Comments on: COVID-19 Doesn’t Play

By: Mel Tillis

Mel Tillis — Sat, 12 Dec 2020 14:30:30 +0000

My wife and I tested positive the day before Thanksgiving and we’re not sure where we were infected either. Our daughter tested negative. We’ve taken a cautiously vigilant approach since the beginning; wearing masks, distancing, and choosing destinations wisely. We suspect the infection may have come from either her workplace or her doctor’s office. I also suspect that surface contact spread may be a bigger issue than experts think at this time. My unsubstantiated, and possibly ignorant, theory is that workers who touch their masks frequently at retail establishments may be another source of superspread

Anyway, thanks for the information you share and take care.

By: Richard Willmer

Richard Willmer — Fri, 11 Dec 2020 10:39:51 +0000

In reply to Erp.

Good on you for your high standards.

Nothing “unfortunate” about protecting others. If we all did that, then we’d all be protected!

By: DoctorDJ

DoctorDJ — Mon, 07 Dec 2020 23:13:10 +0000

In reply to DoctorDJ.

MIT has modeled the transmission of covid indoors. https://indoor-covid-safety.herokuapp.com/

Let’s run this model for a small office (200 sq ft), 8 ft ceiling, mechanical ventilation, residential air filtration, 60% rel

humidity. Four folks in the room, in normal health, resting and talking. One is infectious with covid.

If no one wears a mask, the room air will be unsafe and infection transmission occur in 31 minutes.
If everyone wears a single layer cotton mask, the room air will be unsafe and infection transmission occurin 2 hours.
If everyone wears a multi-layer cotton mask, the room air will be unsafe in 3 hours.
If everyone wears a disposable surgical mask, the room air will be unsafe in 17 hours.
If everyone wears an N-95 mask, the room air will be unsafe in 4 days.

Hence, masks reduce (but don’t eliminate) the transmission risk.
This addresses the “masks are mandated, but infection still occurs; hence masks don’t work” argument.

By: DoctorDJ

DoctorDJ — Mon, 07 Dec 2020 11:46:36 +0000

“So are any of us safe indoors during the COVID-19 era? Can we go to a grocery store? Can we meet with a loved one? John Bush, a professor of applied mathematics, alongside his MIT colleague Martin Z. Bazant, have answered that question with a complex mathematical model, which simulates the fluid dynamics of virus-loaded respiratory droplets in any space, from a cozy kitchen to a gigantic concert hall.

The tool assumes one person in a room with you has COVID-19. Then, it hands you an incredible amount of control to tweak the variables at play. These variables include details about the building: What’s the square footage? What’s the height of the ceiling? How about the HVAC system—is it a standard domestic furnace or does it have a fancy HEPA filter? What’s the humidity? Is a window open? The variables also include all sorts of details about human behavior: How many other people are there with you? Are they wearing masks? Cotton or surgical? Do they wear masks properly or pull them down their face a bit? Are they whispering or singing?

At first glance, all of these controls might seem overwhelming. (And they are!) But the payoff is worth it. Because the tool gives you a very clear answer of how long how many people can safely be in a space together.”

https://www.fastcompany.com/90580290/one-person-in-the-room-with-you-has-covid-19-heres-how-long-it-takes-to-get-infected

By: MaryKaye

MaryKaye — Sun, 06 Dec 2020 21:30:50 +0000

Thank goodness you are okay. Please take good care of yourself–COVID has a nasty habit of roaring back just when you think it’s done.