COVID-19 | science, damage limitation, NO POLITICS

[Slobodan Blagojevic]

... If it can't be discussed in this thread, where can you discuss it?...

Alan, since the question you posed is political, it does not belong to this thread. You have your own Playpen thread for that.

[Alan Klein]

Here's some good news about "curve flattening" in British Columbia on Canada's west coast, https://www.cbc.ca/news/canada/british-columbia/bc-ontario-quebec-covid-19-1.5524056. It's an analysis of what went right. It was interesting to read about their public health planning. With all the shouting, we don't get to hear about how things can be done right, too boring I guess. Public health is really quite different than what we normally think of as medical care. The doctor-patient relationship is a one on one interaction but public health is a public commons arena, requires a different mind set.

Isn't BC less populated per square mile?  Wouldn't the bigger more crowded cities in Ontario and Quebec account for higher rates of infections?

[armand]

Dare I draw a different conclusion from what you said above? If one keeps the distance, masks are not needed?

No. First, this would travel faster and stay airborne longer without a mask, and second, the masks decrease your infectious spread around you.

The masks for everybody are not to prevent to wearer to get infected, but to decrease the chance that a wearer will infect others.

[Alan Klein]

Alan, since the question you posed is political, it does not belong to this thread. You have your own Playpen thread for that.

Oh, you're right. I got mixed up which thread I was posting on.  Sorry Jeremy.

[Robert Roaldi]

Dare I draw a different conclusion from what you said above? If one keeps the distance, masks are not needed?

Probably not a case of one or the other, maybe every little bit helps. Depending on specific conditions, some things may help more than others.

All I can discern from everything I've read is that masks may not help the wearer much in some cases, since eyes are still exposed and droplets may accumulate on the outside of masks that a person may later touch. You might need full face screens to provide passive protection of that kind.

Masks seem to protect others from people who are wearing masks. So if everyone wore them, that might be good. But it only matters in close quarters. When I'm out for a walk, I never get close enough to anyone for it to matter much, I wouldn't think. But that was true before Covid-19.

[Robert Roaldi]

Isn't BC less populated per square mile?  Wouldn't the bigger more crowded cities in Ontario and Quebec account for higher rates of infections?

B.C.'s demographics are probably not significantly different than anywhere else. The vast majority of people live in cities and towns, just like everywhere else. You might just have to drive farther to get to the next town, is all.

[LesPalenik]

Isn't BC less populated per square mile?  Wouldn't the bigger more crowded cities in Ontario and Quebec account for higher rates of infections?

All three provinces are quite large, but in all three of them most of the population resides just in a few cities in a relatively narrow strip in the southern regions. The population densities in Vancouver, Toronto and Montreal are about the same.
 

Montreal has emerged as Canada’s COVID-19 hot spot after an early spring break and close ties to New York and France sowed novel coronavirus infections that are rapidly growing into new cases and hospitalizations. Montreal, with about 5 per cent of Canada’s population, has about one-quarter of the country’s COVID-19 cases, according to the latest data published by public health authorities. The province of Quebec, with 22 per cent of Canada’s population, has about half of the country’s cases.

Public health officials and independent experts, along with Premier François Legault, point back to Feb. 28 to explain the province’s rapid expansion in coronavirus infection and serious illness. That was the last day of school before spring break for most Quebec school children.

As thousands of Quebeckers drove into the United States and flew to Europe and the Caribbean on holiday, the coronavirus was known mostly for infecting Asian countries, northern Italy, and a cruise ship off the coast of Japan. While Quebeckers were away, on March 1, Florida declared a public health emergency. New York followed on March 7, as Quebeckers started to head home.

https://www.theglobeandmail.com/canada/article-why-quebecs-coronavirus-cases-have-skyrocketed/

[Alan Klein]

B.C.'s demographics are probably not significantly different than anywhere else. The vast majority of people live in cities and towns, just like everywhere else. You might just have to drive farther to get to the next town, is all.

In the US, it's the population centers like NYC Metro Area that are getting hit hardest which makes a lot of sense.  If your neighbor is a bear, it's pretty hard to get infected.  Also, don't more foreigners go to Ontario and Quebec than BC cities.  So the exposure is greater. 

[Alan Klein]

In the US, it's the population centers like NYC Metro Area that are getting hit hardest which makes a lot of sense.  If your neighbor is a bear, it's pretty hard to get infected.  Also, don't more foreigners go to Ontario and Quebec than BC cities.  So the exposure is greater. 

Canada's Most Visited Cities
Montreal: 2,240,000 Visitors Per Year.
Vancouver: 3,900,000 Visitors Per Year.
Toronto: 4,520,000 Visitors Per Year.

[Alan Klein]

By comparison, NYC had about 60 million visitors last year which could account for it's high infection rate.

[LesPalenik]

Canada's Most Visited Cities
Montreal: 2,240,000 Visitors Per Year.
Vancouver: 3,900,000 Visitors Per Year.
Toronto: 4,520,000 Visitors Per Year.

This is actually an evidence that the city size or number of its visitors is not the most important factor. Montreal is smaller than Toronto, it had the fewest visitors out of the three cities, but the highest infection count. As pointed out in my previous post, the large infection count is attributed to many Quebec travelers who brought the virus back home from their vacation. 

[Alan Klein]

This is actually an evidence that the city size or number of its visitors is not the most important factor. Montreal is smaller than Toronto, it had the fewest visitors out of the three cities, but the highest infection count. As pointed out in my previous post, the large infection count is attributed to many Quebec travelers who brought the virus back home from their vacation. 

Well the French kiss more than the British. 

[Alan Goldhammer]

Dare I draw a different conclusion from what you said above? If one keeps the distance, masks are not needed?

Only if you are upwind.  I was thinking about this the other day in the grocery store which has central HVAC system for heating and cooling.  I think I was under one of the vents and felt the air coming in from the ceiling.  Viral particles if they are suspended in a somewhat dry environment can be blown around by the heating/cooling system.

[armand]

Only if you are upwind.  I was thinking about this the other day in the grocery store which has central HVAC system for heating and cooling.  I think I was under one of the vents and felt the air coming in from the ceiling.  Viral particles if they are suspended in a somewhat dry environment can be blown around by the heating/cooling system.

There was a discussion about how effective really are the HVAC filters, particularly when in an enclosed space, aka planes.

[chez]

Isn't BC less populated per square mile?  Wouldn't the bigger more crowded cities in Ontario and Quebec account for higher rates of infections?

Next to Manhatten, Vancouver's downtown has the 2nd highest density population in North America. There is also a huge Asia population in Vancouver and lots of people travel back and forth between Vancouver and Asia.

[chez]

Big difference between BC and Ontario / Quebec is BC started the isolation and distancing before spring break whereas the other provinces waited a bit, allowing the virus to spread within the cities. Just more proof that early acting really make a difference.

[RichDesmond]

If the government said today that they're taking away everyone's car and forcing people to take public transportation in order to save 30,000 lives annually due to auto accidents, most people would be furious, even those who  may have lost family members in accidents.  So asking them to give up their livelihood and let their families starve and calling them selfish just isn't fair and reasonable. Only the independently wealthy can be self-righteous and claim unselfishness.

About 90 people/day die in the US due to car accidents. CV-19 is killing over 1000/day right now, and that number is accelerating.
How big does it have to get before you'll support drastic action?

[Chris Kern]

There was a discussion about how effective really are the HVAC filters, particularly when in an enclosed space, aka planes.

As far as I am aware, no air-handler filters (at least, none sold for general commercial or residential use in the United States) are rated to trap particles smaller than 0.3 microns.  The COVID-19 virus is approximately 0.125 micron.  Of course, that's the virus itself.  My understanding is that as an infectious agent, the virus is almost always encapsulated in a droplet such as those emitted by a cough or sneeze.  I suspect those droplets typically are large enough to be captured by most of the filters that would be used in a commercial building, a home with forced-air ventilation, or an aircraft.  I read somewhere that the filters used in commercial airplanes have a rating similar to those used in hospital operating rooms.

As an aside, I've also read that about half the air circulated in airline cabins is fresh, the other half recirculated.  It's impractical to use 100 percent fresh air at the altitude most jets fly and provide an acceptable level of humidity for the cabin occupants.

[Manoli]

As an aside, I've also read that about half the air circulated in airline cabins is fresh, the other half recirculated.  It's impractical to use 100 percent fresh air at the altitude most jets fly and provide an acceptable level of humidity for the cabin occupants.

One of the essential 'ingredients' in airline air purification systems is, unless I'm mistaken, PG.

Propylene Glycol (PG) is a synthetic product that begins by oxidizing Propylene with organic hydrogen peroxide to create Propylene Oxide. From there, it is then hydrolysed into Propylene Glycol.

In 1942, a study(*) conducted by Dr. Oswald Hope Robertson of the University of Chicago’s Billings Hospital studied how the inhalation of propylene glycol impacted laboratory mice. Dr. Robertson was testing the effects of PG by inhalation. He suspected that this powerful ingredient could potentially be helpful for treating respiratory diseases, influenza, and even pneumonia.

He placed groups of mice into two chambers. In the first chamber, he sprayed the air with propylene glycol and then the flu virus. In the second chamber, he sprayed only the flu virus. All of the mice in the chamber sprayed with propylene glycol survived, whereas the mice exposed only to the flu virus died.

Dr. Robertson concluded, “The propylene glycol itself was a potent germicide. One part of glycol in 2,000,000 parts of air would – within a few seconds – kill concentrations of air-suspended pneumococci, streptococci, and other bacteria numbering millions to the cubic foot.”  The results were published in the US National Library of Medicine in the same year. 

(*) http://content.time.com/time/magazine/article/0,9171,932876,00.html

Food for thought ?

[LesPalenik]

One of the essential 'ingredients' in airline air purification systems is, unless I'm mistaken, PG.

Propylene Glycol (PG) is a synthetic product that begins by oxidizing Propylene with organic hydrogen peroxide to create Propylene Oxide. From there, it is then hydrolysed into Propylene Glycol.

Food for thought ?

It sounds very impressive. Were there any subsequent studies and are any doctors or hospitals using this method to kill the bacteria?