Corona Virus #8

[shooterdon]

I feel as though this is only going to end with herd immunity at this point. We will need ~ 70% infection rate I believe I read for it to die out. Containment doesn't seem to be working, or should I say, people aren't following directives.

So much wrong with that graph...or am I missing something.

With two identical infection rates, if one country has 300MM people it will have more cases than a country with 50MM people.
If you do no, or minimal testing, you get fewer cases.

Case 1 One country with 300MM tests 5% of the population with an infection rate of 50%...number of cases is 7.5MM
Case 2 Another country with 50MM tests 5% of the population with an infection rate of 50%...number of cases is 1.25MM
Case 3 Another country with 50MM tests 2% of the pollution with an infection rate of 75%...number of case is .75MM

Which country is doing a better job of containment?

Numbers need to be normalized to mean anything. IE. cases per 100,000 tested would have some use.

 

[IslandTractor]

When someone goes on a ventilator, just what does that mean? Other than they can't breathe for themselves. I know they put a tube thru the nose into your lungs, and breathe for you. Does that mean you're unconscious? Either because you're in such bad shape or do they put you to sleep? Is someone there monitoring the machine constantly? What is the probability of recovering once you're on a ventilator? How long is someone normally on one before they are removed either by recovering or by not needing it anymore?

Assisted ventilation with a traditional mechanical ventilator is used either if a patient cannot breathe for themselves or if they cannot adequately oxygenate or remove carbon dioxide by breathing. One reason you cannot get enough oxygen is that the part of the lung where gas exchange occurs, the alveoli, can either be filled with fluid or collapsed. Both of these things happen in bad pneumonia. Once alveoli collapse, called atelectasis, it takes extra energy or work of breathing, to open again. The extra work of breathing tires the patient until they cannot keep up and that leads to respiratory failure so blood oxygen drops and carbon dioxide increases. Neither is good. Pneumonia patients usually CAN breathe for themselves but cannot get enough oxygen and so tire and breathing becomes less effective. Vicious circle. Also, using a simple mask to deliver oxygen doesn’t allow you to give maximum concentration of oxygen. Difficulty keeping up with the work of breathing and requiring more than about 40% oxygen are two reasons to intubate and mechanically ventilate a pneumonia patient.

A mechanical ventilator takes over the work of breathing (which means you have extra oxygen for other body functions) and also allows delivery of up to 100% oxygen. One other thing mechanical ventilators can do is provide higher pressures than normal breathing which can help in opening up collapsed alveoli. Finally, ventilators can control the pressure in the lung during exhaling so enough pressure remains to keep alveoli from collapsing.

CPAP and BiPAP can do some of what a mechanical ventilator can do for a pneumonia patient. The main thing they are typically used for is to maintain some back pressure during exhalation which keeps alveoli from collapsing. That can be very helpful and is all some patients need to maintain adequate oxygenation and ventilation by themselves. CPAP cannot take over breathing for you and doesn’t save you the work of breathing like a ventilator will. It’s also hard to get close to 100% oxygen delivery. Still, these devices have a role by freeing up ventilators for more seriously ill patients.

A lot is being done to make sure we don’t run out of ventilators but keep in mind that anybody who gets put on a mechanical ventilator for Covid19 has only about a 15% chance of survival.

 

[IslandTractor]

So much wrong with that graph...or am I missing something.

With two identical infection rates, if one country has 300MM people it will have more cases than a country with 50MM people.
If you do no, or minimal testing, you get fewer cases.

Case 1 One country with 300MM tests 5% of the population with an infection rate of 50%...number of cases is 7.5MM
Case 2 Another country with 50MM tests 5% of the population with an infection rate of 50%...number of cases is 1.25MM
Case 3 Another country with 50MM tests 2% of the pollution with an infection rate of 75%...number of case is .75MM

Which country is doing a better job of containment?

Numbers need to be normalized to mean anything. IE. cases per 100,000 tested would have some use.

Yes. Additionally countries and even regions in the same country have very different testing strategies. Italy apparently only tests if you come to a hospital sick. South Korea does drive by testing even of “worried well”. Some hospitals in NY are not even testing now and just using clinical criteria. Tough to make international comparisons.

 

[rswyan]

So much wrong with that graph...or am I missing something. ...

From the author of those graphs:

Here’s a video where I explain why we’re using log scales, showing absolute numbers instead of per capita, and much more:

Twitter

 

[dragoneggs]

Yesterday morning I was surprised to see live pictures of the MS ZAANDAM entering Fort Lauderdale, well this morning I was surprised to learn that my Aunt had not only been tested OK (as far as that can go) but then placed onto a chartered aircraft, flown out of the US and is now HOME! Yep, she still has to go through another 14 day quarantine, but not locked down in an internal cabin.

I briefly Skyped her as soon as my Sister told me she was home and asked her, "So, what did you bring me?!" :laughing:

Boy was that fast! They were talking about it being a couple day or so to get everyone off... the sick being first. Great news to hear she is home. Probably some stories to tell but being cooped up in an inner cabin, maybe not so much?

 

[RSR]

Twitter

View attachment 649109

View attachment 649108

There is something very interesting in these plots. That is, the two lowest countries, S. Korea and Japan (not shown on this plot but very similar to S. Korea) have something in common.

The populace wears masks.

As we start to understand more about the airborne spread, I think that is one way to slow things down, especially in urban areas. Of course, we'd need the masks to do that, but it is interesting, albeit late, to see the CDC start to come around to this idea. Of course, the WHO is still in denial.

 

[IslandTractor]

Good article explaining mechanical ventilator use in Covid-19:

Opinion | What You Should Know Before You Need a Ventilator - The New York Times

 

[Dftodd]

It seems to be working in rural areas, but the U.S. cities are having a hard time. I suppose when your neighbor is 10 ft. away it's hard to keep your distance.

I would think apartment buildings, and condos with shared entries, stairwells, and elevators would be a high risk place to be. No way to keep the separation required by social distancing. As well as the potential common areas touched, even inadvertantly.

Then the public transportation.

 

[shooterdon]

From the author of those graphs:


Twitter

Thank you the link.

His rationale for not (normalizing) using per 100,000 does not make sense unless you want to make small countries look better than others...or countries that do little testing to look better. He wants to dramatize the numbers...typical tactic to encourage fear mongering to sway and fool the more ignorant.

IT's comments are also germane.

It is easy to fool people with numbers that appear "fair". It is one reason we are so screwed up in dealing with this outbreak...ignorance, agendas, confusion, lack of accepted reporting protocols, etc.

I will continue to monitor deaths as the most reasonable measure of how bad things are and our status. I am fairly certain the number of deaths are being exaggerated to increase funding, resources, and fuel the panic (except those in China which are likely much higher). So, in a world that suffers 56,000,000 dead a year 65,000 Covit-19 deaths are not much. And in the US, with 2,800,000 deaths a year, our current toll of 8,200 is tragic but not significant.

I hope we continue to do everything reasonably possible to save lives and still maintain our perspective. We cannot factor in the number of deaths caused by focusing on this virus while others wait for treatment. Tying up a ventilator with a patient that has a 10% chance of survival would be criminal if a patient with a 50% chance is denied...Italy is an example.

Coronavirus pandemic jobs: US health care workers furloughed, laid off

Unintended consequences.

 

[RandyT]

When someone goes on a ventilator, just what does that mean? Other than they can't breathe for themselves. I know they put a tube thru the nose into your lungs, and breathe for you. Does that mean you're unconscious? Either because you're in such bad shape or do they put you to sleep? Is someone there monitoring the machine constantly? What is the probability of recovering once you're on a ventilator? How long is someone normally on one before they are removed either by recovering or by not needing it anymore?

It means your lungs can't provide enough O2 to your tissues to survive and must be supplemented by artificial means, eg, the ventilator. Short term patients are intubated, meaning a tube is inserted in their throat to provide an open pathway. Most patients are not unconscious, but are given sedatives and a paralyzing drug to keep them from fighting the vent. It is very uncomfortable to have a tube in your throat and the natural reaction is to get it out NOW. Once certain perimeters are met, staff will attempt to 'wean' the patient off the vent by removing it for short times to see if the patient can breathe on their own and maintain minimum O2 stats. The machine is generally used in ICU so staff is always nearby to monitor the machine. It can and will keep breathing for you even if you die, because the machine doesn't know you are dead. It pumps air or a mixture of O2/air. Time on the vent is dictated by your ability to recover. Some paralyzed accident victims are on the vent forever. Long term patients are trached for a more comfortable tube placement but that is a surgical procedure.

I am hearing 10-21 days for the people that actually survive. Which I am also hearing about 80% don't