“Social Distancing” Kills

Last month I wrote about the damage the Center for Disease Control’s (CDC’s) mask and respirator guidelines were doing to public health. They have since adopted more reasonable guidelines, recommending that everyone wear a mask in public instead of the former insane statement that “For the general American public, there is no added health benefit to wear a respiratory protective device.” How many American lives did this cost? They still stop short of making the best recommendation, which is for everyone to wear an N95 respirator in public. The N95 respirator is so labeled because it is tested to ensure that it blocks 95% of pathogens, thereby protecting the wearer against infection. (Yes, I know they’re scarce and medical professionals need them most, but there are homemade alternatives which are almost as good.) See this study report.

The CDC continues to make unfounded, unscientific and dangerous recommendations. The subject of this article concerns social distancing. The CDC states “To practice social or physical distancing, stay at least 6 feet (2 meters) from other people.” The media and government officials make the harmful recommendation worse by using the term “practicing safe social distancing.” The implication is that if we remain 6 feet apart, we are unlikely to become infected.

But important research done by Dr. Lydia Bourouiba, Assistant Professor at MIT and researcher of Applied Mathematics, along with companion researchers, starting in 2014 and continuing through this year have revealed that “pathogen-bearing droplets from a sneeze can travel 23 to 27 feet propelled only by the person’s ballistic release of air.” And with indoor ventilation systems and outdoor wind currents, no practical limit can be stated beyond which it is safe to be from an infected person. Just today, Fox News contributor, Dr. Janette Nesheiwat stated that virus born clouds could remain viable for up to 2 hours. How many have become infected and died while keeping six feet or more from an infected person or unknowingly walking into a viral aerosol cloud? By its misleading social distancing guidelines, the CDC has blood on its hands by withholding the truth which would enable us to stay safer.

Supporting research

To my knowledge, there are no scientific studies which support the CDC assertion that the Chinese corona virus "spreads mainly among people who are in close contact (within about 6 feet) for a prolonged period." In fact, years of scientific research and a recent study in a Chinese hospital provide strong evidence to the contrary.

In 2014, Dr. Bourouiba, with the assistance of Dr. John Bush, Professor of Applied Mathematics at MIT, used fluid mechanics to quantify the physics of sneezes and coughs into still air. They learned some very useful things about the travel of emitted pathogens.

Quoting the researchers: “We think of the cloud [from a sneeze] as being turbulent, that is to say very disordered, vigorous motion. If characteristic speed in that cloud is larger than its settling speed, then it will be dominated more by that internal cloud motion than by its settling speed. The smaller drops go much farther than the large drops, because the cloud keeps them afloat. The science shows that these clouds, particularly under usual conditions of temperature and buoyancy, have a tendency to go higher in the room and get sucked into the ventilation system. ‘I could be in this end of the building and somebody could be in contact with my pathogens through the filtration and ventilation system without me actually meeting that person.’”

“That COVID-19 pathogens can leave a patient’s room was confirmed by a recent study in a hospital in Singapore. It was reported in JAMA Network that: “Swabs taken from the air exhaust outlets tested positive, suggesting that small virus-laden droplets may be displaced by airflows and deposited on equipment such as vents.”

Hospital administrators know this, which is why we hear of COVID-19 patients being placed in “negative pressure” rooms. Under negative pressure, all the pathogens which escape into the room are quickly evacuated and pass through a filtration and sterilization system before being evacuated into the atmosphere. It is the same principle by which bathroom exhaust fans work.

That ventilation systems move pathogen clouds is not unique to hospital rooms. In recent computer simulations done by researchers in Finland, it was demonstrated that pathogens propelled from a person coughing will quickly spread over multiple aisles in a grocery store. All it takes is moving air.

I stated above that no practical limit can be stated beyond which it is safe to be from an infected person. In reporting on the work of Drs. Bourouiba and others, Peter Dizikes | MIT News Office reported: “Indeed, the study finds, the smaller droplets that emerge in a cough or sneeze may travel five to 200 times further than they would if those droplets simply moved as groups of unconnected particles.”

Later in 2016, Dr. Bourouiba and others published the results of high speed camera measurements of actual sneezes. Using two high-speed cameras, the researchers recorded more than 100 sneezes from healthy human subjects and captured the fraction of a second during which fluid is expelled from the mouth and flung through the air. These experiments helped confirm the engineering analysis results produced in 2014, that pathogen-bearing droplets from a sneeze can travel 23 to 27 feet.

Then last month on March 26, Dr. Bourouiba reported on recent findings specifically about the current COVID-19 crisis. This work was published in the prestigious Journal of the American Medical Association (JAMA). Quoting from JAMA Insights:

“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.”

“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 cloud that entrains ambient air and traps and carries within it clusters of droplets with a continuum of droplet sizes. 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.”

“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.”

“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) 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. 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.”

Conclusion

It would be a lot more honest, helpful and less dangerous to the public they are commissioned to protect if the CDC would write:

Stay as far away from other people as possible. Virus clouds from sneezes and coughs can be immediately propelled up to 27 feet or farther. Even talking or singing can emit virus-laden aerosols. In addition to the initial propulsion of pathogens, there are many variables which make it impossible to recommend a safe distance. Air conditioning design, room size and how fast people are moving around and stirring the air inside an enclosed space will affect how far and fast virus-containing aerosols will travel. Wind speed and direction, humidity, how fast people are moving and other variables will affect how far and fast virus-containing aerosols will travel person-to-person outside. Self-quarantining and immediately sterilizing incoming items such as mail and groceries is the safest protocol.

This proposed guideline is actually supported by scientific research, clinical setting studies and common sense.