COVID-19: Is 6 feet really enough for social distancing? Physicians unclear about mask policies
Key Takeaways
As of Tuesday afternoon, the total number of confirmed COVID-19 cases has exceeded 800,000, with more than 40,000 deaths globally. In the United States, the number of cases has increased to more than 175,000 confirmed cases , with more than 3,400 deaths.
The death toll in the United States is not expected to peak until April 15th, with a projected total of 2,214 deaths per day. A total bed shortage of 54,046 and an ICU bed shortage of 13,856 is expected.
While many Americans are staying home and keeping their distance from others, new research has shown that we may not be standing far enough apart.
Virus cloud may be bigger than we think
Six feet has been the minimum safe distance recommended by many public health experts since the beginning of the COVID-19 pandemic, but the range of coughs and sneezes may be underestimated.
Lydia Bourouiba, PhD, associate professor, Massachusetts Institute of Technology (MIT) and an expert on the dynamics of exhalations, has found that exhalations can cause gaseous clouds that can travel up to 27 feet. Though she did not specifically study exhalations of patients with COVID-19, the new findings bring the 6-foot distancing guideline into question, and may have implications for future social distancing guidelines.
“There’s an urgency in revising the guidelines currently being given by the WHO and the CDC on the needs for protective equipment, particularly for the frontline health care workers,” Dr. Bourouiba said.
She added that current social distancing guidelines for the pandemic are based on transmission via “large droplets” that only go a short distance. Her recent article, published in JAMA, found that peak exhalation speeds under normal circumstances can reach 33 to 100 feet per second. What’s more, N95 masks, already in short supply, are not currently tested for such respiratory emission characteristics.
Paul Pottinger, MD, DTM&H, professor of infectious diseases, University of Washington School of Medicine, explained that while the cloud of exhalations may be wider spread, SARS-CoV-2 is not likely to be pathogenic from great distances.
“The biggest threat—we think—with the coronavirus is actually the larger droplets,” he explained, “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.”
Dr. Pottinger added that if the virus were effective at ranges of up to 27 feet, there would be many more infected individuals around the world.
Physicians face uncertain rules on mask policy in public areas
Tensions between some healthcare providers and hospital administrators appear to be growing regarding the practice of wearing surgical or N95 masks in public areas.
In Texas, an anesthesiologist was temporarily suspended without pay after wearing his respirator face mask in a hospital hallway. Henryk Nikicicz, MD, has asthma and hypertension, and he said the mask is vital in protecting his health. In Seattle, Oliver Small, MD, also an anesthesiologist, was fired for wearing a surgical mask while not involved in patient care, although the hospital has since changed its policy to allow masks in all patient areas.
A manager at The Cleveland Clinic sent an email to a group of doctors warning them not to “go rogue” and wear surgical masks around the hospital.
Some hospitals support the use of masks outside of treatment rooms, but others believe the masks are not necessary and do not allow it. Reasons for the bans vary, from cost-cutting measures to an unwillingness to cause panic among patients.
With COVID-19 putting a strain on many hospitals, the tensions have begun to boil over in some areas.
CDC mulling mask recommendations for general public
As of yet, there is no consensus on whether widespread use of facial coverings would help to prevent the spread of COVID-19, but the CDC is considering altering official guidance to encourage individuals to cover their faces while outside their homes.
The new guidance would not recommend that the general public wear surgical or N95 masks, but instead would address “do-it-yourself” cloth masks.
Former FDA commissioner Scott Gottlieb, MD, acknowledged that a covering such as a bandanna does not provide protection from contracting the virus, but it may limit the amount of respiratory droplets emitted by the mask wearer.
Critics are concerned that the makeshift masks may provide a false sense of security and lead to a decrease in effective social distancing. Another worry is that many people may not have enough information to properly clean masks between each use, which could also increase transmission.
Vaccine slated to start human trials by September
Johnson & Johnson recently announced that the company plans to begin human trials of its lead COVID-19 vaccination candidate by September, with batches potentially available for emergency use authorization by early 2021.
The company has partnered with Biomedical Advance Research and Development Authority (BARDA), a division of the Department of Health and Human Services.