask, immunity and number of infections. Here's why. Although political leaders have closed borders in response to COVID-19, scientists are collaborating like never before. But the coronavirus (SARS-COV-2) is novel – and we don’t yet have all the facts about it. As a result, we may have to change our approach as new scientific data comes in. That doesn’t mean the science isn’t trustworthy – we will get the full picture over time. And there is already great research that can help inform political decisions. Here are three topics that scientists disagree on.
Face masks
The novel coronavirus spreads by droplets from coughs, sneezes and speaking. To halt the spread of the virus, face masks have become compulsory in many countries.
But there has been much debate among scientists over the effectiveness of face masks on reducing the spread of COVID-19. A report from a multidisciplinary group convened by the Royal Society has come out in favour of the public wearing face masks. These documents, which have not been peer reviewed, argue that face coverings can contribute to reducing the transmission of COVID-19 if widely used in situations where physical distancing is not possible. One relatively small clinical study also showed that infected children who wore masks did not pass on the virus to family contacts. But the science is complex. Face masks won’t stop the wearer from inhaling small airborne particles of coronavirus, which can cause infection. A recent study reported that wearing a mask may also give a false sense of security, meaning wearers may ignore other important infection control measures. We also know that face masks can make us breathe more often and more deeply – potentiality spreading more contaminated air...
Immunity
Immunologists are working hard to determine what immunity to COVID-19 looks like. Much of the studies have focused on “neutralising antibodies”, produced by so-called B-cells, which bind to viral proteins and directly prevent infection.
Studies have found that levels of neutralising antibodies remain high for a few weeks after infection, but then typically begin to wane. A peer-reviewed study from China showed that infected people had steep declines in levels of antibodies within two to three months of infection. This has created doubt over whether people get long-term protection against subsequent exposure to the virus. If this study turns out to be accurate – the result needs to be backed up by other studies – it could have implications for whether it is possible to produce vaccines with long-lasting immunity. While many scientists believe antibodies are the key to immunity, others argue that other immune cells called T-cells – produced when the body encounters the molecules that combat viruses, known as antigens – are involved too. These can become programmed to fight the same or similar viruses in the future. And studies suggest that T-cells are at work in many patients fighting COVID-19. People never infected may also harbour protective T-cells because they’ve been exposed to similar coronaviruses. A recent study from Karonliska Institute in Sweden, which has not yet been peer reviewed, found that many people who suffered mild or asymptomatic COVID-19 have T-cell-mediated immunity – even when antibodies can’t be detected. The authors believe this can prevent or limit reinfection, estimating that one-third of people with symptomless COVID-19 could have this kind of immunity. But it is not clear yet how it works and how long it lasts...
Number of cases
The reporting of coronavirus cases varies drastically around the world. Some regions are reporting that less than 1% of people have been infected, and others that over half the population has had COVID-19. One study, which has been peer reviewed, estimated that only 35% of symptomatic cases have been reported in the US, and that the figure is even lower for some other countries. When it comes to estimating true prevalence, scientists use just one of two main approaches. They either test a sample of people in a population for antibodies and directly report those numbers, or predict how the virus has affected a population using mathematical models. Such models have given very different estimates...
Updated projections (July 7) by the Institute of Health Metrics and Evaluation (IHME), now estimate over 208,000 total deaths in the United States by November first. These new numbers estimate 75,000 additional deaths will occur in the following 4 months. The model predicts that up to 40,000 deaths can be avoided by implementing universal wearing of face masks in the U.S. The model forecasts 600-700 daily deaths in the U.S. through the summer, later increasing as we enter into the flu season.
By comparison, under easing mandates, near 1300 average daily deaths are predicted by November in the U.S. The model also estimates significant burden of disease in Brazil, with 176,000 cumulative deaths by the first of November.
We have elucidated the transmission pathways of coronavirus disease 2019 (COVID-19) by analyzing the trend and mitigation measures in the three epicenters. Our results show that the airborne transmission route is highly virulent and dominant for the spread of COVID-19. The mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the trends of the pandemic. This protective measure significantly reduces the number of infections. Other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public. Our work also highlights the necessity that sound science is essential in decision-making for the current and future public health pandemics...
Here we show that airborne transmission is highly virulent and represents the dominant route to spread the disease. By analyzing the trend and mitigation measures in Wuhan, China, Italy, and New York City, from January 23 to May 9, 2020, we illustrate that the impacts of mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the pandemic trends in the three epicenters. This protective measure alone significantly reduced the number of infections, that is, by over 78,000 in Italy from April 6 to May 9 and over 66,000 in New York City from April 17 to May 9. Other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public. We conclude that wearing of face masks in public corresponds to the most effective means to prevent interhuman transmission, and this inexpensive practice, in conjunction with simultaneous social distancing, quarantine, and contact tracing, represents the most likely fighting opportunity to stop the COVID-19 pandemic. Our work also highlights the fact that sound science is essential in decision-making for the current and future public health pandemics.
Aerosols and droplets generated during speech have been implicated in the person-to-person transmission of viruses, and there is current interest in understanding the mechanisms responsible for the spread of Covid-19 by these means. The act of speaking generates oral fluid droplets that vary widely in size, and these droplets can harbor infectious virus particles. Whereas large droplets fall quickly to the ground, small droplets can dehydrate and linger as “droplet nuclei” in the air, where they behave like an aerosol and thereby expand the spatial extent of emitted infectious particles. We report the results of a laser light-scattering experiment in which speech-generated droplets and their trajectories were visualized...
When a person spoke through the open end of the box, droplets generated during speech traversed approximately 50 to 75 mm before they encountered the light sheet. An iPhone 11 Pro video camera aimed at the light sheet through a hole (7 cm in diameter) on the opposite side of the box recorded sound and video of the light-scattering events at a rate of 60 frames per second. The size of the droplets was estimated from ultrahigh-resolution recordings...
We found that the number of flashes increased with the loudness of speech; this finding was consistent with previous observations by other investigators.3 In one study, droplets emitted during speech were smaller than those emitted during coughing or sneezing. Some studies have shown that the number of droplets produced by speaking is similar to the number produced by coughing.
Es importante para tomar las medidas preventivo-promocionales conocer el o los modos de transmisión del agente patógeno. el coronavirus es un agente patógeno que se conoció muchas de sus caracteristica en el camino.
BBLIOGRAFIA:
5. Pollit KJG. Vulnerabilidad de COVID-19: el impacto potencial de la susceptibilidad genética y la transmisión aérea. Hum Genomics [Internet]. 2020 [citado el 12 de octubre de 2020]; 14:1-7. Disponible en: Disponible en: https://link.springer.com/content/pdf/10.1186/s40246-020-00267-3.pdf [ Enlaces ]
Some argue that masking everyone would slow the spread of COVID-19—but the evidence is spotty. As cases of coronavirus disease 2019 (COVID-19) ballooned last month, people in Europe and North America scrambled to get their hands on surgical masks to protect themselves. Health officials jumped in to discourage them, worried about the limited supply of masks for health care personnel. “Seriously people-STOP BUYING MASKS!” began a 29 February tweet from U.S. Surgeon General Jerome Adams. The World Health Organization and U.S. Centers for Disease Control and Prevention (CDC) have both said that only people with COVID-19 symptoms and those caring for them should wear masks.
But some health experts, including the director of the Chinese Center for Disease Control and Prevention, think that’s a mistake. Health authorities in parts of Asia have encouraged all citizens to wear masks in public to prevent the spread of the virus, regardless of whether they have symptoms. And the Czech Republic took the uncommon step last week of making nose and mouth coverings mandatory in public spaces, prompting a grassroots drive to hand make masks. Even experts who favor masking the masses say their impact on the spread of disease is likely to be modest. Many are also afraid to promote mask buying amid dire shortages at hospitals. But as the pandemic wears on, some public health experts thinkt government messages discouraging mask wearing should shift. “It’s really a perfectly good public health intervention that’s not used,” argues KK Cheng, a public health expert at the University of Birmingham. “It’s not to protect yourself. It’s to protect people against the droplets coming out of your respiratory tract.”
Cheng and others stress that however masks are used, people must practice social distancing and stay at home as much as possible to prevent the spread of the novel coronavirus. When people do venture out and interact, they’re likely to spew some saliva. “I don’t want to frighten you, but when people speak and breathe and sing—you don’t have to sneeze or cough—these droplets are coming out,” he says....
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