COVID-19 - Facts and Information Only Topic

[Hapless Bills Fan]

It had been rightly pointed out in this group that we really don't know what we're putting on our faces and how well it works to block droplet transmission.

 

Well - Now we do, thanks to these folks who built a low-cost test device with a laser, a box, and a cell phone to assess how well different masks did at blocking particles.

Note: they are blocking particles the mask wearer EMITS, not particles the mask wearer breathes IN (I would expect the N95 to kick butt and take names there)

 

https://advances.sciencemag.org/content/early/2020/08/07/sciadv.abd3083?fbclid=IwAR2nZmIlAggEMgJjLUISYaU05YRQA-iwqOkgTZ0Bl5GdHN-tOT4gIgDvjfs

 

1) Fleece neck gaiter literally worse than nothing

2) Bandana pretty bad, cotton knit mask a little bit better

3) N95 and surgical mask the best, but pretty well everything else blocked at least 80% of the particles emitted by the mask wearer

 

 

 

[SlimShady'sSpaceForce]

@Hapless Bills Fan

 

https://www.yahoo.com/news/why-does-covid-19-strike-110000273.html

 

I tried to find the direct link to the Miami Herald but quickly gave up. 

 

Why does COVID-19 strike some and not others? Fauci sees an answer in new study

 

The discovery, which found potential signs of immunity in people who had previously been exposed to other types of coronavirus, could also expand the hunt for a long-lasting COVID-19 vaccine.

 

Fauci and other scientists said the study published in Science this month held promising findings for understanding why some individuals exposed to COVID-19 for the first time have a modest reaction to the virus.

 

The study found that the immune systems of roughly half of its subjects appeared to remember past exposure to other, prevalent coronaviruses, including variants of the common cold, equipping them to respond more quickly to a COVID-19 infection once it appeared.

 

[Edit: Thanks for looking.  This work builds on and expand observations in a paper published in Nature, linked above.  Here’s a link to this study's paper.

Key Quote . We demonstrate a range of pre-existing memory CD4⁺ T cells that are cross-reactive with comparable affinity to SARS-CoV-2 and the common cold coronaviruses HCoV-OC43, HCoV-229E, HCoV-NL63, or HCoV-HKU1. Thus, variegated T cell memory to coronaviruses that cause the common cold may underlie at least some of the extensive heterogeneity observed in COVID-19 disease.

 

For an explanation of immune function that may put this in context, check out this article published in the Atlantic and linked in the discussion thread.]

[Hapless Bills Fan]

press release about successful results in RLF-100 clinical trial.
NeuroRx, Inc. and Relief Therapeutics Holdings AG (SIX:RLF, OTC:RLFTF) “Relief” today announced that RLF-100 (aviptadil) showed rapid recovery from respiratory failure in the most critically ill patients with COVID-19. At the same time, independent researchers have reported that aviptadil blocked replication of the SARS coronavirus in human lung cells and monocytes.

RLF-100 has been granted Fast Track designation by FDA and is being developed as a Material Threat Medical Countermeasure in cooperation with the National Institutes of Health and other federal agencies. Further research will be conducted.

 

They appear to have not published the trial results yet, but it appears to be legit.  Drug is also known as aviptadil.  It is being made available by the FDA under an "Expanded Access Program", which is a program to make investigational drugs that are not yet approved but have had positive clinical trial results available to critically ill patients.

Here's a preprint about it

 

What is this avaptadil or RLF-100 drug?  It's a form of Vasoactive Intestinal Peptide or VIP. 

Here's their blurb on how it may protect the specific lung cells attacked by Sars-Cov2 virus during severe covid-19 disease, which produce the surfactant that protects the surface of the lungs:

https://www.neurorxpharma.com/our-services/curious-about-how-rlf-100-works/

 

"The clinical findings may be based on evidence that VIP inhibits the replication of the SARS-CoV-2 virus in human lung cells and immune cells (monocytes). The work was reported by Brazilian researchers working in a level-4 biocontainment laboratory.³ The same researchers reported a case-control study in which patients who survived being on ventilators for COVID-19 had significantly higher levels of VIP in their blood than those who died of respiratory failure."

 

Very hopeful that some combination of VIP, remdesivir, and dexamethasone will decrease death rates and shorten recovery times from covid-19

 

16 hours ago, Buddo said:

Is this a new product, or something that has been around for a while?

 

It's been around since the late 90's as a potential treatment for Erectile Dysfunction.  But it had to be injected, which made it a poor competitor for viagra, and it had some safety concerns which are probably not a concern for a life-threatening condition such as a covid-19 patient on a ventilator, so it was never pushed to approval as a drug.  It has been through a clinical trial as a treatment for ARDS.

https://www.dailymail.co.uk/news/article-8599731/Erectile-dysfunction-drug-aviptadil-beat-Covid-19-experts-believe.html

(this article has a list of potential treatments undergoing current study at the end)
https://seekingalpha.com/article/4367483-relief-therapeutics-discovers-promising-covidminus-19-killer

(investment article but with a good explanation of the clinical problem and how RLF-100 might work)

 

Reasonably balanced perspective:

https://www.medpagetoday.com/infectiousdisease/covid19/87990

Just to clarify - RLF-100 is a treatment that has shown promise in the lab and in treatment of a handful of patients, but the clinical trials are getting started.  So it may pan out, it may not.  But another drug that could help the recovery of seriously ill patients (in addition to dexamethasone) would be helpful.

 

[HappyDays]

On 8/12/2020 at 10:06 AM, Hapless Bills Fan said:

CDC Excess Death data.  Note that cause of death data can take weeks or months to be transmitted and recorded.  Also I'm not sure how to interpret this, but I think it's saying this excludes NYC?

 

https://www.cdc.gov/nchs/nvss/vsrr/covid19/excess_deaths.htm

 

 

 

Related:

 

 

[Hapless Bills Fan]

Thanks @Nervous Guy for pointing this out.

 

UCF group found Llama nanobodies (which function like antibodies but are much smaller) that block the region of the covid-19 spike protein needed for infection.

Nanobodies tend to be very much more stable than antibodies.

 

Research article

https://www.biorxiv.org/content/10.1101/2020.08.08.238469v1

They hope to develop a room-temperature stable covid-19 preventative that can be inhaled.    Would be cool if it works and does not cause side effects, but I think it's not as far along as UCF in-house publication about their concept makes it seem:

https://www.ucsf.edu/news/2020/08/418241/aeronabs-promise-powerful-inhalable-protection-against-covid-19

 

 

[Mike in Horseheads]

FDA has approved a saliva based test that was funded by the NBA and NBAPA. 

 

The test, known as SalivaDirect, is designed for widespread public screening. The cost per sample could be as low as about $4, though the cost to consumers will likely be higher than that -- perhaps around $15 or $20 in some cases, according to expert sources.

 

https://www.espn.com/nba/story/_/id/29667299/fda-allowing-saliva-based-test-funded-nba

[Edit: some more info on this

General article on saliva testing https://www.the-scientist.com/news-opinion/saliva-tests-how-they-work-and-what-they-bring-to-covid-19-67720
Test U of Illinois plans to use https://www.biorxiv.org/content/10.1101/2020.06.18.159434v1.full.pdf

Yale/NBA developed test https://www.medrxiv.org/content/10.1101/2020.08.03.20167791v1

Note that the Yale and the U of Illinois test skip a step in the standard Covid-19 test - RNA extraction - but are still RT-PCR based tests]

 

 

 

 

[Mr Info]

This may be of interest to some.

‘COVID-19 vaccine development and a potential nanomaterial path forward.’
 

Published in peer-reviewed Nature Nanotechnology in July. Department of NanoEngineering, University of California San Diego, La Jolla, CA.

Contains some good vaccine background summary and you do not have to be a research scientist to comprehend the gist of it.

 

https://www.nature.com/articles/s41565-020-0737-y

 

[Edit: it's a good article but note that it was:

• Received25 April 2020

• Accepted22 June 2020

• Published15 July 2020

thus the information about where different vaccines are currently in clinical trials is out of date.  Thanks!]

[Hapless Bills Fan]

Slightly different covid-19 test technology.

 

https://www.technologynetworks.com/diagnostics/news/new-test-can-diagnose-covid-19-in-20-minutes-338629?fbclid=IwAR0DbtgIJyOlVWBcI0WwH-_zbHU4vSfHRwd_ZjU-P2sWNFtMGtPQ2KQSExo

 

 

 

Here's a general article about the LAMP technology (Loop Mediated Isothermal Amplification).

Unlike PCR, which requires cycles at different temperatures, LAMP only requires one temperature.

 

Here's the paper on the test itself. (That's a preprint, it's being published in the journal Medical Microbiology now) Despite the headlines, the N1-STOP-LAMP covid-19 test is less sensitive - only 87% of the positives the RT-PCR test detects.  But it's faster, less labor intensive, and less expensive.

[shoshin]

Economist video interview with Bill Gates. 

 

Highlights:

 

- Change of US admin won't affect Covid outcome.  

- Says the next admin (Trump or Biden) will face the challenge of getting Americans to take the vaccine quickly and get rid of the virus. I see this too. Lots of people just won’t take it, and this thing will be prolonged.

- He is not worried that the vaccines will fail in Phase 3 tests. Says of the 6 candidates, several will work. Fully optimistic about it. There are the left and right anti-vaxxers, but also a new group of people who are afraid of “new vaccines.”

- 4 candidates are very cheap ($2-3/dose) and should make it to developing world, but may not get there quickly because the US isn't leading to help those countries like it has in the past. 

- Phase 3 testing should be done by Q4. 

- timeframe to herd immunity (30% in his view) counting people who have had it + cross-immunity to other coronaviruses + vaccines: In the US, he says sometime 2021 we will be largely over it. 2022 rest of the world.

- key thing is that this has to work well with elderly. Phase I candidates seem to be doing well with older folks (notes that flu vaccines sometimes work poorly for elderly)

- is amazed about the conspiracy stuff...could not have predicted so many people could adopt this conspiracy mindset

 

Edited August 18, 2020 by shoshin

[Hapless Bills Fan]

This is important.  More evidence that T-cell response, including memory T-cells, is provoked in covid-19 patients who have no or weak anti-covid-19 antibodies

Paper from group at Karolinska Institit in Sweden, accepted in Cell (very good journal):

https://www.cell.com/cell/pdf/S0092-8674(20)31008-4.pdf?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867420310084%3Fshowall%3Dtrue

 

More readable Commentary on the article

https://www.technologynetworks.com/immunology/news/sars-cov-2-immunity-likely-to-be-higher-than-antibody-testing-has-shown-336861?fbclid=IwAR0qnz37qV_NAH9pVFCcbNd_JNWCLblh4v1CCGqDo9JIbN8RjavFwremsoI

 

TL;DR: Importantly, SARS-CoV-2-specific T cells were detectable in antibody-seronegative exposed family members and convalescent individuals with a history of asymptomatic and mild COVID-19. Our collective dataset shows that SARS-CoV-2 elicits robust, broad and highly functional memory T cell responses, suggesting that natural exposure or infection may prevent recurrent episodes of severe COVID-19

Point of this cartoon-like summary figure (supported by a *****-ton of data only an immunologist could love) is that they found "memory-type" T-cell response specific to covid-19 in people who were exposed or had mild disease, and didn't have strong or persistent antibody response.

 

[DefenseWins]

https://profootballtalk.nbcsports.com/2020/08/20/georgia-state-quarterback-out-for-season-with-covid-related-heart-ailment/

 

So much for the young being invincible as far as Covid is concerned...

[Hapless Bills Fan]

Ok, this one has me scratching my head.

 

CDC travel guidelines have changed.  They have dropped the recommendation to quarantine for 14 days when you return from travel:

You may have been exposed to COVID-19 on your travels. You may feel well and not have any symptoms, but you can be contagious without symptoms and spread the virus to others. You and your travel companions (including children) pose a risk to your family, friends, and community for 14 days after you were exposed to the virus. Regardless of where you traveled or what you did during your trip, take these actions to protect others from getting sick after you return:

• When around others, stay at least 6 feet (about 2 arms’ length) from other people who are not from your household. It is important to do this everywhere, both indoors and outdoors.
• Wear a mask to keep your nose and mouth covered when you are outside of your home.
• Wash your hands often or use hand sanitizer (with at least 60% alcohol).
• Watch your health and look for symptoms of COVID-19. Take your temperature if you feel sick.

Follow state, territorial, tribal and local recommendations or requirements after travel.

They still note that "you and your travel companions including children pose a risk to your family friends and community for 14 days"

 

In a number of studies, the "attack rate" (% of close contacts of an infected person who become ill themselves) range from 12% within the home to 40% (I think most of these are upthread, but I'll loop back and reference tomorrow).  The within-home attack rate may be  5x-20x higher than outside-home.

Given this, and the fact that the CDC notes returning travelers pose a risk to those close to them for 14 days, the focus on "outside the home" and "other people who are not from your household" while removing the advice to quarantine, is puzzling to understand. 

 

The revision is from last week and has received relatively little press coverage.  I could not find any interviews giving a scientific rationale for the change.

Gentle reminder that if you're moved to discuss or expostulate, please copy the link to this post and discuss in discussion thread.

 

 

 

[Hapless Bills Fan]

This is a practical (and obviously for football fans, applicable) experiment with 2000 people in Leipsig, Germany

 

https://wgntv.com/news/coronavirus/thousands-crowd-into-indoor-concert-in-german-experiment-on-how-to-return-to-normal/

 

Researchers in the German city of Leipzig staged a 2,000-person experimental indoor concert on Saturday to better understand how Covid-19 spreads at big, busy events, and how to prevent it.   At the gig, which featured a live performance from musician Tim Bendzko, fans were given respiratory face masks, fluorescent hand gel and electronic “contact trackers” — small transmitters that determine the contact rates and contact distances of the individual experiment participants.  Using data from the contact trackers, scientists from The University of Halle will monitor the number “critical contacts” had by each participant during specific times and locations, while the residue left by fluorescent hand gel will identify frequently touched surfaces. Researchers hope to use the data to find ways to bring big events back safely.
(....)

Gekle told CNN that due to a low prevalence of the virus in the states of Saxony and Lower Saxony, participating in the study was low risk for volunteers, who underwent coronavirus testing 48 hours before participation, and were wearing masks during the show. “It’s safer than flying to Majorca,” he said.

 

[Hapless Bills Fan]

Convalescent Plasma EUA. 

First, some perspective: giving patients convalescent plasma, is an old faithful, tried-and-true step taken by the medical community when there are no or few effective treatments for a novel disease.  It's been used for SARS, MERS, Ebola etc.  It seldom has severe side effects, and with other diseases, it has been found helpful.  But it's not "a historic breakthrough" or "a major therapeutic breakthrough".  For one thing, there unfortunately isn't great evidence to support its efficacy (see below).  For another, it was being used in China pretty early on in the epidemic - if we want to claim "historic breakthrough", Well Then.....

FDA memorandum issuing Emergency Use Authorization for convalescent plasma.

Scroll down a bit to get to the meat where they summarize evidence for effectiveness.

 

Some key points:

The actual randomized, controlled clinical trial evidence is very scant:

-true randomized, controlled studies only in Wuhan China and Netherlands, and they didn't show great effect

-three prospective studies where control patients were not transfused)

-4 retrospective matched cohort studies (they look at people who were treated with convalescent plasma and try to match their characteristics with untreated patients - unfortunately this is a very tricky business and the cohorts often differ in significant ways, muddying the waters)

-By "earlier in the course of the disease" they mean "seriously ill people who are or who should be hospitalized, but are not yet intubated and on ventilators"  they don't mean "Line up to get your CCP infusion right after your positive covid-19 results come back you ambulatory 94% O2sat Scum!"

 

Key quote from the Summary of Effectiveness:

Considering the totality of the scientific evidence summarized above, I agree that current data support the conclusion that CCP to treat hospitalized patients with COVID-19 meets the “may be effective” criteria for issuance of an EUA. Adequate and well-controlled randomized trials remain nonetheless necessary for a definitive demonstration of CCP efficacy and to determine the optimal product attributes and the appropriate patient populations for its use. Current evidence suggests that benefit is most likely in patients treated early in the course of the disease (e.g., prior to intubation).

In addition, as outlined in the data reviewed above from different studies, there is a potential benefit of CCP in intubated and non-intubated patients. Considering the absence of a control population in the EAP and that data from randomized trials remain limited, the lack of benefit observed in intubated patients in this study is currently insufficient to exclude potential benefit in this population. Therefore, bearing in mind the safety profile observed to date, inclusion of intubated and non-intubated patients under the EUA appears appropriate at this time.

 

The bottom line is the EUA was granted because there's enough evidence that it might be of benefit.   But the evidence that it works is not as definitive as one would like.

 

The press conference announcing the approval was highly misleading about what's known for the effects.  Pharma Blogger Derek Lowe has some rather trenchant commentary in his blog****.  Lowe knows his stuff and unfortunately, I see his points.

 

(...) The problem is that we still haven’t generated any controlled clinical data on how useful it is. The Mayo-led data that were talked about during yesterday’s press conference had no control group, making that key question impossible to really answer. This shows the perverse danger of being too free with emergency use. If you just turn everyone loose on a bunch of therapies, they will be used under all sorts of conditions and the chances of getting a useful read on any of them go down. Look at our current situation: we have data on over 35,000 patients who have received convalescent plasma, but we still don’t have a good comparison to not receiving it. It shouldn’t have happened this way.
 

I know that there was a figure of 35% being helped/saved by the plasma treatment being used at yesterday’s press conference, but unfortunately, that’s just plain wrong. FDA Commissioner Hahn used the phrase “35% improvement in survival”, but that merely makes him look like a fool (and like someone trying to keep his boss smiling) to anyone who’s capable of reading the actual paper, which is another nasty side effect of this whole affair. See this for more, and this: since the data do not have a control comparison group, we can make no firm statements about the benefit of the treatment, and the 35% number is a misunderstanding of what data we have. Sad but true.

Some background data:
The Mayo Clinic paper Hahn was apparently quoting:

https://www.medrxiv.org/content/10.1101/2020.08.12.20169359v1.full.pdf

 

There appear to be significant differences between the low-titer and high-titer arm, with the low-titer arm being significantly 1) older 2) sicker.

 

 

 

 

 

I hate writing this stuff because I know it looks so negative. 

Given the current state of treatment for covid-19, would I want convalescent plasma if someone I loved or if I myself were hospitalized with low oxygen levels?  Yes.  Yes, I would. 

Do I think it's as effective a treatment as that "35% decrease in mortality" soundbite makes it sound?  No - not based on the data we have to date.  I'm afraid that's stat mangling, and pretty misleading, and I understand the reaction of Lowe and Gaffney. 

Edit: and now Hahn himself has acknowledged as much:

 

**** and when I say "trenchant commentary", I mean I can not recall this level of critique and pungent language from Lowe, in all the years I've been reading him.  He has nothing at all against convalescent plasma - and everything against how it was hyped in the press conference.

[BillsFan4]

https://www.cnn.com/2020/08/25/health/covid-19-superspreading-boston-study/index.html
‘Covid-19 superspreading event in Boston may have led to 20,000 cases, researcher says‘
 

They’re talking about the BioGen conference at the end of February in Boston and how it could have caused 20k total cases since then and led to sustained community transmission in numerous places in MA. It also mentions that some of the event participants took covid back with them to numerous different states and a couple countries.

Link to the paper (it’s not peer reviewed yet): 

https://www.medrxiv.org/content/10.1101/2020.08.23.20178236v1.full.pdf+html

 

its an interesting read. They also looked at a breakout at a skilled nursing facility. There were multiple introductions of covid into the facility but 1 specific one led to roughly 90% of the cases at the facility.

[Hapless Bills Fan]

How pooled testing could be used to test the entire US:

https://news.cornell.edu/stories/2020/06/group-testing-could-screen-entire-us-research-suggests
 

White paper about it:
https://docs.google.com/document/d/1hw5K5V7XOug_r6CQ0UYt25szQxXFPmZmFhK15ZpH5U0/edit?ts=5e934170

 

The lead author is one of the modelers and developers of the very test-intensive plan Cornell University crafted to reopen campus.  They are planning to test 50,000 people a week (~30,000 people, some once a week and some twice a week or more) or 5,000-7,000 people per day.  The viral RNA is extracted from individual samples then 10 samples are pooled, so they're running only 700 tests per day.  The tests are being run in-house at Cornell's vet school, basically 8 - 96 well test plates per day - which is pretty much what a clinical virology lab at a good teaching hospital can handle.  We'll see how that works....So far the prevalence is very low.

 

BTW if you want to see an example of how increased testing does not lead to increased covid-19 diagnosis, check out Tompkins County at the NY Forward site

Cornell started testing arriving off-campus students in mid-July (first bump-up).  Then testing ramped up again, to >1000 samples/day, mid-August.  Tompkins County is running 0.1% positives. 

 

 

 

[Buddo]

https://www.marketwatch.com/amp/story/moderna-and-pfizers-covid-19-vaccine-candidates-require-ultra-low-temperatures-raising-questions-about-storage-distribution-2020-08-27

 

Someone posted this in the PPP thread, but I think it deserves to go here. The articles gives storage conditions for a few of the touted vaccines, and it's not pretty reading, as they need to be stored at very low temps. Means that there are a lot less places that will be able to successfully store, and hence administer, these potential vaccines. Doesn't apply to all of them, but it could well be an issue 'down the line'.

 

[Here's another article about it.  This is pretty typical for mRNA vaccines by themselves.  I don't think it's as big a deal as that paper makes out for the US.   For example, the Pfizer vaccine can be refrigerated for 24-48 hrs.  Vaccines can also be sent to community clinics in dry ice/styrofoam - the Pfizer drug substance for the vaccines got shipped off to filter and fill that way.   So vaccine for clinics at community centers can be sent there on dry ice then stored in the fridge for a 2 day vaccination clinic. It does make the supply chain more challenging, no doubt.  -94F is a -70C deep freeze, which is standard equipment at most hospitals.
https://www.fiercepharma.com/manufacturing/pfizer-moderna-s-covid-19-shot-rollouts-could-be-ice-as-analysts-question-cold  ]

[Hapless Bills Fan]

A propos of talk in the Discussion thread about the recent change in CDC recommendations to not test asymptomatic people with known covid-19 exposure, this study from CDC's MMWR (morbidity and mortality weekly report) seems relevant.

 

https://www.cdc.gov/mmwr/volumes/69/wr/mm6935e1.htm

 

TL;DR: a Maine summer camp introduced policies that prevented the sort of infection spread observed in Georgia, Arkansas, and MO summer camps.

Campers came from all over the country, including states and areas with active covid-19 outbreaks.

 

Here's what worked:

1) Asked campers and staff to quarantine 10-14 days and if possible, get tested before arrival.  4 asymptomatic infections were identified and delayed their trip to camp

2) Set up small "pods" or groups and asked campers to stay within them for 2 weeks after arrival

3) Tested 4-9 days after arrival (2-3 day turn around) - 3 asymptomatic infections were identified and isolated and their contacts were quarantined

 

These measures were employed in addition to use of face coverings, daily symptom checks, and isolating/testing campers with symptoms.

No further infections were identified during the 44-62 days camp was in session.

Non-pharmacological interventions can work to contain covid-19 without massive shutdowns. 

But they need to be applied consistently and in keeping with known epidemiological "best practice"

 

 

This summary figure courtesy "your local immunologist" Facebook account:

[Hapless Bills Fan]

I suspect this will be pretty good.  Open to the public - lectures available at any time, no need to crowd onto the server at 11:30 ET Tuesday.

 

https://biology.mit.edu/undergraduate/current-students/subject-offerings/covid-19-sars-cov-2-and-the-pandemic/?fbclid=IwAR2Spo0At8EoptV9fAD3gDrtOAqIzFceX6MF1WgFB08EO6mYmJ0LxGTWcwY

 

New Subject Offering: “COVID-19, SARS-CoV-2 and the Pandemic”

In Fall 2020, all MIT students and the general public are welcome to join Professors Richard Young and Facundo Batista as they discuss the science of the pandemic during this new class. Special guest speakers include: Anthony Fauci, David Baltimore, Britt Glaunsinger, Bruce Walker, Eric Lander, Michel Nussenzweig, Akiko Iwasaki, Arlene Sharpe, Kizzmekia Corbett, and others. The class will run from September 1, 2020 through December 8, 2020 and begin each Tuesday at 11:30 a.m. ET. See the syllabus for lecture details.

 

The class is open to all MIT students, as well as any eligible cross-registered students. The live stream will be available to the public, but only registered students may ask questions during the Q&A. To view the live stream, click on this link and type in the password: mit-covid. Miss a class? You’ll be able to view a video of the lecture on this page.

 

 

[Hapless Bills Fan]

Time to "Bite the Snake" on this 6% or whatever it is according to "Q"

 

This Forbes article does a pretty good job of explaining what the CDC data actually mean:

https://www.forbes.com/sites/brucelee/2020/08/31/twitter-removes-claim-about-cdc-and-covid-19-coronavirus-deaths-that-trump-retweeted/#1f0bc6993178
[A lot of the tweets quoted have apparently been deleted, but I haven't found anything better for the explanations that remain]

 

Edit: OK, here's a blog by a KC Hospice and Palliative Care doctor who writes a lot of death certificates and can explain how it works:

https://drbartlettpear.com/2020/08/30/covid-19-series-entry-11/?fbclid=IwAR2ljMe3hLMr2GMG8DbfYcFhTgHvT0OfbVhsQ9a9VCvzH2mXufzgML8VroE

"you’ve probably figured out that a death certificate with ONLY the diagnosis of Sars-CoV-19 doesn’t even make sense. Jennifer didn’t go from perfectly healthy to dead from Covid-19 without SOMETHING HAPPENING in the interim. When people die from Covid-19, they die because the virus has caused something to go very wrong in their body. I would go so far as to argue that the doctors completing the death certificates on those 6% without any other factors listed were either 1) in a hurry, 2) lazy or 3) didn’t understand how to fill out a death certificate in the first place. I would be embarrassed to submit such a half-assed death certificate, personally!  

If you look at Chart #3 from the CDC (here’s the link again – you’re welcome), you will see that the conditions listed are a mishmash of both chronic and acute illnesses. Things like ARDS, pneumonia, respiratory arrest and cardiac arrest are all acute illnesses most likely CAUSED by Covid-19. Other conditions like chronic lower respiratory disease, hypertension, diabetes and Alzheimer’s are all more chronic conditions that could have been exacerbated by Covid-19 or predisposed to a poor outcome. I’ll let you peruse the chart for yourself.

 

OK, Original CDC Data:

https://www.cdc.gov/nchs/nvss/vsrr/covid_weekly/index.htm?fbclid=IwAR2-muRM3tB3uBdbTrmKwH1NdaBx6PpZo2kxotNwkUXlnbZXCwSRP2OmqsI#Comorbidities

 

Summary: having multiple causes of death, or pre-existing conditions, listed does not mean "you didn't die of covid-19". 

Said before, bears saying again: Hypertension (45%), heart disease (7.5%), diabetes (10%) , obesity (42%), and overweight taken together are conditions that affect a huge number of Americans.  It's not quite additive because many have more than one of these conditions, but it's very close to half of all Americans have a pre-existing condition linked to increased risk of serious disease from covid-19.