This morning’s New York Times roundup, by David Leonhart, mentioned a blog post by a Dartmouth biologist, Erin S. Bromage: The Risks – Know Them – Avoid Them.  It is an excellent explanation of the role of time, airflow, viral density in spread of disease. A little math, lots of science and some references to serious papers. It contains some very practical information: basically, avoid enclosed spaces where you might spend time with other people. Worth a read.

Here are some excerpts:

    Indoor spaces, with limited air exchange or recycled air and lots of people, are concerning from a transmission standpoint. We know that 60 people in a volleyball court-sized room (choir) results in massive infections. Same situation with the restaurant and the call center.  Social distancing guidelines don’t hold in indoor spaces where you spend a lot of time, as people on the opposite side of the room were infected.

The principle is viral exposure over an extended period of time. In all these cases, people were exposed to the virus in the air for a prolonged period (hours). Even if they were 50 feet away (choir or call center), even a low dose of the virus in the air reaching them, over a sustained period, was enough to cause infection and in some cases, death.

Social distancing rules are really to protect you with brief exposures or outdoor exposures. In these situations there is not enough time to achieve the infectious viral load when you are standing 6 feet apart or where wind and the infinite outdoor space for viral dilution reduces viral load.

… When assessing the risk of infection (via respiration) at the grocery store or mall, you need to consider the volume of the air space (very large), the number of people (restricted), how long people are spending in the store (workers – all day; customers – an hour). Taken together, for a person shopping: the low density, high air volume of the store, along with the restricted time you spend in the store, means that the opportunity to receive an infectious dose is low. But, for the store worker, the extended time they spend in the store provides a greater opportunity to receive the infectious dose and therefore the job becomes more risky.

… Basically, as the work closures are loosened, and we start to venture out more, possibly even resuming in-office activities, you need to look at your environment and make judgments. How many people are here, how much airflow is there around me, and how long will I be in this environment. If you are in an open floorplan office, you really need critically assess the risk (volume, people, and airflow). … If you are sitting in a well ventilated space, with few people, the risk is low.

…If I am outside, and I walk past someone, remember it is “dose and time” needed for infection. You would have to be in their airstream for 5+ minutes for a chance of infection.

Be careful out there.

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800,000 doctors are telling Donald Trump that his “plan” to reopen businesses by Easter is a bad idea. In a letter delivered to Trump on March 27, 2020, organizations representing American physicians in a vast range of specialties voiced their concerns about ending social distancing as COVID-19 continues to spread across the US and has killed at least 1,000 people.

The letter came in response to Trump’s publicly declared preference for ending social distancing and having the economy up and running by Easter, a date he chose because he sees it as  “a beautiful time,” and because, it has been reported, he has grown impatient with being cooped up in the White House and unable to hold the big campaign rallies that he thrives on.

“Federal, state and local governments should only set a date for lifting nationwide social distancing restrictions consistent with assessments by public health and medical experts,” the letter said. “Lifting restrictions sooner will gravely jeopardize the health of all Americans and extend the devastation of the COVID-10 pandemic.”

Here is the full text of the letter and the list of signers.

CMSS Statement on Restrictions to Slow the COVID-19 Pandemic

March 27, 2020

Dear President Trump, Vice President Pence, and Ambassador Birx:

Thank you for actively engaging the health care community—particularly the nation’s physicians and the organizations that represent them—in addressing the COVID-19 pandemic in the United States.

As more than 800,000 physicians across more than 40 specialties in medicine, we continue to support travel and gathering restrictions to slow the transmission of coronavirus disease 2019 (COVID-19). Physicians, other health professionals, and staff are putting themselves in harm’s way without adequate personal protective equipment or necessary tools (such as ventilators) as well as with no proven treatment or vaccine for the virus.

Significant COVID-19 transmission continues across the United States, and we need your leadership in supporting science-based recommendations on social distancing that can slow the virus. Our societies have closely adhered to these measures by moving our staff to fulltime telework and canceling in-person meetings (including annual meetings). These actions have helped to keep physicians and other health professionals in health care facilities, including hospitals, and reduce the risk of spreading COVID-19.

Statewide efforts alone will not sufficiently control this public health crisis. A strong nationwide plan that supports and enforces social distancing—and recognizes that our health and our economy are inextricably linked—should remain in place until public health and medical experts indicate it can be lifted.

Federal, state, and local governments should only set a date for lifting nationwide social distancing restrictions consistent with assessments by public health and medical experts. Lifting restrictions sooner will gravely jeopardize the health of all Americans and extend the devastation of the COVID-19 pandemic.

Again, thank you for actively engaging the nation’s physicians and the organizations that represent them. We appreciate your considering these comments and welcome an opportunity for further dialogue.

Sincerely,

Council of Medical Specialty Societies

American Academy of Allergy, Asthma & Immunology
American Academy of Dermatology
American Academy of Family Physicians
American Academy of Hospice and Palliative Medicine
American Academy of Neurology
American Academy of Ophthalmology
American Academy of Orthopaedic Surgeons
American Academy of Pediatrics
American Academy of Physical Medicine and Rehabilitation
American Association of Clinical Endocrinologists
American College of Cardiology
American College of Emergency Physicians
American College of Medical Genetics and Genomics
American College of Obstetricians and Gynecologists
American College of Occupational and Environmental Medicine
American College of Physicians
American College of Preventive Medicine
American College of Radiology
American College of Rheumatology
American College of Surgeons
American Epilepsy Society
American Gastroenterological Association
American Geriatrics Society
American Medical Informatics Association
American Psychiatric Association
American Society of Anesthesiologists
American Society for Clinical Pathology
American Society of Colon and Rectal Surgeons
American Society of Hematology
American Society of Nephrology
American Society for Radiation Oncology
American Society for Reproductive Medicine
American Thoracic Society
American Urological Association
Association for Clinical Oncology
Infectious Diseases Society of America
North American Spine Society
Society of Critical Care Medicine
Society of Gynecologic Oncology
Society of Hospital Medicine
Society of Interventional Radiology
Society of Nuclear Medicine and Molecular Imaging
Society of Thoracic Surgeons
Society for Vascular Surgery

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Whenever anything unexpected happens, there are unintended consequences. Such is the case with the coronavirus and its impact on American politics. Rallies are out, and for good reason. Whoever heard of a rally in which supporters had to comply with six-foot social distancing rules?

Debates without audiences are in. No more pandering to the audience; no more interruption of the natural exchange of ideas because some in the audience has to have their “Whoo” moment.

This is unintended good news for those among us who see ourselves as political introverts, or perhaps those who are not admitted political introverts, but prefer to keep their distance.

There are various terms used to describe introverts. One is “quiet.” Who thought that they would ever get to experience Bernie Sanders with the decibel knob turned down? (Well, I was wrong about that, based on the Sunday, March 15 debate with Joe Biden).

But with the “present normal” of politics, and not withstanding Bernie, we are less physically assaulted by sound waves.  More of his energy can go into putting together thoughtful sentences rather than edgy slogans.

This is an excellent time for all of us to consider how we wish to be approached by those running for office. The Coronavirus has put the plug on rallies. It will be interesting to see if politicians can scale down their intensity and connect with voters in a way that is so vitally needed in these difficult times.

This story is cross-posted on the Political Introverts website.

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