Mild COVID-19 induces lasting antibody protection, study finds: People who have had mild illness develop antibody-producing cells that can last lifetime -- ScienceDaily
Category: News & Politics
Via: vic-eldred • 3 years ago • 34 commentsBy: Ali Ellebedy, PhD (ScienceDaily)
S E E D E D C O N T E N T
Months after recovering from mild cases of COVID-19, people still have immune cells in their body pumping out antibodies against the virus that causes COVID-19, according to a study from researchers at Washington University School of Medicine in St. Louis. Such cells could persist for a lifetime, churning out antibodies all the while.
The findings, published May 24 in the journal Nature, suggest that mild cases of COVID-19 leave those infected with lasting antibody protection and that repeated bouts of illness are likely to be uncommon.
"Last fall, there were reports that antibodies wane quickly after infection with the virus that causes COVID-19, and mainstream media interpreted that to mean that immunity was not long-lived," said senior author Ali Ellebedy, PhD, an associate professor of pathology & immunology, of medicine and of molecular microbiology. "But that's a misinterpretation of the data. It's normal for antibody levels to go down after acute infection, but they don't go down to zero; they plateau. Here, we found antibody-producing cells in people 11 months after first symptoms. These cells will live and produce antibodies for the rest of people's lives. That's strong evidence for long-lasting immunity."
During a viral infection, antibody-producing immune cells rapidly multiply and circulate in the blood, driving antibody levels sky-high. Once the infection is resolved, most such cells die off, and blood antibody levels drop. A small population of antibody-producing cells, called long-lived plasma cells, migrate to the bone marrow and settle in, where they continually secrete low levels of antibodies into the bloodstream to help guard against another encounter with the virus.
The key to figuring out whether COVID-19 leads to long-lasting antibody protection, Ellebedy realized, lies in the bone marrow. To find out whether those who have recovered from mild cases of COVID-19 harbor long-lived plasma cells that produce antibodies specifically targeted to SARS-CoV-2, the virus that causes COVID-19, Ellebedy teamed up with co-author Iskra Pusic, MD, an associate professor of medicine. Ellebedy already was working with co-authors Rachel Presti, MD, PhD, an associate professor of medicine, and Jane O'Halloran, MD, PhD, an assistant professor of medicine, on a project to track antibody levels in blood samples from COVID-19 survivors.
The team already had enrolled 77 participants who were giving blood samples at three-month intervals starting about a month after initial infection. Most participants had had mild cases of COVID-19; only six had been hospitalized.
With Pusic's help, Ellebedy and colleagues obtained bone marrow from 18 of the participants seven or eight months after their initial infections. Five of them came back four months later and provided a second bone marrow sample. For comparison, the scientists also obtained bone marrow from 11 people who had never had COVID-19.
As expected, antibody levels in the blood of the COVID-19 participants dropped quickly in the first few months after infection and then mostly leveled off, with some antibodies detectable even 11 months after infection. Further, 15 of the 19 bone marrow samples from people who had had COVID-19 contained antibody-producing cells specifically targeting the virus that causes COVID-19. Such cells could still be found four months later in the five people who came back to provide a second bone-marrow sample. None of the 11 people who had never had COVID-19 had such antibody-producing cells in their bone marrow.
"People with mild cases of COVID-19 clear the virus from their bodies two to three weeks after infection, so there would be no virus driving an active immune response seven or 11 months after infection," Ellebedy said. "These cells are not dividing. They are quiescent, just sitting in the bone marrow and secreting antibodies. They have been doing that ever since the infection resolved, and they will continue doing that indefinitely."
People who were infected and never had symptoms also may be left with long-lasting immunity, the researchers speculated. But it's yet to be investigated whether those who endured more severe infection would be protected against a future bout of disease, they said.
"It could go either way," said first author Jackson Turner, PhD, an instructor in pathology & immunology. "Inflammation plays a major role in severe COVID-19, and too much inflammation can lead to defective immune responses. But on the other hand, the reason why people get really sick is often because they have a lot of virus in their bodies, and having a lot of virus around can lead to a good immune response. So it's not clear. We need to replicate the study in people with moderate to severe infections to understand whether they are likely to be protected from reinfection."
Ellebedy and colleagues now are studying whether vaccination also induces long-lived antibody-producing cells.
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It's official - what most rational human beings suspected.
So do we believe the Science or the bureaucrats?
On that note, there was this farce:
While encouraging, the results from bone marrow samples for 18 people does not meet statistical relevance. That and the study would need to be duplicated by a second independent study.
Again, encouraging, but I would suggest holding fire in either direction until a larger body of data is accumulated.
How bizarre! You mean to tell me a person catches a virus, mounts an effective immune response and is then protected from future infection for a long time? Who ever heard of such a thing?
/s duh
I would still rather not get it to begin with.
So what is the significance of this seed?
After all, this is how science works. Time must pass so that measurements can be taken and compared and then that data is used to formulate an understanding.
To wit, what else would anyone expect the scientific community do other then secure findings and report on same?
And prior to the actual data does anyone expect the scientific community to do anything other than make their best educated guesses?
To bash science and/or scientists?
You mean using them.
The left is doing to science what it did to history.
So basically you seeded this to give yourself a (shaky) platform to bash the political left.
So it's not science you're really interested in. It politics. Or more accurately, political bashing. Seems rather dishonest to me.
Bingo!
In a word, yes.
Telling the truth, excellent.
You think the seed does that? Which part of it? Just seems like a report about a study. Pretty neutral.
Read the seeder's comments.
The SEED doesn't.
It's not the seed itself that I was referring to.
I’m not seeing the bashing of science or scientists, but even if someone were, so what? Articles get seeded and people have a take on it. Criticism is not necessarily “bashing.” Anyway, counter it with an argument if you’re so inclined.
I personally think there has been a lot of unnecessary confusion in communication about the virus, antibodies, and vaccines, as if established concepts surrounding the interconnectedness of those things was brand new to everyone. I think there has been extreme equivocation in the coverage - beyond what is warranted - and emphasis on rare cases that far outweighs their significance.
For example, millions of people (at least 169 million, so far) have been infected by the virus, but once in a while, you hear about someone who got sick a second time after apparently recovering completely. The reporting and guidance that evolves out of these second infections treats these events as if they were common, and suggest that it’s a total mystery as to whether or not most people are protected by their own antibodies. But the truth is, second infections are not common (the numbers by country tend to be 50, 100, or 200 out of many thousands), they tend to be milder, and we know very well how antibodies work.
The bottom line is the findings reported in the seed are not surprising, but you wouldn’t know that to listen to some of the hysterical reporting on the matter.
The findings are certainly what one would expect. Is there someone worthy of respect (i.e. one we should take seriously) who is hysterically reporting on these findings?
Are you really ignoring the importance of the mask to the left?
What? This seed is about plateaued levels of antibodies and the sometimes slow but deliberate progress of scientific knowledge. It did not and I did not even mention masks.
There is plenty of data and studies to support mask wearing. Some of the best came from a study in Kansas not more than a year ago...
As a second general point to support wearing masks..... where did cold and flu season go last year. Answer: We didn't have one.
Maybe I'm mistaken but didn't you say a little while ago that you still wear a mask in public ?
This is what happens when the world is viewed almost exclusively through a partisan lens.
The following is not directed at you, of course, as I'm sure you already know this.
This study tells us that of an extremely small sample of people who had Covid-19, 79% had plasma cells in their bone marrow that produce antibodies to the novel coronavirus. That's great, but it is not conclusive, due to the aforementioned sample size and the fact that only 5 of the previous participants followed up to provide second bone marrow samples, rendering the sample size even smaller.
Scientists are by nature conservative in their interpretation of data. No scientist worth his or her salt would say that this one study means that infection with Covid confers long-term or lifelong immunity. They would say it indicates as much, but would require further evidence to make such a declaration.
Also, such immunity may or may not be effective against future strains of coronavirus.
As far as masks and "the left", Virginia's Democratic governor rescinded mask mandates as of today, as well as capacity and distancing restrictions. He did so based on CDC recommendations, our high rate of vaccination, and our decreasing rate of infections and hospitalizations - in other words, based on the science.
I will add that the number of people infected with COVID-19 are a tiny minority of the population (about 10%). So even if getting COVID-19 makes one immune, that does nothing to establish herd-immunity with a result of keeping COVID-19 under control. Vaccines are key and prior to vaccination precautions are essential.
Excellent addition.
Apparently you missed it-- but the article is about the Vaccine-- not about masks!
Squirrel
It’s just a summary of a report published in Nature. It doesn’t seem to have any purpose beyond that.
To me this seed is a good report of progress on our understanding of COVID-19 and its effect on the human body. It is what one would expect, but biochemistry does not always conform to our intuition.
Seems pointless to use this update report to spin a (weak) partisan attack.
Bingo!
I guess I missed the partisan part.
I think discussion of the virus generally has been itself infected with a lot of confusion, but I don’t think that’s partisan. There is plenty of it to go around.
For example ...
Indeed you did.
So I copied the exact remark and am posting it here ...for your viewing pleasure!
Enjoy:
Are you really ignoring the importance of the mask to the left?
To the Left...hmmm... I wonder what that means? Obviously not political...is it?
/sarc