Masks vs superspreaders?
July 29, 2020 1:50 PM Subscribe
Have there been any COVID-19 superspreader events in which the source is known to have been wearing a (non-medical) mask?
I've been reading about superspreader events and how the virus in these cases is pretty clearly airborne (or at least aerosol-borne), rather than being spread solely by large droplets (or, obviously, surface contamination). In some of these cases people have been infected despite being 10+ metres away from the identified source.
My department has already implemented mandatory masking in any shared indoor space for the research labs that have resumed operations. I want to get a sense of how safe we are, and also whether I should raise a fuss about other (non-faculty-of-science) units on campus if it turns out they aren't requiring masks and instead think that the 2-metre distancing is going to be enough.
I am aware that absence of evidence is not evidence of absence.
I've been reading about superspreader events and how the virus in these cases is pretty clearly airborne (or at least aerosol-borne), rather than being spread solely by large droplets (or, obviously, surface contamination). In some of these cases people have been infected despite being 10+ metres away from the identified source.
My department has already implemented mandatory masking in any shared indoor space for the research labs that have resumed operations. I want to get a sense of how safe we are, and also whether I should raise a fuss about other (non-faculty-of-science) units on campus if it turns out they aren't requiring masks and instead think that the 2-metre distancing is going to be enough.
I am aware that absence of evidence is not evidence of absence.
Was also coming here to share that anecdote and the same conclusion. I follow this stuff fairly closely as an interested-hobbyist and we've also been following it closely as libraries re-open. The big thing about interior spaces is looking at how the air gets circulated and look towards optimizing that. I'm not sure anyone is saying "Two meters with no masks is safe" they're just saying it's rule-of-thumb safer to have unmasked people at a distance than close in (and worth noting what they're doing, where singing, coughing and sneezing will move virus further than just breathing normally.)
posted by jessamyn at 2:31 PM on July 29, 2020 [2 favorites]
posted by jessamyn at 2:31 PM on July 29, 2020 [2 favorites]
Sharing space indoors for extended periods of time is dangerous, even masked and distant. See the three masked teachers who shared a classroom- all got sick, one died.
posted by noloveforned at 3:38 PM on July 29, 2020 [10 favorites]
posted by noloveforned at 3:38 PM on July 29, 2020 [10 favorites]
In the classroom setting, presumably the teachers could have each gotten it from one of the students rather than from each other - were the students masked? I don't see that detail in the article.
posted by needs more cowbell at 4:59 PM on July 29, 2020 [1 favorite]
posted by needs more cowbell at 4:59 PM on July 29, 2020 [1 favorite]
needs more cowbell, it sounds like there were no students in the classroom, just the teachers.
posted by mskyle at 5:08 PM on July 29, 2020 [5 favorites]
"I think that's really the message or the concern that our staff has is we can't even keep our staff safe by themselves ... how are we going to keep 20 kids in a classroom safe? I just don't see how that's possible to do that," he said.(emphasis mine)
posted by mskyle at 5:08 PM on July 29, 2020 [5 favorites]
This story has more detail about the three teachers. They were teaching remotely, just the three of them in the classroom. They did drop off materials to their students.
posted by Stacey at 6:15 PM on July 29, 2020 [1 favorite]
posted by Stacey at 6:15 PM on July 29, 2020 [1 favorite]
Response by poster: Something does not compute about the teacher story. They wore masks while taking turns doing on-line teaching?
I would like to see some other examples.
posted by heatherlogan at 8:13 PM on July 29, 2020 [5 favorites]
I would like to see some other examples.
posted by heatherlogan at 8:13 PM on July 29, 2020 [5 favorites]
The 3 teachers story is tragic. They could have infected each other, but we don't know.
What we do know about this case:
The teacher that died was immunocompromised amongst other pre-existing conditions.
We don't know how well they wore masks (self-reported).
We don't know who else they came into contact with.
--
We do know:
Masked is much safer than unmasked. How much safer? Depends on many things, not least of which is how well a mask is worn, what airflow is like (e.g in labs, our hoods should be doing multiple entire room volume air exchanges per hour, if people facie into hoods, this should lower burden tremendously) , humidity, rate of expulsion, how infected source is etc. This is true for both droplet and smaller aerosolized/air-carried transmission. (non medical masks cut both down, but the former much more than the latter)
Re: your actual question. I don't think you'll get answers that will pertain to your specific situation. Without knowing all of the above variables, we can't give you an answer beyond "make sure you're as far away from a source as possible, and try to filter and exchange air at your mouth or away from it".
What would be useful is to affordably upgrade peoples non-medical masks to be more efficient at filtering both outgoing and incoming breath.
posted by lalochezia at 9:36 AM on July 30, 2020 [3 favorites]
What we do know about this case:
The teacher that died was immunocompromised amongst other pre-existing conditions.
We don't know how well they wore masks (self-reported).
We don't know who else they came into contact with.
--
We do know:
Masked is much safer than unmasked. How much safer? Depends on many things, not least of which is how well a mask is worn, what airflow is like (e.g in labs, our hoods should be doing multiple entire room volume air exchanges per hour, if people facie into hoods, this should lower burden tremendously) , humidity, rate of expulsion, how infected source is etc. This is true for both droplet and smaller aerosolized/air-carried transmission. (non medical masks cut both down, but the former much more than the latter)
Re: your actual question. I don't think you'll get answers that will pertain to your specific situation. Without knowing all of the above variables, we can't give you an answer beyond "make sure you're as far away from a source as possible, and try to filter and exchange air at your mouth or away from it".
What would be useful is to affordably upgrade peoples non-medical masks to be more efficient at filtering both outgoing and incoming breath.
posted by lalochezia at 9:36 AM on July 30, 2020 [3 favorites]
Response by poster: My actual question is, "Have there been any COVID-19 superspreader events in which the source is known to have been wearing a (non-medical) mask?"
posted by heatherlogan at 5:48 PM on July 30, 2020
posted by heatherlogan at 5:48 PM on July 30, 2020
Best answer: Here is a large spreadsheet of 2000 known superspreader events. However it doesn't indicate masked status of anyone including the source though it does cite all its sources. From this article which discusses ventilation ans a COVID concern, at some length.
posted by jessamyn at 8:59 AM on July 31, 2020 [3 favorites]
posted by jessamyn at 8:59 AM on July 31, 2020 [3 favorites]
« Older Anxious first-time renter and reporting apartment... | Great Culture to Screen Culture Newer »
This thread is closed to new comments.
On the other hand there was the case of the Missouri hairstylists where two symptomatic (!) hairstylists exposed 139 clients over the course of several days, and
posted by fingersandtoes at 2:03 PM on July 29, 2020 [8 favorites]