Question about a worrying article re: vaccine-produced Covid antibodies

January 9, 2021 9:01 AM

In this article by Dr. William Haseltine, "The Moderna Vaccine’s Antibodies May Not Last As Long As We Hoped"

he analyzes a study of 34 people who were given the Moderna vaccine: "The NEJM study followed a group of 34 patients who had taken both doses of mRNA-1273 and analyzed their antibody counts from the administration of the first dose for 119 days. Neutralizing antibodies were monitored in subgroups of 18-55 years of age, 56-70, and 71+, as shown below."

In short, they found that, in the older groups, neutralizing antibodies dropped a LOT in the 119 days (they hardly dropped at all in the younger group). So, I'm 70 years old, and my husband is 75. We happily received our first shots of the Moderna vaccine a couple of days ago. So now I'm worrying about how long immunity is going to last in our (older) population, the population that's most at risk of severe Covid disease.

Here's my specific question, though: Haseltine says that "A significant determinant of vaccines’ effectiveness in controlling a pandemic is antibody duration—how long the antibodies last in a person’s system." But this reminds me of how, when the first reports of immunity after Covid infection (not vaccination), came out, initially they were saying things like, "Oh my god, after a couple of months, Covid survivors don't have antibodies anymore! So immunity after Covid infection is horribly short-lived! We are doomed!"

However, later, articles starting coming out saying things like, "Wait! It's NORMAL that antibodies don't last long after an infection. They're not supposed to! The really important thing is that there is T- cell and B-cell immunity, and it looks as if those may last a much longer time, maybe even years!"

So -- is immunity after Vaccination very different from immunity after Infection? Does your body produce T- and B-cell immunity after infection, but, if you're trying to derive immunity from vaccination, it does NOT? Is it only antibody immunity that a vaccine provides, so that, if you don't have measurable antibodies a few months after vaccination, you're screwed?

(side note: I always find that, while Fauci tends to shine an optimistic light on things, Haseltine is like, Dr. Debbie Downer. Anyone else feel that way? I want to follow the Light of Fauci, but my personality always brings me back to Haseltine's Eeyore point of view. How does one sort through all of this??)

(oh, and I know the ultimate answer is: We Don't Know Yet -- obviously, But I am hoping for a little more information and insight than that right now, if possible.)

posted by DMelanogaster to Science & Nature (5 answers total)

Epidemiologist and vaccine wonk chiming in to remind everyone that popular science reporting is, um, generally not very thorough (and I'm being very diplomatic). So, for the record, circulating neutralizing antibodies are not and should not be treated as the sole measure of the capacity for a human immune system to mount an effective immune response. We've known this for a very long time. It is "expensive" for your body to constantly churn out antibodies to protect against a threat that may only occasionally show up. This is why antibody titers decline over time, without fail. There are immune cells that persist much, much longer than free-floating serum antibodies and serve as the immune system's memory. Once the invader returns, if these cells effectively recognize it they send out the signal to start churning out those expensive antibodies again. It remains to be seen how strong this memory is for Covid-19, but that this is the case is like immunology 101 and it's a sign of the times that this Forbes piece doesn't make a single mention of it.

I will step off of my soapbox while nevertheless encouraging everyone to get whatever vaccine is available to you as soon as possible.
posted by late afternoon dreaming hotel at 9:42 AM on January 9, 2021 [57 favorites]

Response by poster: well, I did more research and it seems that the Pfizer vaccine stimulates more T-cell response than the Moderna vaccine, and that was why Dr. Haseltine singled out this Moderna study

Link to study

Oh well. I couldn't choose what vaccine I got.
posted by DMelanogaster at 9:51 AM on January 9, 2021

Best answer: Also remember even if your immunity goes down over time, your chances of contracting the disease go down dramatically if, you know, you're not exposed to the disease. Like most Americans of my generation, I was never vaccinated for smallpox and therefore I would probably get it if I were exposed! But I don't get exposed because of earlier vaccination efforts. I don't think anyone thinks we're going to eliminate SARS-CoV-2 the way we've eliminated smallpox, but if we get community spread down, everyone is protected, even those whose immune response is not strong.

I used to teach an evidence-based medicine class, and one framework that EBM follows is using POEM: patient-oriented evidence that matters. Basically evidence is only useful if it allows you to make a meaningful decision about patient care (your own care in this case). It's almost definitely in your interest to get vaccinated with the first vaccine available to you regardless of the longterm differences in the vaccines, and it's highly unlikely that you would have been able to choose which vaccine to get. Plus you already got it! So although this evidence is interesting, it doesn't "matter" for your purposes, or for most people's right now, since we largely won't get a choice in which vaccine we get.

Also it's entirely possible that you'll be able to get boosted with another vaccine later if it looks like that's indicated for your age group.
posted by mskyle at 9:56 AM on January 9, 2021 [16 favorites]

Best answer: For reference, I'm referring to memory B cells moreso than T cells. The bottom line here is nevertheless, these vaccines are great, even if we end up needing annual or periodic boosters. These studies are good and very necessary in academic and clinical improvement senses, and yet these studies shouldn't influence our collective interest in receiving any of the approved vaccines. Also, keep in mind that many, many, many more vaccines are in the pipeline. We've never had a situation where so many vaccines have been in development for the same illness at a given time. By orders of magnitude. In my field, this push to develop effective vaccines safely and quickly is recognized as an honest to goodness paradigm shift. Things are bad, no doubt, but the rewards of this crisis will pay dividends for years to come. Hang in there, everybody.
posted by late afternoon dreaming hotel at 10:29 AM on January 9, 2021 [23 favorites]

This WheatNOil Twitter thread does a good job of explaining how mRNA immunity works.
posted by Lanark at 1:37 PM on January 9, 2021