3/ Much focus on importance of a #multidisciplinary approach. A few interesting quotes:
"The evidence is clear that SARS-COV-2 is airborne, yet guidelines in many countries do not yet reflect this, thus hampering the ability to control the spread and endangering health workers."
4/ "No aerosol scientists or engineers who understand transmission of respiratory viruses and movement of aerosols are on the WHO committee, and their expertise is not sought, prompting calls from scientists for WHO to acknowledge airborne transmission..."
5/ "The lack of experts on respiratory transmissible infection or aerosol science at the table meant that much of 2020 was spent on promotion of hygiene theatre, actively discouraging mask use and a resulting low awareness among the general public of [masks and ventilaion] ..."
6/ "There are many different disciplines relevant to pandemic control, incl. the sub-specialities of clinical medicine, epidemiology, basic science, drug development, public health, occupational health & aerosol science, all of which are needed to [control] ... this pandemic ..."
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1/2 @DrLaPook on the importance of quality face coverings (i.e. N95s or even multiple mask layers), esp. as worrying COVID variants rise (via @linseymarr).
But wrt to multiple #mask layers; mask FIT and overall BREATHABILITY also critical, because ... cbs.com/shows/cbs_even…
2/2 ... If it's hard to breath through a #mask, it is too restrictive/thick. Air (& aerosol) will always escape mask. If air exits via gaps rather than THROUGH layer(s), mask is ineffective!
E.g. watch where/how aerosol escapes this poorly-fitting mask
3/2 (bonus) Since mask fit is so so important (even for N95s), there are various strategies to help improve air flow *through* the mask layers & improve fit. This preprint paper shows improvement in mask filtration efficiency by adding a mask brace/fitter.
Important new preprint from Lednicky et al. on #aerosol transmission of COVID
*Aerosol <0.25 - 10 μm collected in car driven by COVID-patient w/ mild symptoms
*Viable virus only detected in airborne particles in size range 0.25 – 0.5 μm
Paper shows: "the potential risk of SARS-CoV-2 transmission by minimally symptomatic persons in the closed space inside of a car (w/ closed windows & air conditioning running), & suggest that a substantial component of that risk is via aerosolized virus." medrxiv.org/content/10.110…
This 👇 earlier paper by the same Lednicky et al. (published Sept. 2020) showed viable (infectious) SARS-CoV-2 was present in aerosols within the hospital room of COVID-19 patients.
1/ Adding #ventilation helps reduce (but not remove!) aerosols & risk from COVID. One simple measure of ventilation is to keep #CO2 sufficiently low. Simple CO2 sensors can be <$150 and are easy to take with you.
2/ The idea is that indoor #CO2 comes primarily from people breathing out; but breathing also produces potentially infectious aerosols. So keeping #CO2 levels <800 ppm (or <600 ppm) means air is likely refreshed rapidly enough to keep aerosol risk low.
3/ There are lots of good resources & articles on improving #ventilation & for using #CO2 monitors for rough checks. This article by @B_resnick from months ago is worth a read as a broad overview on various topics related to air safety wrt COVID/aerosols. vox.com/science-and-he…
Myth 1: #Aerosols are droplets with a diameter < 5 μm
Myth 2: All particles > 5 μm fall within 1-2 m of the source
Myth 3: If it's short range, then it can't be airborne
Myth 4: If R0 isn't as large as for #measles, then it can't be airborne
3/ Dispelled myths:
Myth 5a: If it's #airborne then surgical #masks (or cloth face coverings) won't work
Myth 5b: The virus is only 100 nm (0.1 μm) in size so filters and masks won't work
Myth 6: Unless it grows in tissue culture, it's not infectious
1/ During July 2020 many worked quickly to scramble #COVID19 prep before the Fall classes. I helped model estimated COVID #aerosol risk as @UofDenver made plans. Not allowed then, but shared now in case it can prompt discussion for Winter prep.
2/ A key concern at the time (& still) was #music ensemble classroom activities, b/c it was obvious early on that #COVIDisAirborne and that #choir & wind instruments were likely to present high COVID #aerosol risk.
3/ Using my version of an aerosol #boxmodel, I calculated probability that #SARSCoV2 could infect after breathed out by someone in specific classrooms. With this I could easily investigate best prevention bang for buck. I.e. Rehearsal duration? Wait time b/n classes? Etc.