Sunday, April 26, 2020

About Those Antibody Tests--And Immunity

So, instead of Buzzfeed or a blog, I turn now to Scientific American. Actually this relatively brief article appeared on April 10. It explains succinctly what the limits to these tests are and no one should be relying on them for much of anything, in terms of policy recommendations. 

What Immunity to COVID-19 Really Means 
The presence of antibodies to the SARS-CoV-2 virus could provide some protection, but scientists need more data
Unlike diagnostic tests, which are used to confirm the presence and sometimes load, or amount, of the virus, antibody tests help determine whether or not someone was previously infected—even if that person never showed symptoms. Widespread use of such assays could give scientists greater insight into how deadly the virus is and how widely it has spread throughout the population. 
It is less clear what those antibody tests mean for real life, however, because immunity functions on a continuum. With some pathogens, such as the varicella-zoster virus (which causes chicken pox), infection confers near-universal, long-lasting resistance. Natural infection with Clostridium tetani, the bacterium that causes tetanus, on the other hand, offers no protection—and even people getting vaccinated for it require regular booster shots. On the extreme end of this spectrum, individuals infected with HIV often have large amounts of antibodies that do nothing to prevent or clear the disease. 
At this early stage of understanding the new coronavirus, it is unclear where COVID-19 falls on the immunity spectrum. Although most people with SARS-CoV-2 seem to produce antibodies, “we simply don’t know yet what it takes to be effectively protected from this infection,” says Dawn Bowdish, a professor of pathology and molecular medicine and Canada Research Chair in Aging and Immunity at McMaster University in Ontario. Researchers are scrambling to answer two questions: How long do SARS-CoV-2 antibodies stick around? And do they protect against reinfection? 
Early on, some people—most notably U.K. Prime Minister Boris Johnson (who has the virus and is currently in intensive care) and his government’s scientific adviser Patrick Vallance—touted hopes that herd immunity could be an eventual means for ending the pandemic. And although it appears that recovered COVID-19 patients have antibodies for at least two weeks, long-term data are still lacking. So many scientists are looking to other coronaviruses for answers.

So, the bottom line is ... that there really isn't a bottom line right now. All that shouting about 'herd' immunity? Perhaps this article helps explain why so many public health people were warning against that as a 'policy.' With a 'novel' virus it's more of a crap shoot. There's a reason why there's no vaccine for the common cold.


  1. And this is the short answer for why a vaccine 18 months from now is less than a crap shoot:

    Remember Ebola? First surfaced circa 1967. First reliable/acceptable vaccine tested last year, in the field, trying to quell the worst outbreak so far. First human trials done by vaccinating 1st line health workers on the fly in hope it would work well enough to allow containment, still a question mark. That's 50+ years of research and still a 'Hail Mary'.
    Tom S.

    1. Sure. And I recall Osterholm, when asked about a vaccine, said: Remember, I'm the guy who said there'd be no HIV vaccine in my working lifetime. So when you hear these people yammering about immunity and vaccines ... You have to take it with a grain of salt. It's not impossible, but not nearly as likely as they seem to think. So when you talk about public policy responses to a novel virus, this too is something to consider.

    2. Tom, I just got done reading that. Very interesting, and it contradicts my "narrative" in important respects. He states as fact that the SARS-CoV-2 is much more contagious than flu, and also not conducive to developing immunity. That's significant bad news. It also explains the confidence of establishment epidemiologists that this will not be a short term problem.

      OTOH, if it's as infectious as he says, how is it that it hasn't spread like wildfire.

    3. My theory: It has spread like wildfire, but we have no way to prove or disprove that.
      I believe I have COVID19. And I don't care. Nothing I can do. I'm 61 years old and dealing with it.

      Will I go to the doctor for a test? No. Not unless they simply hand me a supply of HCQ/Zinc. Otherwise I know a doctor visit will do me absolutely no good.
      I'm sure many millions of people feel the same.

      Why do I think I have COVID19?
      1 - My girlfriend is a paralegal working with Chinese immigrants to Los Angeles.
      2 - the flu-like symptoms I get every year lasted the normal 2 or 3 weeks back in December, but unusal fatigue has lingered 4 months.
      3 - last week after an excercise session I showered and collapsed on the couch with bone-deep fatigue I haven't felt since I had mononucleosis 55 years ago.

      Something more than the normal ageing process is going on. Whatever. Life happens. There's no hiding from it or COVID19.
      Let's get on with life, can we, please?

    4. My advice--find a doctor you trust.

  2. I presented that link because it describes the reality of vaccine development in general, and against 'novel' pathogens in particular, very clearly and succinctly. For instance, how can you make a vaccine against a pathogen that the immune system can't recognize.

    As to his comments about transmission I can't say. I ascribe that as much to the vast sea of anecdotal, erroneous, and even half baked data floating around, so much so that even medical professionals have difficulty separating the wheat from the chaff on a day to day basis. For instance, why are some doctors insisting that hydroxychloroquine is of no use when when their waiting to administer it until the patient is in ICU when every successful use of it that I have read about was as soon as possible after diagnosis. To much data: not enough definitive information, so they try to over think it and play it safe.
    Just a guess, but human nature is as much a factor here as in any other endeavor.
    Tom S.

    1. No doubt, re human nature. It happens in "science" all the time.

      The novel features of the virus are very worrisome.

    2. To demonstrate what I am talking about 'Lancet' alone has published 450+ articles about the virus since Jan 24, 2020, a mere 93 days.
      No person can possibly digest that amount of info on a daily basis, not to mention literally hundreds of other publications/sources and especially while actually treating patients at the same time. Is there a large, specifically organized and dedicated team somewhere sorting, collating, and synthesizing all this 'chatter' in such a way that those in the trenches can get reliable, useful and timely intel on the enemy? If so they're failing miserably. If not then fire, demote, or just transfer to 'Anthrax Island' a couple of thousand sinecured medical policy wonks and hire (or outright draft) a few thousand grad students of immunology, pathology or epidemiology (people that can digest medical writing) and get something resembling Bletchley Park up and running. Too many people in Washington are involved in managing the crisis rather than repelling the attack.
      Tom S.

  3. Aside from acquired immunity and ease of contagion, I would like to know if this is a bio-engineered virus. If it is, how was it engineered, who engineered it and why. Accidental release from a lab in China is a possibility, as is intentional spread - why was Wuhan locked down for travel in country, but not for international flights?
    Yeah, I know , it sounds conspiratorial, however China appears to be on it's way to coming out of this smelling like a rose. I'm smelling a rat.

    1. It is the Year of the Rat. In fact the bio-engineering of bat viruses, supposedly with regard to developing vaccines, has been going on at the Wuhan lab for about 10 years. The lead biologist there had cooperated in gain-of-function engineering with a US scientist in NC. The US was funding some of that Wuhan research. It seems the most probable explanation.