NOTE: THIS IS NOT THE TYPE OF MASK YOU WANT
The following is a summary from The New England Journal of Medicine’s Journal Watch of the recommendation for wearing face coverings in public especially in
areas of significant community-based transmission.
April 5, 2020
SARS-CoV-2 May Be Transmissible Via “Normal Breathing”; Cloth Face Coverings Advised
By Amy Orciari Herman
Edited by Susan Sadoughi, MD, and André Sofair, MD, MPH
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, 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. The researchers with the latter study say the finding “has important implications for control of COVID-19.” THIS STUDY WAS DONE IN PATIENTS WITH SYMPTOMS.
Of note, the Academies’ letter cautions: “Studies that rely on [polymerase chain reaction] to detect the presence of viral RNA may not represent viable virus in sufficient amounts to produce infection. Nevertheless, the presence of viral RNA in air droplets and aerosols indicates the possibility of viral transmission via these routes.”
Days after the letter was sent, the CDC advised Americans over age 2 years to wear cloth face coverings (not surgical masks) “in public settings where other social distancing measures are difficult to maintain … especially in areas of significant community-based transmission.” The agency cited increasing evidence for asymptomatic SARS-CoV-2 transmission and specified that the face coverings are meant to “help [keep] people who may have the virus and do not know it from transmitting it to others.”
The CDC offers guidance on how to make and wear cloth masks on its website. The following advice is from Dr. Scott Segal, an anesthesiologist who’s 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.
These are the links to the CDC’s website. The first one has the recommendation. The second one shows how to make a facemask. If you are really bored there is the link to the Nature Medicine article on the droplets.
A TIGER GOT COVID-19, SO WHAT?
A tiger at the Bronx zoo got Covid-19 from their keeper. What are the implications for you and your pets? Remember in my blog post on self quarantine, I suggested isolating your self from others in your household including your pets because the risk of transmission to pets was unknown. This recent event reinforces the need for that recommendation. So if you are sick, stay away form other people and animals. Remember social distancing, especially if you are around tigers! 🙂