May 15, 2020
Dear Governor Brown: We are a group of Oregon physicians and we urge you to require mandatory masking in indoor spaces where social distancing is not possible.
On masking, you require that employees mask when social distancing is not possible and your guidelines recommend that businesses require that their customers wear masks. Your guidelines should go further: all customers should mask in commercial spaces where social distancing is not possible.
BACKGROUND
Mechanisms of virus transmission
Asymptomatic transmission: We understand now that a person can be contagious and can spread COVID19 even when they have no symptoms. People are contagious before they exhibit symptoms of COVID19 or they are contagious with a case of COVID19 that never produces symptoms. Indeed, at any given time, half of the people spreading COVID19 have no symptoms. [https://science.sciencemag.org/content/368/6491/eabb6936]
“Airborne” transmission: Originally, it was believed that COVID19 spread through large droplets expelled by a contagious person via a cough or a sneeze. Large droplets travel less than 6 feet, hence the recommendation of staying 6 feet from others to prevent transmission of the virus. Recent evidence suggests that the virus can be transmitted via tiny droplets expelled by cough, sneeze, talking or singing and can travel beyond 6 feet. [https://www.medrxiv.org/content/10.1101/2020.04.02.20051177v1]
How Virus gains entry: The virus infects a well person via eyes, nose or mouth, either by direct entry (on droplets), or by having eyes, nose or mouth touched by a hand that has virus on it (hence the need for frequent handwashing).
Measures to decrease virus transmission
Social distancing of greater than 6 feet can decrease transmission of virus carried by large droplets.
Handwashing kills/removes virus from one’s hands and prevents transfer of virus to one’s eyes, nose, mouth.
Cleaning of surfaces kills/removes virus (expelled by a contagious person).
MASKS* (see below)
Testing/Tracing: A comprehensive system to identify cases of COVID19 through testing those who have symptoms as well as extensive background testing, tracing contacts of those who have COVID19, isolating those who have COVID19 and quantining those who have been exposed to someone with COVID19.
MASKS BLOCK TRANSMISSION OF COVID19
Masks block the virus-containing large and tiny droplets expelled by the mask wearing person who is speaking, singing, coughing or sneezing.
If any droplets do get out (from a masked or an unmasked person), a potential “recipient” of the virus blocks the droplets with their own mask.
Two masked people have very little chance of transmitting the virus between themselves.
Almost any mask material will block virus-containing droplets, but the tighter the weave of the material used and the more layers of material used, the fewer of the virus-containing droplets get through. (Medical grade masks should be reserved for medical providers.)
Masks should cover the nose and the mouth, the main sources and portals of virus-containing droplets.
Eyewear provides extra protection to block entry of virus-containing droplets.
Masks are cheap and/or easy to make. They can be a bandana or cloth napkin.
There are no side effects to wearing a mask.
SEVERAL REGIONS AND STATES REQUIRE MASKING IN THE US
Portions of 38 states require masks in indoor businesses and/or public transport.
West coast: Seattle/King County will require masks for those in indoor businesses and public transportation starting May 18. San Francisco, Los Angeles, San Diego require masks.
SPECIAL CONSIDERATIONS
There may be instances where an agency, a business, the county or the state will need to provide masks - for example, for our houseless population or for those who show up for public services and do not have a mask. Public transport agencies may need to provide masks.
Communities of Color
We are concerned that communities of color may experience an increase of enforcement of masking (as there have been reports of disproportionate enforcement of stay home orders) by law enforcement.
We are also concerned that individuals may be treated as if they are hiding their identities for reasons of a criminal nature.
Oregon must address some of these challenges through anti-bias education as well as surveillance of law enforcement and security guard activity. And in some situations, it may be impossible for individuals to feel or be safe due to threats of racially based violence.
For these reasons, any approach must rely on members from the community, who can speak to how to mitigate any potential negative impact while publicizing the benefits of masking to cut down on COVID19 transmission.
IN CONCLUSION
At this moment in our understanding of the transmission of COVID19, it is clear that the best way to protect yourself from contracting COVID19 is to stay at home. However, if you are out in public, masks are effective in dramatically reducing transmission. Given that masks are inexpensive and carry no medical risk factors, we strongly urge Governor Brown and the state of Oregon to require masking for all people older than two years old in indoor public settings.
Furthermore, the information for the public on OHA website and on Safe+Strong need to be updated to include masking as an important tool to decrease transmission. In particular, on the Safe+Strong website, a handout is titled “You can use a face covering if you….” This should read: “You should...” or (if you follow our advice) “You must…”
We are happy to discuss further with you.
Sincerely,
Lisa Reynolds, MD Pediatrician, Portland
(503) 550-1805
Sharon Meieran, MD, JD
Emergency Physician, Portland
Maxine Dexter, MD
Pulmonary and Critical Care, Portland
Smitha R. Chadaga, MD Internal Medicine, Hospitalist, Portland
Esther Choo, MD Emergency Medicine, Portland
Domi Le, MD Gastroenterology, Portland
(+135 physician signers)
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