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A Third Solution

paulbuchheit.blogspot.com

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Re: A Third Solution

#151

Post by ggreer »

I really hope this works. Without some new testing technology, I just don't see how we can stop the spread of this disease. A month ago, the US did about 100,000 tests per day. Yesterday, the US did about 200,000 tests. Growth in testing started off as exponential but now it looks linear.[1] Even if testing capability doubled every month, it would take 8 months before we could test every American once a week. (200,000 * 2^8 == 51,200,000, which is 15% of the population.)

It only took a couple of months for 20% of New Yorkers to get infected.[2] If we assume that half the population will get this disease over the next two years, and we assume an infection fatality rate of 0.3%, that's around 500,000 deaths. (328,000,000 * 0.5 * 0.003 == 492,000). Those are optimistic projections. The IFR is likely higher and the R0 is somewhere between 3 and 9[3], so that means at somewhere between 60% and 90% of the population needs to be infected before we get herd immunity.[4]

Unless there are radical improvements in testing and/or treatment, I think we'll end up with at least 500,000 deaths in the US. That would mean we're about 10% of the way through this catastrophe. So strap in, it's gonna be a long ride.

1. https://twitter.com/COVID19Tracking/status/12538071759457443...

2. https://twitter.com/NYGovCuomo/status/1253353516803993600

3. https://wwwnc.cdc.gov/eid/article/26/7/20-0282_article

4. For the relationship between R0 and herd immunity, see figure 2 of this paper: https://academic.oup.com/cid/article-pdf/52/7/911/847338/cir...

Re: A Third Solution

#152

Post by jhayward »

tlb wrote: post #131
jhayward wrote: post #119

Earlier quoted context omitted.

> The false positive rate of lockdowns is 100%. If that were true lockdowns would make absolutely no difference in R0. Clearly, they do make a difference.

I don't follow your reasoning. Maybe we use a term differently? Here's how I understand them: - A false positive means that a test shows someone is infected when they are not. For most tests that's somewhere between 0.1% and 2%. - Lockdown means everyone stays at home. Different from PB's plan, where only people with a recent positive test stay home. - R0 (technically Re) is the expected number of people each newly i…

Re is a different number based on what proportion of the population is immune. Here we are talking about R0.

The point I am making is that some of the people who are on lockdown are truly positive for the virus. That’s why it works. They don’t have the opportunity to spread it outside their habitation unit.

Re: A Third Solution

#153

Post by swang75 »

An honest query by a non-medical professional as I'm sincerely curious...

Paul advocates daily saliva-based testing, but as an intermediary imperfect, but "better than nothing" measure, what are the benefits and drawbacks of requiring people entering public shared spaces to have their body temperatures taken via handheld temperature guns or infrared monitors, a measure that's already taking place in much East Asia (Greater China, Japan, Korea, etc.) in public shared spaces like malls, restaurants, office buildings? My understanding is that these methods are not as accurate as direct thermometers or Paul's saliva-based test; nonetheless, they would detect a good portion of mildly symptomatic people and also have the benefit of externally signaling to the populace to continue "sheltering-in-place" if they have a fever.

Is there any issue with supply chains? Or is there scientific evidence disproving the effectiveness of this precautionary measure that's already in place in so many regions that have already seemed to have crested the first wave of the pandemic?

Re: A Third Solution

#154

Post by dekhn »

marcell wrote: post #21
johnnyo wrote: post #12

Earlier quoted context omitted.

The things that generally kill Americans (heart disease, cancer, car crashes, diabetes, etc) aren’t contagious, so this is a bad analogy.

No analogy is perfect, but people need context to understand fatality rates, and see what risk is acceptable. Society doesn't have a goal of 0% death rates. We all accept some risk of death as a cost of continued existence. New data is showing that the fatality rate from covid-19 is more like existing risk we were all previously exposed to in the course of our existence, and not like a second version of smallpox.

This more or less sums up my position. Thank you for stating it. I think the news media played a big role in amplifying the risk in a very uncertain early period that made people treat this differently from other risks that affect us and many of the arguments right now are happening because some poeple believe the goal of society is to reach 0% death rates.

An important thing to recognize is that the disease itself is not an existential threat (even smallpox wasn't; even the plague wasn't!), but our response to it skirts creating one.

Re: A Third Solution

#155

Post by clairity »

arcticbull wrote: post #134

> This could be a reason why so many otherwise young and healthy doctors and nurses have been killed by this virus. This isn't well supported by data. In the sense that (a) young people just aren't particularly affected any more so than with the flu (old and sick people of course are much worse off) and (b) in Italy's data, no health professionals under the age of 49 died. There have been some deaths outside Italy bu…

that’s one of a number of misleading assumptions stemming from the core presumption that

> “It is my belief that the best cure for any disease is to avoid the disease.”

on top of that, even assumptions about how to do that (avoid the disease) at scale are often mistaken. that’s a big credibility hurdle.

with that said, mass and frequent testing would be a method to quarantine the infected, and get treatment for the most vulnerable (like the elderly), faster (surveillance implications notwithstanding), which would drop R0 like a rock.

Re: A Third Solution

#156

Post by s0rce »

stonogo wrote: post #88

Not only is it completely unrealistic at scale, the specific approach in the blog post is wildly impossible at all. It requires screeners to directly manipulate saliva samples; this is dangerous in a pandemic. The assays referred to (lazily) in a Google Scholar search are almost overwhelmingly antibody assays; this does not allow the screener to differentiate between "has COVID-19" and "had COVID-19". Also, there is…

Some of the assays do appear to functionalize the surface to directly bind and detect viral particles. I have some familiarity with SPR but haven't used it and not to detect viruses (otherwise experienced with surface science).

Re: A Third Solution

#157

Post by vikramkr »

Mikeb85 wrote: post #132
newacct583 wrote: post #112

Earlier quoted context omitted.

Not to quibble too much with most of your criticism, but this one seems minor and trivially solved: > this does not allow the screener to differentiate between "has COVID-19" and "had COVID-19" As a policy matter, this doesn't rule out the use of the test in a pandemic management protocol at all, it just changes how it needs to be administered. For example it might require that people who are antibody-positive have a…

> people who are antibody-positive have a standardized note confirming recovery How do you prove recovery if you were never proven sick first? As an example, I had all the symptoms of Covid in late February, the same severity many people in my age group described, yet was never tested since our health authority dropped the ball and claimed community transmission wasn't a thing back then. If I tested positive for anti…

There are different subtypes of antibodies that you test, some that emerge early in infection and others that emerge later. The current understanding is that the later emerging antibodies being positive generally indicates that you are not only recovered but also immune from the virus and can donate your own convalescent plasma to be used as a drug for people with the infection. If you test positive for early antibodies you are assumed to still be undergoing the course of the infection.

Re: A Third Solution

#158

Post by jhayward »

arcticbull wrote: post #149
jhayward wrote: post #136

Earlier quoted context omitted.

You repeat the fantasy that the more vulnerable population is separable from the less vulnerable. As well you omit the size of the vulnerable - everyone who is obese, diabetic, hypertensive, or cardiovascular diseased, or immunocompromised. The first is just a fantasy - no one has an actionable plan to do it. The second proves the size of the problem, which exacerbates the difficulty.

Again, as always, Sweden seems to be doing it just fine.

Sweden isn’t proof of anything, please stop using it as though it is.

Your claim is that the vulnerable can be “holed up” while everyone else goes about their happy business. There is no such thing, and I challenge you to provide the details and success as measured by per-demographic death rates of any proof you may have.

Re: A Third Solution

#159

Post by marcell »

erik_seaberg wrote: post #130
marcell wrote: post #123

Earlier quoted context omitted.

There's a bit of gish gallop and vitriol here. First, the .75% mortality rate is a one-time hit. It likely pulls some deaths forward, so the incremental death rate is maybe .5% in a single year. Again, this is terrible, and sad, but we should be mindful and accurate with numbers. Second, people make lots of choices that increase their mortality risk by .5%. For example, lots of people eat at McDonald's on a regular b…

I can understand risk per time period, but what does "0.5% lifetime mortality risk" mean? Does my lifespan get 0.38 years shorter?

Yes, basically that. Your expected lifespan is lowered by 0.5%, which is around 0.38 years.

Re: A Third Solution

#160

Post by not_a_moth »

A fourth way: We throw as many resources as we can at sampling undiagnosed populations, like the recent NYC study that suggests 20% of the city (10% of the state) has antibodies already.

We could get real confidence that it's safe enough to return to normal, acceping that COVID is a new disease that's just going to be around, the 5th coronavirus that we deal with seasonally.

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