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Monday, April 27, 2020

Infection Rates, Immunity, Vaccines, Excess Mortality

Commenters Tom S and Bebe have provided some interesting links that go directly to some of the issues that I attempted to address yesterday.

Tom S sent a link to some tweets by Dr. David States, Chief Medical Officer of Angstrom Bio in Austin, TX (they have a great map at their site). The tweets are intended to address the matter of developing a vaccine against Covid19. Remember? That happened last week, or will happen next week, or maybe in 18 months. We'll get to that a bit later, but States touches on a number of matters that are important.

Rate of Transmission


First, I want to point out that he totally disagrees with my view or 'narrative' that Covid19 is less infectious or transmissible than the flu and therefore will not be spreading like wildfire across the fruited plain:

David States
@statesdj
Replying to @statesdj 
The problem is that SARSCOV2 is a highly contagious virus. While initial estimates for R0 were in the ~2.5 range, more recent estimates suggest it’s in the 3 to 5 range, and some individuals really do seem to be superspreaders shedding huge numbers of virus 5/ 
3:43 PM - Apr 21, 2020

David States
@statesdj
Replying to @statesdj 
That means a vaccine will need to be quite effective if it’s going to stop the spread of SARSCOV2. The polio, measles and smallpox vaccines are really remarkable medicines inducing high level long lasting immunity, but not all vaccines work so well 6/ 
3:43 PM - Apr 21, 2020

A Rate of Infection (RO) of 3-5 is very high for this sort of virus and would place SARSCOV2 at several times the RO of flu, which is known to spread widely through the population. And yet. Where is the evidence? The evidence that I'm aware of--and of course I have no comprehensive knowledge about this--seems to point in the opposite direction, based on antibody studies. Antibody studies in Italy have shown some significant hot spots, small mountain villages that are at 'herd' immunity levels--over 60%. However, for the general population in the north of Italy, one of the hardest hit areas in the world, levels are well below that, more comparable to those in the US. The Miami-Dade study that I cited yesterday came in at ~ 6%, and that was in a locality that was not rigorously locked down.

Overall, in a population with no immunity that was caught unawares, we would expect higher levels of infection if the virus really is that infectious. Again, the frequently repeated guideline--6 ft./10 minutes--would also seem to militate against such a high RO. As do the repeated statements by public health officials that most spread seems to occur in close circles, like families. One way or another, it doesn't appear that the virus is spreading like we had been told it would.

I may have to eat my words, but I'll wait a bit longer.


Immunity


Before we look at States's views on immunity, we need to look briefly at the link that Bebe sent on the same subject: What is antibody identification? For our purposes, all we need to know is in this paragraph:

The first time someone is exposed to a foreign substance, like a virus or bacterium, it may take the immune system up to two weeks to make an antibody blueprint and to produce enough of a specific antibody to fight the infection. This initial response consists primarily of IgM antibodies. Several weeks later, usually after the immediate threat has passed and the infection has resolved, the body creates IgG antibodies. It remembers the blueprint for fighting this microorganism and maintains a small supply of antibodies (a mixture of both IgM and IgG). The next time the body is exposed to the same foreign substance, it will respond much more strongly and quickly, to provide primarily IgG antibody protection.

Obviously this information goes also to the issue of 'herd' immunity. We're talking about a timeline of several weeks, at least, for the development of antibodies. That's why the Italian findings are important, since the infection arrived in Italy quite early on.

However, keep that distinction between IgM and IgG antibodies in mind, because that's what States addresses. And what he says goes very much against the notion that has been irresponsibly propagated that 'herd' immunity is a thing that happens more or less inevitably. In fact, "lots of people don't develop much of an IgM response," and much like antibodies produced against the common cold (a human - as opposed to a bat - coronavirus), IgG antibodies against SARSCOV2 fade after about 2 months:

David States
@statesdj 
There’s a nice preprint just out on antibody responses to SARSCOV2. Lots of people don’t develop much of an IgM response and the IgG response fades noticeably after just two months 2/ 

https://medrxiv.org/content/10.1101/2020.04.15.20066407v1.full.pdf
3:41 PM · Apr 21, 2020

And just to be sure you don't miss what he's saying, States rubs it in a bit:

David States
@statesdj
Replying to @statesdj 
This is consistent with the other human coronaviruses. They induce an immune response, but it tends to fade so the same virus can reinfect us a year or two later. 3/

Human Coronavirus: Host-Pathogen Interaction
Human coronavirus (HCoV) infection causes respiratory diseases with mild to severe outcomes. In the last 15 years, we have witnessed the emergence of two zoonotic, highly pathogenic HCoVs: severe... 
3:41 PM - Apr 21, 2020

That's distinctly bad news for those pinning their hopes on a rapid development of 'herd' immunity, with minimal mortality in the process.

Vaccines


States uses that information to make a prediction about vaccine development. We keep hearing people asking, Hey, scientists, roll out that vaccine already! Remember the HIV vaccine? The Ebola vaccine? No? Vaccines are by no means easy to develop, and in the case of coronaviruses I have read (sorry, nor ref.) that there has never been a vaccine developed for a coronavirus. Which explains why we don't get a vaccine for the common cold, which does, after all, lead to the deaths of many older people. So, in that context, and bearing in mind the fact the information about antibody development, States warns:

David States
@statesdj
If you’re hoping a vaccine is going to be a knight in shining armor saving the day, you may be in for a disappointment. SARSCOV2 is a highly contagious virus. A vaccine will need to induce durable high level immunity, but coronaviruses often don’t  induce that kind of immunity 1/
3:40 PM - Apr 21, 2020

So, if development of 'herd' immunity was Plan A, and development of a vaccine was Plan B, uh, maybe you need to be thinking about a Plan C. Hey, I've got that plan, but it's not scientifically endorsed.

Excess Mortality


Finally, there's the matter of excess mortality. In the US a lot of people claim that the government is inflating Covid19 mortality. In other countries, however, the claim is that mortality reporting is being deliberately depressed. For example, just last week I was reading a report from Sweden. There, for a death to be listed as due to Covid19 there must be an actual positive test result. Problem is, Sweden is testing at half the rate that the US is testing, and maybe a third or less the rate as the other Scandinavian countries. Doctors at Swedish nursing homes are complaining that they're being pressured to NOT do tests. But a comparison of year to year data shows that the raw mortality figures in Sweden in spiked beginning in March and have been running at 25-50% hire than a year ago. Hmmm.

So with these controversies going on, some smart aleck at the Financial Times came up with the bright idea of running a comparison of mortality numbers for lots of countries, using a basket of previous years and comparing that basket to what's currently going on, death wise. The conclusions are summarized at Zerohedge: Coronavirus Deaths Likely 60% Higher Than Official Numbers Reflect, FT Finds. The claim is that deaths have been underreported to the tune of 122K dead people not counted as Covid19 fatalities. The only country not to show this sort of reporting discrepancy was Denmark:

The death toll from coronavirus may be almost 60 per cent higher than reported in official counts, according to an FT analysis of overall fatalities during the pandemic in 14 countries. Mortality statistics show 122,000 deaths in excess of normal levels across these locations, considerably higher than the 77,000 official Covid-19 deaths reported for the same places and time periods. If the same level of underreporting observed in these countries was happening worldwide, the global Covid-19 death toll would rise from the current official total of 201,000 to as high as 318,000.

There's lots more at the link, but here are two graphs to give an idea of what's happening:




Notice that the US isn't included. But there's a second graph that includes NYC--which is a total disaster compared to basically everywhere else in the US:




In light of this, it's worth quoting from the conclusion at Zerohedge, if for no other reason than to show how optimistic my "narrative" actually is:

Bloomberg on Sunday reported that the number of severe respiratory infections reported in Mexico over the past two months, coinciding with the end of flu season, were up more than 50% compared with last year. Experts working for the Mexican government quietly told Bloomberg that the increase is likely 100% attributable to the virus. 
... 
To be sure, the FT doesn't question the general trends displayed in global data - well, at least not in developed countries like the US and Italy. But it's just the latest reminder that armchair experts claiming that the true mortality rate for the virus is actually a small fraction of a percent are likely also gravely underestimating the total number of deaths that have gone underreported.

This just means that the grainy videos released by brave Wuhanese during the early days of the outbreak remain the most reliable indicators of what the novel coronavirus is capable of if left unchecked. 
Though they've been wiped from the Chinese Internet, millions around the world witnessed the videos of dead bodies of the elderly in the streets, hospital hallways packed with the doomed, pandemonium, chaos - and Party officials firing up the crematorium out back.

6 comments:

  1. From Aesop
    The r-naught for seasonal flu is about 1.3.
    https://www.businessinsider.com/coronavirus-contagious-r-naught-average-patient-spread-2020-3

    The r-naught for SARS-CoV-19 is now assessed to be 5.7.
    Earlier estimates put it at 2.2-2.6, but they've been revised upwards.
    https://www.healthline.com/health/r-nought-reproduction-number

    From comment at:
    http://raconteurreport.blogspot.com/2020/04/about-those-studies.html?m=1

    ReplyDelete
    Replies
    1. Thanks for those links. Of course, seasonal flu R0 is influenced by vaccination and natural immunities built up over decades. Some interesting comments at RR--make me feel like not such a bad boy. :-) 'Unethical' now seems almost mild. Saw your comment, too bad no responses. Based on the description of how R0 was arrived at I better not recant too soon.

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  2. If we are all in lockdown, where are the new infections coming from?

    My guess is a lot from nursing homes. Especially with the ny, nj, and Ca required to admit covid patients.

    A video at CT explains the high death rate in NYC.

    I believe masks will decrease the r factor significantly. Czech Republic had amazing results. And it’s helping in LA and Riverside Counties in CA.

    I don’t get the politics of prolonging a shutdown.

    ReplyDelete
    Replies
    1. Thanks Ray, I sincerely hope all this is wrong about RO. I really wanted grounds for optimism. I'd appreciate a link to that video. I've been writing so far this morning, and now I need to take my walk (without a mask) and catch up on news. But I'll get to your links.

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  3. CT video from a nurse practitioner on NYC:
    https://theconservativetreehouse.com/2020/04/26/an-alarming-message-about-healthcare-and-covid-19-in-new-york-city/

    Reminds me of "Killer King" - Hospital set up in LA after the Watts riots that had a high death rate. Only way it got fixed was by shutting it down... This could also explain the high death rate of certain minorities, if the hospitals in their area are basically killing people due to horrible care.

    And with the Subway Mess, I don't see NYC getting better till they get herd immunity:
    https://nypost.com/2020/04/25/passed-out-passengers-trash-fill-subway-cars-amid-coronavirus-crisis/

    More on NYC Nursing Home Debacle, or admitting CoronaVirus Positive Patients:
    https://nypost.com/2020/04/25/new-york-lacked-common-sense-in-nursing-homes-coronavirus-approach/

    And NY and CA had the same policy.
    You already linked to the Greenfield article already:
    https://www.frontpagemag.com/fpm/2020/04/1-5-coronavirus-deaths-could-have-been-prevented-daniel-greenfield/

    ReplyDelete
  4. Meanwhile another statistics genius rings in with this one at the Federalist;

    Why No COVID-19 Models Have Been Accurate, And How To Fix That

    "The decisions that are being made during this crisis are far too important and complex to be based on such imprecise data and with such unreliable results.”

    https://thefederalist.com/2020/04/27/why-no-covid-19-models-have-been-accurate-and-how-to-fix-that/

    The headline seemed so loaded with hubris that I had to read this article. I’ll keep my opinion to myself, deferring to others more qualified than I…

    ReplyDelete