The problem with the six-foot separation/Science Advances

Will this science live on?

Remember when we were all standing six feet apart in lines thinking that doing so was going to help protect us from Covid-19?

Well, a team of physicists from the University of Massachusetts and engineers from Spain’s University of Cadiz are now out with a study that concludes the idea of “increasing physical separation appear(s) to have a limited impact on reducing aerosol transmission.”

Their data-based conclusion makes perfect sense when you think about it. But you’re unlikely to have read about it anywhere because, well, who cares now?

Worse yet, if this study tracks with some of the lessons learned during the Spanish flu pandemic of the early 1900s, what is reported here is likely to be forgotten by the time the next new pandemic arrives.

What these researchers found while studying the movement of particles in the stagnant air likely to be found in your neighborhood shop or store is that the vapors holding the microscopic SARS-CoV-2 virus stayed suspended in the air where exhaled.

Simply put, they concluded that if you were in line behind someone infected with Covid, and that person puffed a big load of virus into the air, it hung there in a cloud waiting to gas you when you stepped forward.

But here’s their more technical description from the peer-reviewed study published in Science Advances:

“We ask the question: Where do the aerosols released by an infectious individual in a waiting line end up? During the waiting phase, we assume that an infectious person continually releases (breathes) airborne particles around them which slowly diffuse into the surrounding air.

“After some time elapses, they walk to the next position in line. The resulting reorganization of individuals advects and diffuses the airborne particles. Except in very slow situations, (however), the diffusion may be considered subdominant, with the characteristic diffusion timescale much larger than the average waiting period.”

Worsening effects?

Given their research, there is even a case to be made that standing six feet apart could actually have increased the risks of being infected. Imagine two people infected with Covid standing in line in front of you at those helpful six-foot separation marks some businesses put on the floor.

As you move forward, your first step moves you into a cloud of SARS-CoV-2 virus left by the person in front of you, and with your second step, you could move into an even more virus-saturated cloud left by two infected people.

Thankfully, the researchers did find that something as simple as changing the temperature of the building around check-out stations by heating or cooling the air could alter this dynamic. But nobody was thinking about this sort of thing during the height of the pandemic because a lot of people weren’t thinking.

They were panicking, and panic is the enemy of reason. Reason is now beginning to enter the discussion in the form of studies like this, but whether the studies will be remembered, only time will tell.

The researchers reported the way to reduce “the risks” of standing in line is by raising temperatures above  32°C, about 90°F, or cooling them to below  22°C, near 71°F, around checkout lines.

The physics of this are pretty simple. Warm air rises, pulling the plume above people standing in line, and the cold air sinks, dropping the plume out of the breath zone.

There is no “normal” temperature for U.S. retail stores, but the federal Occupational Health and Safety Administration (OSHA) recommends 68 to 76°F. The lower part of that range would encourage plumes to sink if the body heat of salespeople and queuing customers didn’t serve to raise the air temperature around a checkout counter, a phenomenon the researchers specifically mentioned.

“Additional influences from human body thermal plumes were noticeable in the overhead regions of the walkers,” they wrote. The heat from these plumes increases as more people stand in line, given that near-100-degree human bodies function as little, moveable heaters.

This is why igloos can help keep people warm. They trap and hold human body heat.

So does stagnant air, but not for nearly as long. Thus the dynamics of people moving can create a lot of variables in a shop or store.

“Since the walking speed, ambient temperature, and the wait-walk, time-period ratio are all variables,” the scientists wrote, “the problem in itself presents a rich complexity in outcomes, which might account for some of the variability in infection patterns recorded in literature.

“The present work has addressed the specific effects of line kinematics and temperature in a simplified waiting line setting, assuming a poorly ventilated indoor space. Variations in ventilation, humidity, and airflow conditions can affect the fluid dynamics of the transport and have an influence on the risks of transmission.”

Killer air

Ah, ventilation.

The danger of poorly ventilated spaces was obvious from the start of the Covid pandemic. Only six months into it, researchers in China reported on the case of a recirculating, air-conditioning system spreading the virus and infecting people in the tightly enclosed space of a Guangzhou restaurant.

Other studies echoing that conclusion soon followed, but the U.S. Centers for Disease Control (CDC) and U.S. political leaders were slow to accept the need for better ventilation in American businesses.

More than a year into the pandemic, a team of doctors at the University of Minnesota’s Center for Infectious Disease Research and Policy (CIDRAP), observed that the CDC, along with the World Health Organization (WHO), had been “insisting for many months after SARS-CoV-2 emerged that the virus was transmitted only by large droplets or hand contact. Only fairly recently did those agencies finally recognize that inhalation of small infectious particles in the air (‘aerosols’) is a more important mode of transmission.”

Part of the problem there appears to have stemmed from high-tech photographs showing the spray of moisture that comes out of our mouths when we exhale. Such photographs helped up the pandemic panic and fuel the country’s subsequent culture skirmish over masking.

“A new method for visualizing breath that is exhaled while someone is speaking or singing could provide important new insights into how diseases such as Covid-19 spread and the effectiveness of face masks,” Phys.org reported in December 2020.

A whole bunch of scientists were at the time preoccupied with “respiratory droplets.” The experts were saying the coronavirus was mainly transmitted by large droplets coming from the mouths of those coughing, sneezing or even talking loudly.

 “COVID-19 is spread mainly through exposure to respiratory droplets that tend to drop within six feet, That’s why it’s important to stay at least six feet (about two arm lengths) away from people who don’t live with you,” U.S. Covid czar Dr. Anthony Fauci said. 

The home page of the New England Journal of Medicine’s Covid web page for months featured one of the droplet photos and pushed the idea the greatest danger was from the large droplets.

Fauci, meanwhile, pushed back against the idea that minuscule, aerolized bits of SARS-CoV-2 were the problem. CNBC reported his admission to the American Medical Association that there was “a degree of aerosolization. But I’m going to take a step back and make sure that we learn the facts before we start talking about it.”

And never mind that the risk of infection from aerolized particles that can be inhaled deep into the lungs, not to mention the need for ventilation to dilute these particles in the air, had been known since the time of the Spanish flu pandemic in the early 1900s.

Five years on from the height of the pandemic panic, Fauci’s statement can now be seen for what it was: spin not science. He was happy to talk about large droplets and masks to block them, but not about aerosols, probably because of the belief that the idea of Covid hanging in the air would scare people.

The reality, on the other hand, made aerosols as likely a problem as particles from the start. Or maybe Fauci was trying to deceive himself knowing that the human immune system is better equipped to protect against large particles than ultrafine particles that can be inhaled deep into the lungs.

One must remember that there was at the time a lot of political gamesmanship going on to try to make Americans believe the SARS-CoV-2 virus could be stopped in its tracks. That started with the lockdowns that didn’t work only to be followed by the great handwashing campaign, though the evidence to support the spread of the virus by hand was weak from the beginning.

Nonetheless, Fauci told PBS that “the most important thing…is to wash your hands as frequently as possible. I can tell you, Judy, I wash my hands 50 times a day.”

Fauci’s claim to washing his hands 50 times a day now seems a little hard to believe. This would require washing them about every 10 minutes during the average, eight-hour workday or every 15 minutes during a 12-hour workday, given that no one, at least no one with medical training, would be wasting time washing their hands at home when there’s no threat from the viruses carried by other people.

The media, however, was as panicked as the public and never questioned anything Fauci said. You’d have thought “Judy,” would at least have asked Fauci, “Really, you wash your hands 50 times a day.”

But, no. He was worshipped as if a god of science by a mainstream media that abandoned its responsibility to question everything. They didn’t.

As the years pass, it looks more and more like theu should have spent more time listening to Sweden’s Covid czar – Anders Tegnell – instead of attacking him for refusing to follow in lockstep the behaviors of the lockdown countries like the U.S.

Sweden did take a big hit early in the pandemic, primarily because of a failure to protect older Swedes living in senior care centers, but the country recovered quickly from that, possibly thanks to the lack of mental health issues later linked to lockdowns in the U.S. and elsewhere. 

Swedish life expectancy was back on track by 2021 and has continued to increase since.

Now at 83.62 years, it is in line with the steady rise that started from 71.2 years in 1950, according to Macrotrends data. The U.S. has not fared nearly so well; it only last year topped the pre-Covid life expectancy of 78.79 years in 2019, and is projected to reach only 79.4 this year, according to the same data source. 

Not only that, life-expectancy forecasters anticipate U.S. life expectancy falling farther and farther behind that of Sweden and the rest of Europe in the years to come due to bad diets and lazy lifestyles.

Bad messaging

But that’s neither here nor there. Other than serving as a reminder of how whacky the pandemic years, and how the most important messages about self-protection got lost in the noise.

Limiting the risk of infection was actually pretty simple:

1. Stay away from other people as much as possible, whether they masked or not
2. Stay out of poorly ventilated spaces where the virus could accumulate

A largely ignored study out of the University of Vermont underlined the first point. It found that “having more daily contact with adults and seniors” increased the likelihood of infection, and “further identified factors that have an increasing effect on the number of daily contacts, such as living in an apartment and wearing a mask.”

The study went almost wholly unreported by a mainstream media wanting to believe the government line that masks were protective and, at one point, the more of them the better.

“So if you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective,” Fauci told NBC’s Today Show in 2021. “That’s the reason why you see people either double masking or doing a version of an N95.”

There was then no evidence that double masking was any better than single masking, and little evidence that masking worked except, maybe, to buy people some extra time around already sick people before becoming infected themselves.

As for the danger of enclosed spaces, the CDC underlined the point in September 2020 when it reported that “adults with positive SARS-CoV-2 test results were approximately twice as likely to have reported dining at a restaurant than were those with negative SARS-CoV-2 test results….Reports of exposures in restaurants have been linked to air circulation.”

Or, more properly, due to the lack of air circulation, the problem that had previously done away with “smoking sections” in restaurants. They died because restaurant ventilation was so bed the smoke from the smoking section couldn’t be kept out of the non-smoking section or diluted enough so as to be negligible in the non-smoking section.

With the lack of ventilation still a problem, some communities, Anchorage among them, decided the solution was to simply order the closure of bars and restaurants, which only added more fuel to the culture skirmish that started with masking.

It would be two years into the pandemic before the CDC announced that “through the American Rescue Plan, Congress has appropriated nearly a half trillion dollars ($350 billion to state, local, and tribal governments and $122 billion to schools), roughly half of which remains available to support indoor air quality improvements in small businesses, industrial settings, commercial buildings, low-income housing, transportation hubs, and schools.”

But that’s really all kind of water under the bridge, too, because the most important message of the biggest pandemic since the Spanish flu still hasn’t reached the American masses, and that message was this:

Very few fit and healthy people died of Covid-19. The virus preyed on those whose health was already compromised. Some because they were unlucky. Many because they had for years ignored the need for daily physical activity to maintain physiological health.

And this health problem is bigger than just Covid. It touches on the country’s biggest killers – heart disease and cancer – many other health problems, not to mention quality of life, in the U.S.

But there is no government entity to sell the life-saving idea that “Exercise is Medicine.” There are no indications the words ever crossed the lips of Fauci, though there were phsyicians who recognized the value of exercise.

Dr. Robert Salis, the senior author on a research report that ended up being chosen as the American Journal of Preventive Medicine 2023 Article of the Year, was involved in an Eat Move Think podcast in May 2021 titled “The Best Way to Protect Against COVID-19” in which he advised that there is “an activity associated with reducing your risk of death from Covid by two and a half times, and cutting risk of developing severe Covid by two times. That activity is exercise.”

YouTube says it attracted “178 views.”

Surely it would have attracted more if Fauci had used his public grandstand to direct attention Salis’s way.