Антимасочное

[ny_quant]

A 3,000 word deep dive into the evidence behind student mask mandates

Many countries around the world - with vax rates, case rates, and mortality above and below the US - do not require masks on students. Why does the US?

My latest for @NYMag https://t.co/r2nYIHVPNj

— David Zweig (@davidzweig) August 20, 2021

Canadian mannequin study finds mask filtration efficiencies of:

Cloth: 10%
Blue disposable: 12%
Fitted KN95: 46%
Fitted R95: 60%
KN95 with 3mm gaps: 3%

Even modest ventilation (2 air changes per hour) outperforms best mask.https://t.co/2GqCW50oyC

— Phil Kerpen (@kerpen) August 22, 2021

Comments

[misha-b.livejournal.com]

2015 studies are not terribly relevant.

Surgical masks have significant effects on disease reduction according to a new and seemingly very serious study.
Cloth masks appear only marginally useful.
https://www.poverty-action.org/publication/impact-community-masking-covid-19-cluster-randomized-trial-bangladesh

[ny-quant.livejournal.com]

If you consider O(10%) effect significant than yes. Compared to vaccines that are factor of 10 - 100 significant this is nothing.

If they posed the right question - how do the masks help fully vaccinated people? - that answer would probably be not at all.

[misha-b.livejournal.com]

10% overall but they increased percentage of people wearying masks from about 10% to 40% -- by about 1/3. So for an individual the effect should be closer to 30%. It is not nearly as effective as good vaccines but nothing to sneeze on (pun intended).

> If they posed the right question - how do the masks help fully vaccinated people?

This is an important question but not necessarily _the_ right question. For example, in Bangladesh Pfizer/Moderna vaccines may not be available at all and Chinese vaccines do not seem to be good enough.