Random discussion of Covid-19 not specifically related to restaurants or food

[DoctorChow]

Ten more closely-spaced stages would be a first step in the right direction, IMO.

I agree that more and better data are needed to inform decision-making. So whatever became of “pool” testing?

In SD, testing capacity (due to supplies) is stretched to the point that tests are now going to revert to only symptomatic individuals and health care personnel. Or mostly, anyway. The result will be a skewed and misleadingly higher reported positivity rate. I continue to believe in random testing of the overall population, but of course those with symptoms really should be tested. So how to interpret the data under these circumstances?

Perhaps a metric other than the rolling average “positivity rate” should be considered, such as the hospitalization rate, for deciding on the timing of incremental changes.

In my opinion, business closure formulas like those in CA that are based on localized outbreak clusters and prescribe a “step-function” shut-down that chokes off entire business sectors for semi-arbitrary fixed intervals (based only on max infection/recovery times), are simplistic, mindless B.S.

In SD County, the number of hospitalizations has indeed been increasing since the week of June 22, but the number of hospitalizations relative to active, confirmed cases has hovered at about 10% for months, as new patients have come and gone .Our excess hospital capacity headroom is still very good.

In any case, there has to be a better way to govern things than telling all of the people in targeted business sectors that they will abruptly have no livelihood at all, with one day’s notice or less.

And surely there has to be a better way to even out the pain, rather than abrupt full-open or full-closed (for three weeks), for some. I think most businesses would understand and go along with that as brotherhood in the larger community.

As a state and as a country we really have to come to understand that “full stop, wait period, full start” is unstable and costing lives and livelihoods.

Once again I’m going to suggest this article to all. The sample at the end illustrating instability with On-Off control is particularly salient. And this was published in mid-April.

How Control Theory Can Help Us Control COVID-19

It’s mostly a verbal discussion, very little math, about the history of covid controls and what might have been – and presumably could still be. Easy and interesting to read, and very clearly articulated.

[There are a many edits and additions in my posts sometimes because I “compose at the piano”. This one is a record, though.]

[DoctorChow]

@DoctorChow

those with symptoms really should be tested. So how to interpret the data under these circumstances?

Perhaps a metric other than the rolling average “positivity rate” should be considered, such as the hospitalization rate, for deciding on the timing of incremental changes.

Testing as it’s done now, with a seven day delay to results, will find some people who are probably still infected, but not likely all. The “rolling 14 day average” of positivity rate helps to smooth this out to some extent, but I have two other issues with testing as it’s currently being done.

First, a given person’s test result may come back negative, based on the day they were tested. They could in principle become infected and contagious the very next day after their test without any form of detection.

Second, for now the people in SD County being tested are those showing symptoms (plus health care workers and high-risk individuals). Limiting those tested to this cohort will obviously result in a higher positivity rate among those tested, leading to decisions that could be excessively heavy-handed (abrupt “Off” and delayed “On”)

[DoctorChow]

@DoctorChow

So whatever became of “pool” testing?

I see that the FDA has approved pool testing of up to four people, as of today. That’s a very good idea in my opinion, and the max pool size is probably OK. Even two people in a pool would greatly increase the overall test results rate (and might be even better than four because a pool size of two wouldn’t dilute the samples as much and would minimize false positive pools by the largest possible amount).

Perhaps two pools of two people each, one carried out in the manner done now (those in line) and the other fully randomized over the entire population, would be an improvement. The latter would give a snapshot of the actual amount of prevalence of the disease at a given time, IMO.

[robert]

When the positivity rate is in single digits, a pool of two would be wasteful. E.g. if the positivity rate is 5%, that’s one out of 20.

WIth a group of four, for every 20 people, Quest does five tests, one comes back positive, they need to retest four, that’s a total of nine.

With a group of two, Quest does ten tests, one comes back positive, they need to retest two, that’s a total of eleven.

That needs to be adjusted slightly for false positives, but for a 5% positivity rate the sweet spot is still probably four tests.

Quest probably has a formula for this and they can just plug values into a spreadsheet to get the optimal pool size.

https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-issues-first-emergency-authorization-sample-pooling-diagnostic

[DoctorChow]

I hadn’t run any of the math, so the numbers in your example are interesting – and especially germane in SD County because the positivity rate here is not far (at the moment) from the value you chose.

And yes, no doubt Quest has done their homework on this. (Well, at least I hope so.)

[DoctorChow]

Wishful (on my part) statement by Dr. Fauci:

"The patchwork of out-of-phase, state-mandated controls has not worked in our country.

Based on all of the scientific and engineering knowledge available at this time, I am very strongly recommending that the governments of all states simultaneously institute the following state-wide policy as of Aug 1, 2020:

1. Uniformly implement the science and engineering-based feedback controls that I and other epidemiologists and engineers have designed, evaluated, and endorsed. These regard highly flexible and responsive obligatory social controls enacted to control aggregate physical distancing; airborne transmission; movement and gatherings; and business operations. These measures will lead to our recovery in health and social-economic stability in the shortest amount of time. Specific details will follow shortly

2. Discontinue all state- and locally-mandated controls in favor of the remedies that my Institute will specifically prescribe, in order to maintain uniformity and stability throughout the country.

3. Adhere to all of all specific updates from our Institute which could be announced as frequently as twice a week; be watchful for these

Taking this unified nation-wide action now will reduce total US deaths from the covid and shorten the time for our personal, social, and economic recovery. I’m sure all will participate and cooperate because we all want this to calm down."

I wish our Covid Doctor in Chief would say something more specific like that, rather than just “wear a mask” and “wash your hands” and stand six feet apart. And in effect, “a vaccine in January is hopeful but only maybe possible. I hope. Cautiously.” And “yeah, things are gonna get worse”. Yada, yada, yada…

[honkman]

Either you are not really aware how politics work here in the US or you still haven’t understood that your approach would be actually worse than what is already happening

[DoctorChow]

Why Trump's failure to lead national response prolongs coronavirus crisis

The 50-state free-for-all seat-of-the-pants approach in the US is a global laughing stock.

[DoctorChow]

@DoctorChow

Anyway, this virus might die out and go away on its own come late spring.

Hard to believe, looking back, that I thought this was possible, even probable, on Feb. 24.

I’d been comparing covid to other widespread epidemics that have lasted just a couple of months, including the two-month duration of the largest wave of the Spanish flu.

How naïve of me, thinking back. Masks hadn’t been discussed very much at all at that point and I was very surprised to see someone wearing one. And I’d never worn one at any time before in my entire life.

Even through childhood with things like measles, polio, chickenpox, mumps, flu, tetanus, whooping cough going around.

Not to mention all of the more recent pandemics.

Now it feels like Feb. 24 was in a different life and a different lifetime…

And yes, I wear a mask.

[Sgee]

[DoctorChow]

Back in January and February, no one at any level of government or in any health institute was recommending masks. We had no leadership or foresight at all at the federal level. (We still don’t, actually.) When we finally had local government mandates, I for one, followed all of them and still do. At first, none of us, individually, had a clue as to what to do or not to do. I cut way back on my normally frequent restaurant patronage at the time, but that was about all.

[moonboy403]

@DoctorChow

no one at any level of government or in any health institute was recommending masks

I feel that the decision was more of a political one since there were mass shortages as it was for even health professionals so asking 328 million people to fetch masks when there was none wasn’t practical.

[DoctorChow]

It was certainly true that the public was being asked not to buy N95 masks due to their critical need in healthcare settings. I recall that when it started to look like we were all going to be asked to wear masks, they were indeed very hard to find. I bought my first five paper ones at a liquor store – for $10 – and at least had those on hand when we were finally asked to wear face coverings. I can’t even recall exactly when that was – seems like forever ago.

[moonboy403]

https://thehill.com/policy/healthcare/508906-fauci-defends-past-recommendations-following-conservative-attacks

“Back then, the critical issue was to save the masks for the people who really needed them because it was felt there was a shortage of masks,” Fauci said. “Also, we didn’t realize at all the extent of asymptomatic spread.”

[Sgee]

@DoctorChow

Back in January and February, no one at any level of government or in any health institute was recommending masks. We had no leadership or foresight at all at the federal level… …At first, none of us, individually, had a clue as to what to do or not to do.

Masks… respiratory protection when exposed to harmful particles, germs, bacteria etc.

Ever wonder why medical professionals use it…?

It’s even immortalized in Halloween costumes.

From the NIH

"You can catch the flu when someone near you coughs or sneezes. Or, if you touch something the virus is on, like Ellen and Jack’s phone or doorknob, and then touch your nose or mouth, you could catch the flu . The flu virus can live on a surface like a book or doorknob for a number of hours."

The frontline workers in NYC were just wearing PPE for shits and giggles to treat Covid patients

Apparently this shit truly requires a PhD in theoretical physics to deduce…!

[DoctorChow]

Cute kids (and a dramatic photo), but masks were never normally worn for routine medical exams or procedures. Surgeons wear masks as do those treating infectious or potentially infectious patients. What the NIH says is true, of course, but it doesn’t at all negate the quote in my post that you responded to.

[Sgee]

Good luck if you’re ever stranded in the wild (god forbid) without an explicit instruction manual

[Sgee]

@DoctorChow

Surgeons wear masks as do those treating infectious or potentially infectious patients.

Hazardous procedure

[Sgee]

Typical surgery

Covid ICU

[DoctorChow]

OK, and dentists too. (BTW, I note that in the photo you posted, the guy doesn’t have his nose covered.)

The eventual recommendation to wear masks was highly unusual. We’ve never been asked as an entire nation, or by state or local government during flu season each year to wear masks. Just to follow the common-sense steps in the NIH quote that you posted earlier. It’s not rocket science or theoretical physics. Somehow I’ve survived through almost eight decades of flu (and several other communicable diseases) and the government has never before recommended that everyone wear masks. That’s one reason there was a major shortage when our government finally did ask everyone to wear one for the covid: We had no personal reserves, no national or local stockpile, and inadequate domestic manufacturing capability. The government has recommended getting a flu shot every year (and vaccinations for other diseases as necessary), which I’ve done for as long as I can remember (although 50% of the rest of the US population declines to do so, year after year).