RECOMMENDATION FROM the TETON DISTRICT HEALTH OFFICER
PERSONAL FACE MASK RECOMMENDATION FOR ALL PEOPLE WITHIN TETON COUNTY, WYOMING
RECOMMENDATION #7
All people in Teton County should wear cloth face coverings in public settings where other physical distancing measures may be difficult to maintain (e.g. grocery stores, pharmacies, crowded outdoor spaces such as sidewalks, and workplaces).
BACKGROUND and DETAIL SUPPORTING RECOMMENDATION
Teton District Health Officer Dr. Travis Riddell, following guidelines published by the U.S. Centers for Disease Control (CDC) on April 3, 2020, recommends that all people in Teton County, Wyoming wear cloth face coverings in public settings where other physical distancing measures may be difficult to maintain (e.g., grocery stores, pharmacies, crowded outdoor spaces such as sidewalks, and workplaces).
SARS-CoV-2, the virus that causes novel coronavirus disease (COVID-19), may be aerosolized "from normal breathing," according to a letter by a committee of the National Academies of Sciences, Engineering, and Medicine. The letter, sent to the White House Office of Science and Technology Policy on April 1, cites numerous studies indicating the presence of coronavirus in aerosols. In one, air samples collected more than 6 feet from two patients in COVID-19 isolation rooms tested positive for SARS-CoV-2 RNA.
In another study, patients with seasonal coronaviruses (other than SARS-CoV-2) were randomized to exhale breath with or without surgical face masks on. Viral RNA was detected in 40% of aerosols and 30% of respiratory droplets collected from participants without a face mask — but in none collected from those wearing a mask.
Dr. Riddell therefore advises the use of simple cloth face coverings to slow the spread of the virus and help people who may have the virus and do not know it from transmitting it to others. This is a cooperative, “I protect you; you protect me” approach.
Cloth face coverings fashioned from household items or made at home from common materials at low cost can be used as an additional, voluntary public health measure IN ADDITION to physical distancing requirements, state and local public health orders, and other recommendations which continue to be in place.
The CDC offers guidance on how to make and wear cloth masks on its website. Separately, a New York Times story examines the evidence on which materials might best filter out virus (e.g., pillowcases and flannel pajamas, among others). The Times quotes the following advice from Dr. Scott Segal, an anesthesiologist who has studied homemade masks: "Hold it up to a bright light. If light passes really easily through the fibers and you can almost see the fibers, it’s not a good fabric. If it’s a denser weave of thicker material and light doesn’t pass through it as much, that’s the material you want to use."
April 6, 2020
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Cloth face coverings should not be placed on young children under age 2, anyone who has trouble breathing, or is unconscious, incapacitated or otherwise unable to remove the mask without assistance.
The cloth face coverings recommended are not surgical masks or N-95 respirators. Those are critical supplies that must continue to be reserved for healthcare workers and other medical first responders, as recommended by current CDC guidance.
DEFINITIONS
For purposes of this Recommendation, the following are defined as follows:
Physical Distancing Requirements includes maintaining at least sixfoot distancing from other individuals, washing hands with soap and water for at least twenty seconds as frequently as possible or using hand sanitizer, covering coughs or sneezes (into the sleeve or elbow, not hands), regularly cleaning high touch surfaces and not shaking hands.
LINKS
National Academies’ letter (Registration required) Randomized trial of exhaled breath with & without face masks, in Nature Medicine (Free) CDC recommendation on cloth face coverings (Free) CDC’s "How to Wear a Cloth Face Covering" guidance (Free) New York Times story (Free)