There’s a great article in Nature with graphics explaining immunity and how vaccines work. I think it was Gvg the other day who wanted more information.
I think the article is ungated. Let me know if it’s not available, and I’ll transfer the graphics here.
Open thread!
trollhattan
Thanks! Opens and displays fully for me. Can I add that “vesicle” is what I call a boat?
PenAndKey
I’m not surprised to see that protein antigen vaccines are the most common type being developed, but these graphics are all awesome. They’re the kind of thing I would absolutely loved when I was taking my introductory virology course in college. Hopefully they help clear up the confusion some people have.
One issue I’ve had since day one in these discussions is the concept that people who have recovered from the virus and actively have anti-SARS-CoV-2 antibodies in their bloodstream aren’t considered immune when discussing relapse risk. I fully understand that everyone’s trying to avoid giving grist to the idiot politicians who will try their “immunity passport” idea at the slightest provocation, but I was always taught that if a patient recovers from a viral infection and is presenting antibodies for the virus they more likely than not have developed at least partial immunity. Is the refusal to say so in this situation an abundance of caution scenario because laypeople have issues with nuance, or am I actually missing something?
polyorchnid octopunch
@PenAndKey: I think part of it is that a lot of the pols are being vague about the differences between partial/temporary immunity and permanent immunity. If it turns out that it’s like the flu where a person acquires immunity that runs out in half a year then from the POV of validation it’s pretty useless.
MattF
And, somewhat on topic, Derek Lowe reviews what we know now about the efficacy of remdesivir.
Also, some known facts about coronaviruses.
Cheryl Rofer
@PenAndKey:
I am not an expert in this, but I have been reading a lot, so let me give you my understanding. I think that the experts are cautious for a number of reasons.
Add to those uncertainties, the political desire to declare herd immunity achieved, and you can see why the experts are cautious in what they say.
I’ve been cautious on the subject too, for those reasons.
PenAndKey
That was my take as well, but I’ve been scolded repeatedly by people for using the word immunity so I figure everyone’s walking on eggshells right now. Which really irritates me, because as severe as this issue is I find it absolutely fascinating as a microbiologist and we had it drilled into our heads for years that vaccinations aren’t always a 100% fix even when they do exist. It’s like trying to discuss evolution with people that don’t understand the meaning of the word theory. They’re not wrong, necessarily, but we’re not speaking the same technical language.
/end rant
Searcher
@PenAndKey: Basically the “you get it and you’re immune” idea is like, mostly true, with a few caveats.
Sometimes your immune system begins over-reacting to subsequent exposures, making things worse the more your are exposed, (allergies and dengue fever); sometimes the pattern-matching your immune system does to recognize the virus ends up overly broad, and gets pruned after a few weeks or months because it keeps trying to kill your own cells (or worse, it doesn’t get pruned).
My understanding is that, Bayesian prior for this disease is that we expect a long-lasting immunity, but because it kills 1% of the people it infects and so many shitheads seem to be OK with that, a lot of science communicators are taking the opportunity to be very careful and not put the cart before the horse.
PenAndKey
That particular virus is absolutely fascinating. It’s not even a single virus, but 5 distinct serovars representing something like 50 strains that can all present the full disease symptoms. When someone recovers from one infection they’ll have the immunological memory for that infection. When they get a second infection from one of the other strains it can trigger an antibody-dependent enhancement reaction that interferes with the immune response the second time around. That can lead to general inability to fight it off or can even cause a cytokine storm response that absolutely ravages the patient. It’s… nasty.
So far while some mutations have been reported that doesn’t appear to be a major risk likelihood this time around because the main SARS-CoV-2 strain is just one strain, but it’s always something to keep a lookout for.
Mallard Filmore
@PenAndKey:
This virus, along with the ones for flu, had some mutated variants. The flu vaccine is really a SWAG from the experts selecting 2 or 3 flu variants for which you will get immunity.
This virus will mutate, which will degrade immunity. Also human bodies may “forget” how to fight it.
David C
Back in the previous millennium I worked on vaccines for HIV and Lyme disease – one a virus and one a spirochete. Failed. the short answer to Covid is that we don’t have a good handle on the natural history of the immune response – characteristics and longevity. It’s not influenza, so we can’t use that as an example, either.
For people who want to nerd out, the National Academy of Medicine has a good webinar – with about 6 minutes of music at the beginning that was not edited out. My old boss, Richard Hatchett of flatten the curve fame and head of CEPI, talks about vaccines around 1:16:55. And Tony Fauci’s featured – talking science.
http://www.nasonline.org/about-nas/events/annual-meeting/nas157/covid19-update.html
David C
@Mallard Filmore: All viruses mutate but the immune responses for some, like measles, cover the range of mutations well. We just don’t know if immunity will be less effective over time because of either mutations or a waning immunologic memory.
satby
Interesting, thanks Cheryl!
Gvg
Thank you. Sorry it took me awhile to find this