Read on Twitter
THREAD
https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread">--> For weeks, I& #39;ve been tracking the scientific debate about whether we need masks to prevent transmission of the virus causing #COVID19 and whether it is #airborne. If you& #39;re confused, you are not alone. Stick with me here. Let& #39;s clear the air. 1/15
On Saturday, the World Health Organization used CAPS to say, "FACT: #COVID19 is NOT airborne." Here is the tweet. But keep reading this thread, because the wording is tricky. https://twitter.com/WHO/status/1243972193169616898">https://twitter.com/WHO/statu...
As I wrote about 2 weeks ago, essentially, the word & #39;airborne& #39; means something traveling in the air. But public health officials rely on a cutoff that any tiny bit of mucus larger than 5 microns in diameter that you cough out is called a & #39;droplet& #39; 3/15 https://www.wired.com/story/they-say-coronavirus-isnt-airborne-but-its-definitely-borne-by-air/">https://www.wired.com/story/the...
Why that cutoff? The idea of separating large & #39;droplets& #39; from smaller & #39;aerosols& #39; dates back to the 1930s (!!!). William Wells and his team proposed that pathogens could spread by air. Later, they housed guinea pigs above tuberculosis patients in a hospital to prove this. 4/15
The guinea pigs got sick with tuberculosis. Yet there was pushback against the airborne theory of transmission. Some aerobiologists say this was a reaction to the widely debunked & #39;miasma theory& #39; in which poisonous vapors were said to be the culprit in the spread of illness 5/15
Fast forward to March 14, 1977, when a plane was grounded for 3 hours without ventilation. There was an ill person on board with flu symptoms. Within days 72% of the 54 people aboard got sick. Yet there& #39;s still debate about how & #39;airborne& #39; flu is. 6/15 https://www.ncbi.nlm.nih.gov/pubmed/463858 ">https://www.ncbi.nlm.nih.gov/pubmed/46...
At the time I wrote my story two weeks ago, there were already concerning reports. In a @JAMA_current study of hospital isolation rooms in Singapore, air vent blades in one patient’s room did test positive for #SARSCoV2 (the #COVID19 virus): https://jamanetwork.com/journals/jama/fullarticle/2762692">https://jamanetwork.com/journals/... 7/15
Another study, from Wuhan, found that the levels of #SARSCoV2 in most #COVID19 patients& #39; rooms were undetectable or low, but it did find the presence of the virus in aerosol form. It is still not peer-reviewed, so proceed with caution. 8/15 https://abs.twimg.com/emoji/v2/... draggable="false" alt="🛑" title="Stop sign" aria-label="Emoji: Stop sign"> https://www.biorxiv.org/content/10.1101/2020.03.08.982637v1">https://www.biorxiv.org/content/1...
More recently, Nebraska researchers including @Prof_Lowe detected #SARSCoV2 in air samples collected from patients rooms. Finding traces of virus isn& #39;t the same as proving they are infectious. Could just be genetic skeletons. But it is worth noting. 9/15 https://www.medrxiv.org/content/10.1101/2020.03.23.20039446v2">https://www.medrxiv.org/content/1...
OK, so we& #39;ve just listed some recent studies. But what might have caught your attention is this intriguing graph markup by @jperla. Look at the & #39;mask countries& #39; vs the & #39;no mask& #39; countries. 10/15:
A lot of folks have also heard about the case of a choir, reported here by @RichReadReports. Sixty people showed up for rehearsal, 45 have been diagnosed with #COVID19 or have symptoms, at least 3 have been hospitalized, and 2 are dead. 11/15 https://www.latimes.com/world-nation/story/2020-03-29/coronavirus-choir-outbreak">https://www.latimes.com/world-nat...
This is all concerning. And as @zeynep presciently wrote a couple weeks ago: "The top-down conversation around masks has become a case study in how not to communicate with the public." 12/15 https://www.nytimes.com/2020/03/17/opinion/coronavirus-face-masks.html">https://www.nytimes.com/2020/03/1...
Fast-forward to this week. @KnvulS& #39;s article aptly captures the changing tide: "More Americans Should Probably Wear Masks for Protection" -- the tone is starting to shift. 13/15 https://www.nytimes.com/2020/03/27/health/us-coronavirus-face-masks.html">https://www.nytimes.com/2020/03/2...
Public health experts distinguish between & #39;face masks& #39; such as surgical masks that are loosely fitting and & #39;respirators& #39; like N95s. Why are they called N95s? Because they filter out 95% of particles smaller than 0.3 microns if properly fitted. Here& #39;s the FDA& #39;s explanation 14/15
Wanna know what makes mask manufacturing so special? MELT-BLOWN FABRIC. Unfortunately, not something that you find at your local craft store. Here& #39;s a story by @EmilyZFeng and @Amy_23_Cheng @ 15/n https://www.npr.org/sections/goatsandsoda/2020/03/16/814929294/covid-19-has-caused-a-shortage-of-face-masks-but-theyre-surprisingly-hard-to-mak">https://www.npr.org/sections/...
If you& #39;d like to get your blood boiling, then read this story about how on Feb 5, HHS Secretary Azar requested $2 billion to buy supplies like respirator masks for the national stockpile. That request was cut 75% by the Trump administration: 16/n https://www.washingtonpost.com/national/health-science/desperate-for-medical-equipment-states-encounter-a-beleaguered-national-stockpile/2020/03/28/1f4f9a0a-6f82-11ea-aa80-c2470c6b2034_story.html">https://www.washingtonpost.com/national/...
What to do? @jeremyphoward "Yes, there is a shortage of manufactured masks, and these should go to hospital workers. But anyone can make a mask at home by cutting up a cotton T-shirt, tying it back together and then washing it at the end of the day." 17/n https://www.washingtonpost.com/outlook/2020/03/28/masks-all-coronavirus/">https://www.washingtonpost.com/outlook/2...
MIT prof Lydia Bourouiba says:
"Wearing of appropriate personal protection equipment is vitally important for health care workers caring for patients who may be infected, EVEN IF THEY ARE FARTHER THAN 6 FEET AWAY from a patient."
(CAPS MINE) 18/n https://jamanetwork.com/journals/jama/fullarticle/2763852">https://jamanetwork.com/journals/...
"Wearing of appropriate personal protection equipment is vitally important for health care workers caring for patients who may be infected, EVEN IF THEY ARE FARTHER THAN 6 FEET AWAY from a patient."
(CAPS MINE) 18/n https://jamanetwork.com/journals/jama/fullarticle/2763852">https://jamanetwork.com/journals/...
Would you rather see an explainer on #airborne transmission on @YouTube? Here is @MIT prof Lydia Bourouiba& #39;s @TEDMED talk on how diseases and epidemics move through a breath of air. 19/n https://www.tedmed.com/talks/show?id=730067">https://www.tedmed.com/talks/sho...
And here& #39;s Prof. Bourouiba on the @EPIDEMICpodcast (and me) talking about this & #39;false dichotomy& #39; between droplets and fine aerosols. https://podcasts.apple.com/us/podcast/bonus-false-dichotomy-airborne-versus-droplet-roxanne/id1499394284?i=1000469003736
And">https://podcasts.apple.com/us/podcas... here& #39;s me talking more about this on the recent #Resetpod 20/n https://podcasts.apple.com/us/podcast/airborne-explained/id1479107698?i=1000469843693">https://podcasts.apple.com/us/podcas...
And">https://podcasts.apple.com/us/podcas... here& #39;s me talking more about this on the recent #Resetpod 20/n https://podcasts.apple.com/us/podcast/airborne-explained/id1479107698?i=1000469843693">https://podcasts.apple.com/us/podcas...
Ughhh. I am really bad at making a #Thread. It& #39;s taken me 2 hours and I forgot the most important thing:
1. Health officials say #COVID19 not airborne because they say it is only spread by large & #39;droplets& #39;
2. But large droplets can travel farther under certain conditions 21/n
1. Health officials say #COVID19 not airborne because they say it is only spread by large & #39;droplets& #39;
2. But large droplets can travel farther under certain conditions 21/n
For example, aerobiologists point out that wind can carry large droplets far (think about the sea spray off of waves at the ocean on a windy day). They also say cough/sneeze droplets can sometimes go beyond 6 feet when taking into account the force of the & #39;cloud& #39; you exhale 22/n
Last tweet on this. @linseymarr has been 100% amazing at #scicomm on this subject. Follow her. Also, the GIF in the initial tweet is from Julian Tang in the journal @PLOSONE.
QED: We all need masks, but healthcare workers REALLY need proper masks.
23/n
QED: We all need masks, but healthcare workers REALLY need proper masks.
23/n
But wait... there& #39;s more!
@ferrisjabr has this incredible new story in @WIRED on why widespread mask wearing is an essential public health measure. He writes, "The collective evidence makes a strong case for universal mask wearing during a pandemic."
24/n https://www.wired.com/story/its-time-to-face-facts-america-masks-work/">https://www.wired.com/story/its...
@ferrisjabr has this incredible new story in @WIRED on why widespread mask wearing is an essential public health measure. He writes, "The collective evidence makes a strong case for universal mask wearing during a pandemic."
24/n https://www.wired.com/story/its-time-to-face-facts-america-masks-work/">https://www.wired.com/story/its...
CORRECTION: # 14 out of 15 in this thread should have read: "Because they filter out 95% of particles LARGER than 0.3 microns if properly fitted."
25/n
25/n
One more chilling study for this #Thread. Middle East Respiratory Syndrome is a cousin of #COVID19. In 2015, a 35-year old man exposed 1,600 people in an ER to MERS, infecting 82 folks: 33 patients, 8 staff + 41 visitors.
Here& #39;s the press release:
26/n https://www.sciencedaily.com/releases/2016/07/160710094054.htm">https://www.sciencedaily.com/releases/...
Here& #39;s the press release:
26/n https://www.sciencedaily.com/releases/2016/07/160710094054.htm">https://www.sciencedaily.com/releases/...
I’m mortified that I neglected to give a shout out to the awesome aerobiologist @Don_Milton in this thread. He rules! When asked about why the WHO resists the idea of airborne #COVID19 he says: “I think they are talking out of their hats.” 27/n https://www.npr.org/2020/03/28/823292062/who-reviews-available-evidence-on-coronavirus-transmission-through-air">https://www.npr.org/2020/03/2...
Well, I don& #39;t have a SoundCloud but I do have a gaseous cloud of droplets when I cough.
And I also send free email alerts for my news articles if you want to sign up for them: https://roxanne.substack.com/p/coming-soon ">https://roxanne.substack.com/p/coming-...
And I also send free email alerts for my news articles if you want to sign up for them: https://roxanne.substack.com/p/coming-soon ">https://roxanne.substack.com/p/coming-...
