- The dangerous idea being propagated by many that social distancing of between 1 to 3 meters based that droplets "hit a virtual wall and stop there and after that we are safe," is not based on evidence found in her research.
- JAMA Insights | March 26, 2020: Turbulent Gas Clouds and Respiratory Pathogen Emissions
- The Centers for Disease Control and Prevention recommends a 6-foot (2-m) separation.7,8
BREAKING NEWS! Covid-19 Prevention:
New Study Proves That Social Distancing Of 1 to 3 Meters Is Nothing But Fake News and Misinformation
Covid-19 Prevention: Many are still wondering who is the charlatan who came the idea that social distancing of 1 to 3 meters would suffice to prevent the spread of the SARS CoV-2 coronavirus despite no official scientific studies to show that it true and is fully safe.
To make matters worse, since the beginning of this Covid-19 breakout, we have allowed government authorities, health officials, unreliable medical experts and academics, social media platforms and search engines and also health organizations to get away with fake news and misinformation. Many of these ignorant charlatans have been advocating social distancing and misleading the public that it is safe as long as distances of between 1 to 3 meters is maintained although there are no supporting scientific studies to say it works.
We at Thailand Medical News have always favoured stringent lockdowns, self-isolation, frequent testing as the main strategies to curtail the spread. Now with more studies emerging that social distancing really does not work, we strongly advocate that individuals and the public worldwide start taking legal actions and class suits against all sites, experts and authorities advocating social distancing of between 1 to 3 meters as these ignorant buffoons are actually endangering the lives of many.
A new research by qualified experts in their field from the MIT (Massachusetts Institute of Technology) lead by Dr Lydia Bourouiba, an Associate Professor at MIT, have researched the dynamics of exhalations (coughs and sneezes, for instance) for years at The Fluid Dynamics of Disease Transmission Laboratory and found exhalations cause gaseous clouds that can travel up to 27 feet (8.2 meters).
The new research is published in the Journal of The American Medical Association (JAMA). DOI: 10.1001/jama.2020.4756
The new research could have implications for the global Covid-19 pandemic, though measures called for by the Centers for Disease Control and Prevention and the World Health Organization call for six and three feet (0.9 m and 1.8 m) of space, respectively.(It should be noted that The WHO from day one has failed to prevent the global spread of the Covid-19 that originated from China plus they were the very same entity that advocated no border closures and no stopping of travel along with a lot of other misinformation that have resulted in the predicament that the world is in and yet no one has started any actions against any of these individuals while the US CDC is the hopeless entity that messed up on the diagnosing criteria and also on arranging of sufficient test kits that has resulted in the mess that the United Sates is in today yet no one from the entity has done the right thing of stepping down due to their incompetency. The American public and the world should never forget these two entities and the names and individuals associated.)
Dr Bourouiba told Thailand Medical News, "There's an urgency in revising the guidelines currently being given by the WHO and the CDC on the needs for social distancing and also protective equipment, particularly for the frontline health care workers.”
Dr Bourouiba's research calls for better measures to protect health care workers and, potentially, more distance from infected people who are coughing or sneezing. She said current guidelines are based on "large droplets" as the method of transmission for the virus and the idea that those large droplets can only go a certain distance.
In the research study, Bourouiba said peak exhalation speeds can reach 33 to 100 feet per second (36 km/h and 110 km/h) and "currently used surgical and N95 masks are not tested for these potential characteristics of respiratory emissions."
The dangerous idea being propagated by many that social distancing of between 1 to 3 meters based that droplets "hit a virtual wall and stop there and after that we are safe," is not based on evidence found in her research, Dr Bourouiba said, and also not based on "evidence that we have about COVID transmission."
Dr Bourouiba argued that a "gaseous cloud" that can carry droplets of all sizes is emitted when a person coughs, sneezes or otherwise exhales. The cloud is only partially mitigated by sneezing or coughing into your elbow.
She added, "In terms of the fluid regime on how the exhalations are emitted, the key point that we have shown is that there's a gaseous cloud that carries droplets of all sorts of sizes, not 'large' versus 'small' or 'droplets' versus 'aerosols.'"
Professor Dr Paul Pottinger, an infectious disease expert at the University of Washington School of Medicine, said questions remain about the distances at which the virus is effective.
He said, "For me, the question is not how far the germs can travel, but how far can they travel before they're no longer a threat. The smaller the germ particles, the lower the risk that they might infect somebody who would breathe them in or get them stuck in their nose or their mouth.”
He added, "The biggest threat we think with the coronavirus is actually the larger droplets. Droplets of saliva, snot, spit. Droplets that almost look like rain, if you will, when someone sneezes. Those droplets are large enough that gravity still acts on them. Usually, within about six feet of leaving somebody's body, those larger, more infectious droplets will drop to the ground. That's where the six-foot rule comes from. But it is the smaller and minute droplets that can be propelled by air and wind that is off a concern"
When questioned about this new study, the hopeless World Health Organisation (WHO) referred to a recent scientific brief on the methods of transmission, which recommended "droplet and contact precautions for those people caring for COVID-19 patients." The CDC did not respond to an emailed request for comment.
WHO however said later in a statement, "WHO carefully monitors emerging evidence about this critical topic and will update this scientific brief as more information becomes available. WHO welcomes modeling studies, which are helpful for planning purposes. WHO teams work with several modeling groups to inform our work."
As the SARS-Cov-2 coronavirus were effective at ranges of up to 27 feet (8.2 meters), as Bourouiba contends in her research, Dr Pottinger said he believes more people would be sick and more could have been affected as a result of the previous misinformation.
He added, "It takes a certain number of viral particles, we call them 'virions,' or individual viruses, it takes a certain number of individual viruses to actually get a foothold inside the body and cause that infection to get going.”
He further added, "Now, we don't know exactly what that number is, but it's probably more than a single virus. But we do know that this SARS-CoV-2 virus travels very efficiently by air.”
Dr Bourouiba said she wants to see recommendations made based on current science not "policies based on supply, for example, because we don't have enough PPE (personal protective equipment)." It's well-known PPE is in short supply nationwide and health care workers have been desperately trying to find effective ways to deal with shortages.
She added, "Although there remains a lot of questions to be addressed about how much virus is at a given distance or not, we have no answer one way or another at this time. Therefore, the precautionary principle should drive the policies to state that we should have high-grade respirators used for health care workers."
She stressed, "Once that's decided, that's the thrust that's needed to now mobilize most effectively the kind of tremendous high production level that is possible to reach in a great country like the United States. This thrust is not happening."
Please share this article to as many of your friends and loved ones to save their lives.
For the latest on strategies of Covid-19 prevention, keep logging on to; Thailand Medical News.
https://www.thailandmedical.news/news/breaking-news-covid-19-prevention-new-study-proves-that-social-distancing-of-1-to-3-meters-is-nothing-but-fake-news-and-misinformation
PS: We do not apologise for the name calling nor apologise for lowering professional standards for such actions as we are pained by the lost of some of our close medical and healthcare professionals and colleagues that we personally know in countries like Italy, Spain, the United States and elsewhere. They are hundreds dying by the hour and millions soon too. Its time to stop being politically correct and even hypocritical and its time for people to start being vocal and proactive. People need to be told the truth and medical sites with the right information should not be stopped by threats or even being financially threatened by corporate entities that are being controlled by governments.
PLEASE HELP. URGENT APPEAL: Please help support our site and our initiatives to propel and aid research by making a donation to help sustain the site. Donations are accepted via paypal: https://www.thailandmedical.news/p/sponsorship
We at Thailand Medical News have always favoured stringent lockdowns, self-isolation, frequent testing as the main strategies to curtail the spread. Now with more studies emerging that social distancing really does not work, we strongly advocate that individuals and the public worldwide start taking legal actions and class suits against all sites, experts and authorities advocating social distancing of between 1 to 3 meters as these ignorant buffoons are actually endangering the lives of many.
A new research by qualified experts in their field from the MIT (Massachusetts Institute of Technology) lead by Dr Lydia Bourouiba, an Associate Professor at MIT, have researched the dynamics of exhalations (coughs and sneezes, for instance) for years at The Fluid Dynamics of Disease Transmission Laboratory and found exhalations cause gaseous clouds that can travel up to 27 feet (8.2 meters).
The new research is published in the Journal of The American Medical Association (JAMA). DOI: 10.1001/jama.2020.4756
The new research could have implications for the global Covid-19 pandemic, though measures called for by the Centers for Disease Control and Prevention and the World Health Organization call for six and three feet (0.9 m and 1.8 m) of space, respectively.(It should be noted that The WHO from day one has failed to prevent the global spread of the Covid-19 that originated from China plus they were the very same entity that advocated no border closures and no stopping of travel along with a lot of other misinformation that have resulted in the predicament that the world is in and yet no one has started any actions against any of these individuals while the US CDC is the hopeless entity that messed up on the diagnosing criteria and also on arranging of sufficient test kits that has resulted in the mess that the United Sates is in today yet no one from the entity has done the right thing of stepping down due to their incompetency. The American public and the world should never forget these two entities and the names and individuals associated.)
Dr Bourouiba told Thailand Medical News, "There's an urgency in revising the guidelines currently being given by the WHO and the CDC on the needs for social distancing and also protective equipment, particularly for the frontline health care workers.”
Dr Bourouiba's research calls for better measures to protect health care workers and, potentially, more distance from infected people who are coughing or sneezing. She said current guidelines are based on "large droplets" as the method of transmission for the virus and the idea that those large droplets can only go a certain distance.
In the research study, Bourouiba said peak exhalation speeds can reach 33 to 100 feet per second (36 km/h and 110 km/h) and "currently used surgical and N95 masks are not tested for these potential characteristics of respiratory emissions."
The dangerous idea being propagated by many that social distancing of between 1 to 3 meters based that droplets "hit a virtual wall and stop there and after that we are safe," is not based on evidence found in her research, Dr Bourouiba said, and also not based on "evidence that we have about COVID transmission."
Dr Bourouiba argued that a "gaseous cloud" that can carry droplets of all sizes is emitted when a person coughs, sneezes or otherwise exhales. The cloud is only partially mitigated by sneezing or coughing into your elbow.
She added, "In terms of the fluid regime on how the exhalations are emitted, the key point that we have shown is that there's a gaseous cloud that carries droplets of all sorts of sizes, not 'large' versus 'small' or 'droplets' versus 'aerosols.'"
Professor Dr Paul Pottinger, an infectious disease expert at the University of Washington School of Medicine, said questions remain about the distances at which the virus is effective.
He said, "For me, the question is not how far the germs can travel, but how far can they travel before they're no longer a threat. The smaller the germ particles, the lower the risk that they might infect somebody who would breathe them in or get them stuck in their nose or their mouth.”
He added, "The biggest threat we think with the coronavirus is actually the larger droplets. Droplets of saliva, snot, spit. Droplets that almost look like rain, if you will, when someone sneezes. Those droplets are large enough that gravity still acts on them. Usually, within about six feet of leaving somebody's body, those larger, more infectious droplets will drop to the ground. That's where the six-foot rule comes from. But it is the smaller and minute droplets that can be propelled by air and wind that is off a concern"
When questioned about this new study, the hopeless World Health Organisation (WHO) referred to a recent scientific brief on the methods of transmission, which recommended "droplet and contact precautions for those people caring for COVID-19 patients." The CDC did not respond to an emailed request for comment.
WHO however said later in a statement, "WHO carefully monitors emerging evidence about this critical topic and will update this scientific brief as more information becomes available. WHO welcomes modeling studies, which are helpful for planning purposes. WHO teams work with several modeling groups to inform our work."
As the SARS-Cov-2 coronavirus were effective at ranges of up to 27 feet (8.2 meters), as Bourouiba contends in her research, Dr Pottinger said he believes more people would be sick and more could have been affected as a result of the previous misinformation.
He added, "It takes a certain number of viral particles, we call them 'virions,' or individual viruses, it takes a certain number of individual viruses to actually get a foothold inside the body and cause that infection to get going.”
He further added, "Now, we don't know exactly what that number is, but it's probably more than a single virus. But we do know that this SARS-CoV-2 virus travels very efficiently by air.”
Dr Bourouiba said she wants to see recommendations made based on current science not "policies based on supply, for example, because we don't have enough PPE (personal protective equipment)." It's well-known PPE is in short supply nationwide and health care workers have been desperately trying to find effective ways to deal with shortages.
She added, "Although there remains a lot of questions to be addressed about how much virus is at a given distance or not, we have no answer one way or another at this time. Therefore, the precautionary principle should drive the policies to state that we should have high-grade respirators used for health care workers."
She stressed, "Once that's decided, that's the thrust that's needed to now mobilize most effectively the kind of tremendous high production level that is possible to reach in a great country like the United States. This thrust is not happening."
Please share this article to as many of your friends and loved ones to save their lives.
For the latest on strategies of Covid-19 prevention, keep logging on to; Thailand Medical News.
https://www.thailandmedical.news/news/breaking-news-covid-19-prevention-new-study-proves-that-social-distancing-of-1-to-3-meters-is-nothing-but-fake-news-and-misinformation
PS: We do not apologise for the name calling nor apologise for lowering professional standards for such actions as we are pained by the lost of some of our close medical and healthcare professionals and colleagues that we personally know in countries like Italy, Spain, the United States and elsewhere. They are hundreds dying by the hour and millions soon too. Its time to stop being politically correct and even hypocritical and its time for people to start being vocal and proactive. People need to be told the truth and medical sites with the right information should not be stopped by threats or even being financially threatened by corporate entities that are being controlled by governments.
PLEASE HELP. URGENT APPEAL: Please help support our site and our initiatives to propel and aid research by making a donation to help sustain the site. Donations are accepted via paypal: https://www.thailandmedical.news/p/sponsorship
___
The current coronavirus disease 2019 (COVID-19) outbreak vividly demonstrates the burden that respiratory infectious diseases impose in an intimately connected world. Unprecedented containment and mitigation policies have been implemented in an effort to limit the spread of COVID-19, including travel restrictions, screening and testing of travelers, isolation and quarantine, and school closures.
A key goal of such policies is to decrease the encounters between infected individuals and susceptible individuals and decelerate the rate of transmission. Although such social distancing strategies are critical in the current time of pandemic, it may seem surprising that the current understanding of the routes of host-to-host transmission in respiratory infectious diseases are predicated on a model of disease transmission developed in the 1930s that, by modern standards, seems overly simplified. Implementing public health recommendations based on these older models may limit the effectiveness of the proposed interventions.
Understanding Respiratory Infectious Disease Transmission
In 1897, Carl Flügge showed that pathogens were present in expiratory droplets large enough to settle around an infected individual. “Droplet transmission” by contact with the ejected and infected fluid phase of droplets was thought to be the primary route for respiratory transmission of diseases.
This view prevailed until William F. Wells focused on tuberculosis transmission in the 1930s and dichotomized respiratory droplet emissions into “large” and “small” droplets.
This view prevailed until William F. Wells focused on tuberculosis transmission in the 1930s and dichotomized respiratory droplet emissions into “large” and “small” droplets.
According to Wells, isolated droplets are emitted upon exhalation. Large droplets settle faster than they evaporate, contaminating the immediate vicinity of the infected individual. In contrast, small droplets evaporate faster than they settle. In this model, as small droplets transition from the warm and moist conditions of the respiratory system to the colder and drier outside environment, they evaporate and form residual particulates made of the dried material from the original droplets. These residual particulates are referred to as droplet nuclei or aerosols. These ideas resulted in a dichotomous classification between large vs small droplets, or droplets vs aerosol, which can then mediate transmission of respiratory disease. Infection control strategies were then developed based on whether a respiratory infectious disease is primarily transmitted via the large or the small droplet route.
The dichotomy of large vs small droplets remains at the core of the classification systems of routes of respiratory disease transmission adopted by the World Health Organization and other agencies, such as the Centers for Disease Control and Prevention. These classification systems employ various arbitrary droplet diameter cutoffs, from 5 to 10 μm, to categorize host-to-host transmission as droplets or aerosol routes.1 Such dichotomies continue to underly current risk management, major recommendations, and allocation of resources for response management associated with infection control, including for COVID-19. Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease.
New Model for Respiratory Emissions
Recent work has demonstrated that exhalations, sneezes, and coughs not only consist of mucosalivary droplets following short-range semiballistic emission trajectories but, importantly, are primarily made of a multiphase turbulent gas (a puff) cloud that entrains ambient air and traps and carries within it clusters of droplets with a continuum of droplet sizes (Figure; Video).2,3 The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets. Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes.
Respiratory Pathogen Emission Dynamics
This video demonstrates the phenomena in human sneezes visualized by light scattering toward the camera from multiple optical sources and at different distances. It illustrates how mucosalivary liquid emissions, in the form of droplets of a continuous size range, are coupled with the hot, moist, and high momentum gas cloud, which traps and carries them forward up to 7 to 8 m (26 ft).
This newer understanding of respiratory emission dynamics has implications for mask and respiratory design, social distancing recommendations, and other public health interventions during and after the COVID-19 pandemic. Click the related article link for complete details. Video courtesy of Lydia Bourouiba. Used with permission.
Owing to the forward momentum of the cloud, pathogen-bearing droplets are propelled much farther than if they were emitted in isolation without a turbulent puff cloud trapping and carrying them forward. Given various combinations of an individual patient’s physiology and environmental conditions, such as humidity and temperature, the gas cloud and its payload of pathogen-bearing droplets of all sizes can travel 23 to 27 feet (7-8 m).3,4 Importantly, the range of all droplets, large and small, is extended through their interaction with and trapping within the turbulent gas cloud, compared with the commonly accepted dichotomized droplet model that does not account for the possibility of a hot and moist gas cloud. Moreover, throughout the trajectory, droplets of all sizes settle out or evaporate at rates that depend not only on their size, but also on the degree of turbulence and speed of the gas cloud, coupled with the properties of the ambient environment (temperature, humidity, and airflow).
Droplets that settle along the trajectory can contaminate surfaces, while the rest remain trapped and clustered in the moving cloud. Eventually the cloud and its droplet payload lose momentum and coherence, and the remaining droplets within the cloud evaporate, producing residues or droplet nuclei that may stay suspended in the air for hours, following airflow patterns imposed by ventilation or climate-control systems. The evaporation of pathogen-laden droplets in complex biological fluids is poorly understood. The degree and rate of evaporation depend strongly on ambient temperature and humidity conditions, but also on the inner dynamics of the turbulent puff cloud coupled with the composition of the liquid exhaled by the patient.
A 2020 report from China demonstrated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus particles could be found in the ventilation systems in hospital rooms of patients with COVID-19.5 Finding virus particles in these systems is more consistent with the turbulent gas cloud hypothesis of disease transmission than the dichotomous model because it explains how viable virus particles can travel long distances from patients. Whether these data have clinical implications with respect to COVID-19 is unknown.
Although no studies have directly evaluated the biophysics of droplets and gas cloud formation for patients infected with the SARS-CoV-2 virus, several properties of the exhaled gas cloud and respiratory transmission may apply to this pathogen. If so, this possibility may influence current recommendations intended to minimize the risk for disease transmission. In the latest World Health Organization recommendations for COVID-19, health care personnel and other staff are advised to maintain a 3-foot (1-m)6 distance away from a person showing symptoms of disease, such as coughing and sneezing.
The Centers for Disease Control and Prevention recommends a 6-foot (2-m) separation.7,8
However, these distances are based on estimates of range that have not considered the possible presence of a high-momentum cloud carrying the droplets long distances.
Given the turbulent puff cloud dynamic model, recommendations for separations of 3 to 6 feet (1-2 m) may underestimate the distance, timescale, and persistence over which the cloud and its pathogenic payload travel, thus generating an underappreciated potential exposure range for a health care worker. For these and other reasons, wearing of appropriate personal protection equipment is vitally important for health care workers caring for patients who may be infected, even if they are farther than 6 feet away from a patient.
The Centers for Disease Control and Prevention recommends a 6-foot (2-m) separation.7,8
However, these distances are based on estimates of range that have not considered the possible presence of a high-momentum cloud carrying the droplets long distances.
Given the turbulent puff cloud dynamic model, recommendations for separations of 3 to 6 feet (1-2 m) may underestimate the distance, timescale, and persistence over which the cloud and its pathogenic payload travel, thus generating an underappreciated potential exposure range for a health care worker. For these and other reasons, wearing of appropriate personal protection equipment is vitally important for health care workers caring for patients who may be infected, even if they are farther than 6 feet away from a patient.
Turbulent gas cloud dynamics should influence the design and recommended use of surgical and other masks. These masks can be used both for source control (ie, reducing spread from an infected person) and for protection of the wearer (ie, preventing spread to an unaffected person). The protective efficacy of N95 masks depends on their ability to filter incoming air from aerosolized droplet nuclei. However, these masks are only designed for a certain range of environmental and local conditions and a limited duration of usage.9 Mask efficacy as source control depends on the ability of the mask to trap or alter the high-momentum gas cloud emission with its pathogenic payload. Peak exhalation speeds can reach up to 33 to 100 feet per second (10-30 m/s), creating a cloud that can span approximately 23 to 27 feet (7-8 m). Protective and source control masks, as well as other protective equipment, should have the ability to repeatedly withstand the kind of high-momentum multiphase turbulent gas cloud that may be ejected during a sneeze or a cough and the exposure from them. Currently used surgical and N95 masks are not tested for these potential characteristics of respiratory emissions.
There is a need to understand the biophysics of host-to-host respiratory disease transmission accounting for in-host physiology, pathogenesis, and epidemiological spread of disease. The rapid spread of COVID-19 highlights the need to better understand the dynamics of respiratory disease transmission by better characterizing transmission routes, the role of patient physiology in shaping them, and best approaches for source control to potentially improve protection of front-line workers and prevent disease from spreading to the most vulnerable members of the population.
https://jamanetwork.com/journals/jama/fullarticle/2763852
https://jamanetwork.com/journals/jama/fullarticle/2763852
Published Online: March 26, 2020. doi:10.1001/jama.2020.4756
Conflict of Interest Disclosures: None reported.
Funding/Support: Dr Bourouiba reported receiving research support from the Smith Family Foundation, the Massachusetts Institute of Technology (MIT) Policy Lab, the MIT Reed Fund, and the Esther and Harold E. Edgerton Career Development chair at MIT.
Role of the Funder/Sponsor: The funders had no role in the preparation, review or approval of the manuscript and decision to submit the manuscript for publication.
References
UVC Disinfection Lamp
VastaaPoista