Coronavirus

[Investor20]

Couple things about antibodies.

 

The antibody testing needs to be delineated between IgM and IgG to get a sense of timing and prevalence. (my assumption is that is what was being tested as that's what was commonly being tested across the country) Both become detectable and and wane at different time periods. Over time "months" nearly all who were infected will have their antibodies wane down to not detectible. Many getting tested in August could have "had antibodies" in March, April, May etc but show up negative in August. FWIW earlier readings have the likelihood as being most accurate as the start date for large scale exposure and initial community spread (and thus catching the start of the antibody curve if you will) is much closer to March then now. I haven't looked through the data being discussed but if a representative population was ~62% positive in early March that is a much more accurate level then what you would get now IMO. Consider that a floor, if again representative. Also clearly explains NYC infection curve (very low level of cases for months and months) AND their over representative death count and spike in spring.

 

Losing antibodies as delineated above is not uncommon and does not immediately point to reinfection or possibility. Look at worldwide re infection examples. Handful out of millions of cases. T cell immunity is what you guys are missing here. All the info you guys are looking for in NYC is in T cell immunity. The problem is there is no way do detect/test for such at this time.

 

I attached a graph giving a rough idea of what I am trying to convey. As it says chart for illustrative purposes only.

 

Agree there is clear waning of antibodies in not only NYC data but observed many places elsewhere.  I am reading the 20% present new york antibody as simply last several months of  infections, not cumulative infections from February.  My understanding of T Cell immunity is it does not stop infection but reduces severity of infection.  With this regard vaccines might not prevent re-infection, but only severity of infection:

 

“if everyone gets vaccinated and we continue to implement the public-health measures that I have been talking about incessantly over the last several months,”  Fauci said according to below article

https://www.self.com/story/fauci-masks-after-vaccine

[clutch]

I don't know why some people want it to be bad or get worse.

 

Obviously, so that they can keep blaming Trump...  ::)

[Investor20]

Emergency Department Visits Percentage of Visits for COVID-19-Like Illness (CLI)

https://www.cdc.gov/coronavirus/2019-ncov/covid-data/covidview/10022020/covid-like-illness.html

 

Week        Percent of Emergency Room Visit

202039 (Sep)              1.9

202006 (Feb)           2.2

 

US is already below February in percent Emergency room visits for Covid 19 like illness

 

 

 

[KCLarkin]

There's a big misconception about what the herd immunity threshold even is. For many, it seems to mean the point at which 1) the virus disappears or 2) that the virus no longer spreads. But that's not possible given the thousands of different respiratory viruses that circulate normally. Rather, the herd immunity threshold is better described as the point in which the virus crosses over from epidemic to endemic. Under that definition, HIT being reached and Rt>1 is not incompatible. The virus will still be around long after the epidemic has ended.

 

The literal definition of HIT is Rt<1.

 

P.s. To the MAGA-trolls, not everything is an attack on Trump. Do you have a secret agreement that if His name isn't mentioned at least once per page, you need to invoke His name?

[muscleman]

That's what I kept saying for a long time. We already have herd immunity in NYC and a few other places.

 

Yes, you've been wrong about this for a long time.

 

I know you've sorta apologized for this. But you predicted 20k daily cases by the end of August. It is October and the U.S. is still over 40k cases. Cases are up since your mea culpa.

 

Now you are using NYC as proof of herd immunity when they just partially re-opened indoor dining? And already have early signs of a second wave?

 

That's funny because i kept saying GA is the key test bed for my herd immunity hypothesis and based on infection cases/population, NYC should have reached herd immunity a long time ago.

But it doesn't matter. It doesn't fit your propoganda.

 

[Peregrine]

There's a big misconception about what the herd immunity threshold even is. For many, it seems to mean the point at which 1) the virus disappears or 2) that the virus no longer spreads. But that's not possible given the thousands of different respiratory viruses that circulate normally. Rather, the herd immunity threshold is better described as the point in which the virus crosses over from epidemic to endemic. Under that definition, HIT being reached and Rt>1 is not incompatible. The virus will still be around long after the epidemic has ended.

 

The literal definition of HIT is Rt<1.

 

 

No it isn't. Rt for the seasonal flu can be above 1 during the winter but do we still call that an epidemic? For Rt to be perpetually below 1 would mean the elimination of the disease, for which is not possible. I don't think you understand the implications of this math all that well.

[Liberty]

https://www.bbc.com/news/health-54296223

 

"'Long Covid': Why are some people not recovering?"

[LC]

I don't think you understand the implications of this math all that well.

 

Oh, this is ironic.

[Peregrine]

I don't think you understand the implications of this math all that well.

 

Oh, this is ironic.

 

If Rt is perpetually below 1, that means perpetual decline in the number of infections with the end state being 0. This has never happened with respiratory viruses. The Spanish flu (H1N1) still circulates today as do the thousands of other coronaviruses and influenza.

[KCLarkin]

That's funny because i kept saying GA is the key test bed for my herd immunity hypothesis and based on infection cases/population, NYC should have reached herd immunity a long time ago.

But it doesn't matter. It doesn't fit your propoganda.

 

Georgia: Schools closed in Atlanta. Mask mandates. State of emergency. Gathering limits. Stay in place orders for LTC. Nice weather.

 

But MM has a hypothesis...

 

 

[KCLarkin]

For Rt to be perpetually below 1 would mean the elimination of the disease, for which is not possible. I don't think you understand the implications of this math all that well.

 

Hmm. It's almost like the "immunity" in herd immunity means something...

 

Rt for the seasonal flu can be above 1 during the winter but do we still call that an epidemic?

 

Yes, we do call that an epidemic. We have seasonal flu epidemics every single year.

[Peregrine]

For Rt to be perpetually below 1 would mean the elimination of the disease, for which is not possible. I don't think you understand the implications of this math all that well.

 

Hmm. It's almost like the "immunity" in herd immunity means something...

 

Exactly. Which is why the herd immunity term in the general lexicon has become a complete misnomer. This virus will be around long after a vaccine is widely available but at some point (and a lot sooner than many think), it will no longer be an epidemic. Instead, it will become endemic in the population just like all the other respiratory viruses that circulate regularly. This is how previous pandemics ended - viral infections were never eliminated.

[clutch]

P.s. To the MAGA-trolls, not everything is an attack on Trump. Do you have a secret agreement that if His name isn't mentioned at least once per page, you need to invoke His name?

 

Can you state one thing he did well regarding COVID without vomiting?

 

p.s. Yes, I'm trolling so you don't have to asnwer. ;D  Sorry, I'm having too much fun at this!

[Peregrine]

 

Rt for the seasonal flu can be above 1 during the winter but do we still call that an epidemic?

 

Yes, we do call that an epidemic. We have seasonal flu epidemics every single year.

 

CDC defines the threshold for an epidemic as 7.2% of total deaths, so no we don't get flu epidemics every year. But yes, some years the flu can get quite bad.

[Investor20]

For Rt to be perpetually below 1 would mean the elimination of the disease, for which is not possible. I don't think you understand the implications of this math all that well.

 

Hmm. It's almost like the "immunity" in herd immunity means something...

 

Exactly. Which is why the herd immunity term in the general lexicon has become a complete misnomer. This virus will be around long after a vaccine is widely available but at some point (and a lot sooner than many think), it will no longer be an epidemic. Instead, it will become endemic in the population just like all the other respiratory viruses that circulate regularly. This is how previous pandemics ended - viral infections were never eliminated.

 

Exactly Frank.  Infact as per CDC, the emergency visits for Covid like symptoms (CLI) to hospital are already at about February level (my earlier post). 

The hospitalizations are about at middle of March. Yes we can count Covid positives.  But ultimately its the hospitalizations that matter.

 

[orthopa]

For Rt to be perpetually below 1 would mean the elimination of the disease, for which is not possible. I don't think you understand the implications of this math all that well.

 

Hmm. It's almost like the "immunity" in herd immunity means something...

 

Exactly. Which is why the herd immunity term in the general lexicon has become a complete misnomer. This virus will be around long after a vaccine is widely available but at some point (and a lot sooner than many think), it will no longer be an epidemic. Instead, it will become endemic in the population just like all the other respiratory viruses that circulate regularly. This is how previous pandemics ended - viral infections were never eliminated.

 

Exactly Frank.  Infact as per CDC, the emergency visits for Covid like symptoms (CLI) to hospital are already at about February level (my earlier post). 

The hospitalizations are about at middle of March. Yes we can count Covid positives.  But ultimately its the hospitalizations that matter.

 

 

I think this is certainly where things have gotten out of hand. We used to worry about the hospitals being over run and mass deaths as a result. Now have per KCLarkins post a state of emergency, gathering limits, etc with daily deaths less then 20 day in the state of Georgia. That isn't rational on any measure.

[Gregmal]

Remember how unsafe it would be for professional athletes to play sports? Contact ones at that? And despite some leagues having little to no issues(NHL), and others having some big ones(NCAA, MLB), here we are. Cam Newton possibly coming back in less than a week. Same as DJT. Awful lot like the flu.

 

 

With all due respect to the ones here have actually made an effort to be unbiased and are just genuinely interested in the science, I think as it relates to markets and investing, provided nothing extraordinary such as a horrific mutation or a liberal takeover and grand shutdown of the US occurs again, covid is pretty much a non material market story and really just fodder for the science nerds and academics at this point. Anyone ever remotely in favor a shutdown should look at how FL, AZ, TX, GA breezed through their "crisis waves", without doing what Murphy or Cuomo did here in the Northeast.

 

The places in the market where it is material are places where psychological damage resulting from negligent shutdowns and politically charged and amped up news flow have created demand impairments. Which will linger a bit in the obvious areas but that too should have the worst behind it.

[muscleman]

Remember how unsafe it would be for professional athletes to play sports? Contact ones at that? And despite some leagues having little to no issues(NHL), and others having some big ones(NCAA, MLB), here we are. Cam Newton possibly coming back in less than a week. Same as DJT. Awful lot like the flu.

 

 

With all due respect to the ones here have actually made an effort to be unbiased and are just genuinely interested in the science, I think as it relates to markets and investing, provided nothing extraordinary such as a horrific mutation or a liberal takeover and grand shutdown of the US occurs again, covid is pretty much a non material market story and really just fodder for the science nerds and academics at this point. Anyone ever remotely in favor a shutdown should look at how FL, AZ, TX, GA breezed through their "crisis waves", without doing what Murphy or Cuomo did here in the Northeast.

 

The places in the market where it is material are places where psychological damage resulting from negligent shutdowns and politically charged and amped up news flow have created demand impairments. Which will linger a bit in the obvious areas but that too should have the worst behind it.

 

Back in August, Trump haters were laughing at GA's "chaotic school reopening" where few wear masks, and predicted that it would not end up well.

Today they say GA is doing well because they wear masks and have schools closed.

:) :) :) :) :) :) :)

[Cigarbutt]

^In terms of what's related to investing, the way stocks have traded (both down and up) has been quite spectacular but this technical aspect is difficult to handicap. The virus (in the grand scheme of things and from a long term point of view) is truly a blip in the chart and dealing with this really is not rocket science. But i never thought this topic would become so interesting, including from the point of view of human nature.

 

FL, AZ, TX, GA are not that different from NY, NJ, MA or even California from the outcome point of view, it's more along fifty shades of grey. The excess mortality (if that's a variable you consider in your value system) shows very poor patterns in the four former listed states and a strong case can be built that most of the poor aspect of the record is due to a series of unforced errors that happened during the community spread phase.

 

The NY data that Investor20 referred to is quite unreliable from a population point of view, especially the first results. The antibodies do tend to wane and not all 'cases' seroconvert (although most do) so the better numbers (more tests) happened later on and may even have underestimated the 'true' level of seroconversion in the general population (Spekulatius referred to a better study (sampling problems too but much more robust) involving dialysis patients and the study suggested antibody levels at 33.6% for the NY area). Still, the antibody levels varied very significantly by ZIP code areas within NYC and this may contribute to increasing cases in some places presently (clusters with high and rising positivity rates in some neighborhoods).

 

It's hard to discuss herd immunity when people use different definitions (sometimes wildly so). The strict definition based on the initial theorem is not useful as it assumes a homogeneous population. Covid transmits heterogeneously and in clusters so a lower percentage than the theoretical number is expected. This aspect has been validated quite nicely when insufficient stock of vaccines is available for a given population. The more relaxed definition, the more a population is exposed to continued community spread and excess mortality over time. In fact, the definition of herd immunity used by some here would imply that herd immunity has been achieved for influenza (the number of cases that were much higher in the early 20th century have come down and have pretty much stabilized for the last 50 years or so). A vaccine, as a tool, is used for influenza but the effect of the vaccine could be allocated to the virus mutating (something that CV is less likely to do). An interesting thing about the flu is that this year's numbers appear to be unusually low and it's reasonable to suggest that behavior changes have something to do with it...

 

An interesting feature is that those who have opinions against various forms of lockdowns (reasonable debate) also tend to resist basic aerosol hygiene measures (mask, distance etc) or the use of vaccines which are very low cost solutions at the population level. It is puzzling. Another interesting feature is that those who push for (and say we have reached, in a binary way) herd immunity suggest the New York example (one can forget who to blame for this part of the argument and let's assume that NY results are what they are). Whatever caused NY results, in order to reach similar levels of immunity elsewhere, this would imply additional deaths over time in areas of lower immunity or lower virus penetration in the population. It's hard to figure out how to reach similar levels of immunity elsewhere and not having significantly more deaths given the imbricated and dynamic nature of our modern societies, even if the excess burden could be alleviated partially somehow through thoughtful and effective policies. Even if herd immunity needs to be reached somehow on a global basis, it has become clear that the price to pay leading to this path, at least so far, has decreased over time, suggesting that time is money in this case.

[Spekulatius]

^ It is also puzzling that there is a group of people even here that believe that herd immunity is inevitable, yet would not take the vaccine.

 

It seems to me they it should be clear, that catching the live virus in the wild in a totally uncontrolled setting as far as dose and delivery is concerned is the worst option of all.

Getting a vaccine that is not a live virus (so it can’t replicate) in a controlled setting and with hopefully known safety data should be much better in almost any scenario, even if the vaccine isn’t perfect in terms of efficacy (catching the virus naturally sure isn’t perfect either).

 

Getting a vaccine is surely more cost effective than an ICU stay and getting infusions of MAB and Remdesivir.

[MrB]

^ It is also puzzling that there is a group of people even here that believe that herd immunity is inevitable, yet would not take the vaccine.

 

It seems to me they it should be clear, that catching the live virus in the wild in a totally uncontrolled setting as far as dose and delivery is concerned is the worst option of all.

Getting a vaccine that is not a live virus (so it can’t replicate) in a controlled setting and with hopefully known safety data should be much better in almost any scenario, even if the vaccine isn’t perfect in terms of efficacy (catching the virus naturally sure isn’t perfect either).

 

Getting a vaccine is surely more cost effective than an ICU stay and getting infusions of MAB and Remdesivir.

Not sure that's true if you vaccinate the 99.9% that would not have died from it anyway or the 98% that would not have contracted the virus anyway v the 0.01% on which you will have to spend for the ICU stays, infusions and what not.

[Cigarbutt]

^ It is also puzzling that there is a group of people even here that believe that herd immunity is inevitable, yet would not take the vaccine.

It seems to me they it should be clear, that catching the live virus in the wild in a totally uncontrolled setting as far as dose and delivery is concerned is the worst option of all.

Getting a vaccine that is not a live virus (so it can’t replicate) in a controlled setting and with hopefully known safety data should be much better in almost any scenario, even if the vaccine isn’t perfect in terms of efficacy (catching the virus naturally sure isn’t perfect either).

Getting a vaccine is surely more cost effective than an ICU stay and getting infusions of MAB and Remdesivir.

Not sure that's true if you vaccinate the 99.9% that would not have died from it anyway or the 98% that would not have contracted the virus anyway v the 0.01% on which you will have to spend for the ICU stays, infusions and what not.

It does come down to an NPV calculation. The basic inputs involve comparing health costs related to testing, hospitalization, intensive care costs etc + adjusted quality of life years lost with the cost of vaccines at large. An interesting feature with the evolution of the virus is that younger cohorts (45-69) have been involved more over time and even if only a small fraction of them need costly care, contrary to the older cohorts where it becomes rapidly clear who is going to make it or not, younger cohorts will tend to 'fight' and become chronically lodged in an ICU bed. Again, a small number of cases may end up costing more than all the rest. But the challenge is to integrate indirect costs and some of them are based on values. Good luck with that, especially these days.

You may want to note that applying your train of thought requires to ask very difficult questions about the present status of healthcare. For example, using your template, the accepted practice to use yearly recurrent influenza vaccines should be abandoned. Also, concerning new antibiotics and new anti-cancer agents and many other areas, the new drugs coming to market have, for decades now, brought very marginal improvements (if any) and have come with high costs. Interestingly, the sponsors (typically private and profit-motivated) looking to harvest a 'reasonable' return on investments will calculate very optimistic NPVs, including for vaccines.

Also, if you want to use a cold, rational and cost-based approach, you may want to consider that simultaneously going for Covid vaccines while aiming for herd immunity in a population unlikely to adopt vaccines at a large scale is a negative NPV proposition.

Early vaccines were clear value propositions. Over time, as with many things, it looks like a large part of forward returns have been pulled into the present. Anyways, calculating NPVs using negative interest rates is becoming the norm so who cares?

[KCLarkin]

Arizona:

https://www.cdc.gov/mmwr/volumes/69/wr/mm6940e3.htm?s_cid=mm6940e3_w

 

The number of COVID-19 cases in Arizona stabilized and then decreased after sustained implementation and enforcement of statewide and locally enhanced mitigation measures, beginning approximately 2 weeks after implementation and enforcement of mask mandates and enhanced sanitations practices began on June 17; further decreases were observed during July 13–August 7, after statewide limitations and closures of certain services and businesses.

 

AKA "herd immunity"

 

 

 

[orthopa]

Remember when people were getting arrested for walking alone on the beach? We have come so far as a society.

[Castanza]

Remember when people were getting arrested for walking alone on the beach? We have come so far as a society.

 

What ever happened to flatten the curve? I guess it was just an infinite limit asymptote.