COVID Booster Shots - Thoughts/News?

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In summary: Pfizer released data on Covid-19 efficacy that falls off after four to six months in people who received the vaccine. The efficacy falls to 83.7% after four to six months. This is a concern because it means the vaccine is no longer effective. This falls in line with a recent study that found that immunity dropped to 83.7% after four to six months in people who received the vaccine. This is a concerning trend because it means the vaccine is no longer effective.
  • #1
kyphysics
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Anyone have research on whether it's necessary and/or a good idea to get one? Pfizer has said it's vaccine efficacy drops to 83.7% after 4 to 6 months. https://www.marketwatch.com/story/p...ng-the-company-case-for-a-booster-11627579817

It's already past 4-6 months for a lot of early vaxxers (some in the U.S. started in December and presumably got their 2nd dose in January) and with the surge of Delta here in the U.S., does that not seem very worrisome?

I also saw a story of people mixing and matching additional shots: https://www.cnbc.com/2021/07/26/del...vid-vaccines-over-concerns-about-variant.html

Some Americans say they are finding ways to get additional doses of the Covid vaccines, with some even going as far as receiving the extra shots from different companies. The thought is that by “mixing and matching” vaccines that use different platforms, people may be able to get broader protection against the coronavirus and its new variants. J&J’s vaccine uses an adenovirus, while Pfizer’s and Moderna’s two-dose vaccines use mRNA technology. It highlights the growing anxiety many Americans have over variants, including delta, already the dominant form of the disease in the U.S.
Has anyone tried to get an additional shot from a different company for possible "extra" protection?
 
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  • #2
kyphysics said:
It's already past 4-6 months for a lot of early vaxxers (some in the U.S. started in December and presumably got their 2nd dose in January) and with the surge of Delta here in the U.S., does that not seem very worrisome?
We haven't heard any announcement about a booster shot yet, only that Pfizer is planning to produce a booster vaccine (with adjustments?). I presume Moderna, AZ, and JNJ will do the same.

kyphysics said:
Has anyone tried to get an additional shot from a different company for possible "extra" protection?
I was thinking about that. My wife is five months from her second vaccine and I'm three months. Ostensibly, sometime in the Fall (Autuumn) time frame, we expect there will be an announcement for a third vaccination shot - September/October(?).
 
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  • #3
Most of the world can't get enough/any vaccine. Aside from the moral question of over consumption of scarce resources, which Americans are experts at, it may be in our own selfish interest to get the rest of the world vaccinated ASAP to end the pandemic. This is how we can reduce the risk of more dangerous variants, and how you can avoid asking if it's time yet for your 4th or 5th booster shot. OTOH, you're just one person, and if you can get a booster, and you want it, why not.

Maybe yet another variant on the prisoner's dilemma, sort of combined with the "My vote doesn't count because it's only one out of millions that will be cast."
 
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  • #4
kyphysics said:
It's already past 4-6 months for a lot of early vaxxers (some in the U.S. started in December and presumably got their 2nd dose in January) and with the surge of Delta here in the U.S., does that not seem very worrisome?
Here is the six month update from Pfizer.
.
https://www.medrxiv.org/content/10.1101/2021.07.28.21261159v1.full-text

In particular see fig 3. I don't see anything terrifying.
 
  • #6
DaveE said:
Most of the world can't get enough/any vaccine. Aside from the moral question of over consumption of scarce resources, which Americans are experts at, it may be in our own selfish interest to get the rest of the world vaccinated ASAP to end the pandemic. This is how we can reduce the risk of more dangerous variants, and how you can avoid asking if it's time yet for your 4th or 5th booster shot. OTOH, you're just one person, and if you can get a booster, and you want it, why not.
I guess that's a separate question/issue for me, but I agree that getting the rest of the world vaccinated is very important. I'm just very curious how current vaccines hold up and their level of degradation over time (e.g., how much protection might a fully vaxed person have 8...9...12 months later?).

But, again, I totally agree getting the world vaxed is a key to this. I always worry about a new mutation that evades vaccines and as long as everyone else is not vaxed, then the virus has more chances to do that.

Delta is just so darn transmissible too. It's R0 is 5-8, whereas the original Wuhan virus was statistically only infecting 2.5 people and the European first wave was "only" 3.
 
  • #7
That (pre-print) study defined efficacy as "Study endpoints reported here are vaccine efficacy (VE) against laboratory-confirmed COVID-19". So they are measuring confirmed infection not the original vaccine goals of hospitalization or severe disease reduction. Based on the original "severe disease" target the vaccines are essentially 100% effective. There are virtually no vaccines that prevent infection (HPV is one outlier), so IMO, having been vaccinated, all evidence is that COVID-19 is less of a personal threat than many other infectious diseases; flu, for example. We (the vaccinated) still need to be careful not to spread an asymptomatic infection to the idiots and the unfortunate that aren't yet vaccinated.

The personal reason to get vaccinated is to prevent severe disease, the societal reason is to reduce transmission. We are still waiting for good study data that shows that vaccination reduces transmission, but everyone thinks it does, and there are both good mechanistic reasons and related data to indicate that it does.
 
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E7kQlwDWQAkJ4z8?format=jpg&name=large.jpg

Here's the comparison for Delta, btw.
 
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Does anyone know exactly how much is a price of a vaccine shot? Who pays?
(Yes, I know it is free for the us. But somewhere, somebody is reimbursing the vaccine producer, it is the amount of that reimbursement and (if known) who does the reimbursement that I want to know)
 
  • #10
I could be wrong, but I feel like the U.S. has a greater percentage of "never vax" people than other countries.

There, sadly, may be a high limit to our vax holdouts (of those eligible, 57% are fully vaxed) and that's going to suck going forward.

I haven't given up hope, as some are converting, but you do have a lot of people who seem like they're just unwilling to listen. That unvaxed crowd here just gives the virus more chances to spread and mutate endlessly, no?
 
  • #11
kyphysics said:
It's R0 is 5-8, whereas the original Wuhan virus was statistically only infecting 2.5 people.
Citation please. Ro is nearly impossible to measure or model once society starts to implement non-pharmaceutical control measures. The spread of a virus in the population has as much or more to do with human behavior as with the intrinsic virial properties. Also in-vitro lab data (which is hard to do in BSL-3), while informative, isn't a great model for transmission in real world humans. Animal models are also problematic; ferrets and hamsters in cages aren't the same as people shopping at the store.

The Delta variant is more fit (not necessarily the same as more transmissible) in the population than previous versions, that is why it is spreading. But it turns out in population studies based on exponential spread, a very small increase in fitness, for anyone of many reasons, will cause that variant to overwhelm the population. That sort of epidemiologic data doesn't mean that we wouldn't have had similar case loads with the original or alpha variants alone. The fact that a variant is overtaking the population percentage doesn't necessarily imply that it is much more dangerous. In fact the case fatality rates are dropping, not rising (most likely due to better treatment). There is good evidence that the delta variant is more resistant to some of the monoclonal antibody meds, but otherwise it doesn't seem too much different in terms of severity.

The media hype about the delta variant obscures the fact that SARS-CoV-2 of any flavor is bad, and it's increased spread in the community can be primarily attributed to human behavior. OTOH, without the media scaring people about the delta variant, they'd probably be even more cavalier.
 
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  • #12
DaveE said:
Citation please.
I was using the BBC graphic above (see image).
 
  • #13
kaiatiuw said:
Does anyone know exactly how much is a price of a vaccine shot? Who pays?
(Yes, I know it is free for the us. But somewhere, somebody is reimbursing the vaccine producer, it is the amount of that reimbursement and (if known) who does the reimbursement that I want to know)
1) The government pays, using taxes and debt increase.

2) Have you heard of google search yet? I find it quite useful myself. Here's the 2nd search result for "COVID vaccine cost" https://www.managedhealthcareexecutive.com/view/the-price-tags-on-the-covid-19-vaccines
 
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  • #14
Thank you, exactly what I wanted to know.
 
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  • #15
Hi, kyphysics!

Headlines at "El Pais" (www.elpais.com): Will this be the fifth and final wave? Experts predict new rises in the curve, but less intense and virulent; The (Spanish) Ministry of Health does not give permission for human trials of a Spanish vaccine.
My personal opinion: I'm pessimistic. I think this virus is here to stay

Love, greetings
 
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  • #16
mcastillo356 said:
Hi, kyphysics!

Headlines at "El Pais" (www.elpais.com): Will this be the fifth and final wave? Experts predict new rises in the curve, but less intense and virulent;
I hope, mcastillo356!

I also hope vaccine efficacy does not drop off precipitously before people can either get a booster dose and/or the Delta surges stop/slow down a lot.
 
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  • #17


Recent piece (July 30, 2021) by Laurie Garrett, Pulitzer Prize winning science journalist and former UC Berkeley Ph.D. student in Immunology:
https://foreignpolicy.com/2021/07/30/booster-shot-coronavirus-covid-science/
The Science Says Everyone Needs a COVID-19 Booster Shot—and Soon
The biology of the delta variant has made mass revaccination an urgent necessity.
Very interesting analysis! *must read*
 
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  • #18
Some key text from Garrett:
A multinational study of six months’ use of two-dose Pfizer vaccine also found that efficacy wanes with time, from about 97 percent to a low of 86 percent—still robust. But none of the work involved delta variant exposure. A recent study in Scotland showed that both the AstraZeneca and Pfizer vaccines were considerably less able to prevent delta infection, compared with the alpha strain or original 2020 forms of the coronavirus. (No similar data has been published for the nearly identical Moderna vaccine, but most vaccine experts assume that what holds for Pfizer is also true for Moderna.). . .

In other words, the two-dose vaccinated individuals may have primed immune systems that can make neutralizing antibodies against SARS-CoV-2, but the enemy is coming at them in such massive numbers, and surging inside their bodies so rapidly, that some six to eight months after completing vaccinations, they may be unable to muster adequate defenses to prevent illness, even long-haul COVID-19. . .

All this is why Israel is starting a third round of national vaccination and why Pfizer wants the CDC and FDA to approve the same for the United States. According to data Pfizer presented to stock shareholders recently, the company estimated that a third booster shot had the potential to increase neutralization of the delta variant by up to a hundredfold, compared with before the third dose. [***}

It also appears that the United States may have blundered by setting the time interval between the first two doses at 21 days—a decision made by the CDC and FDA under the Trump administration. For reasons having less to do with science than with the rush to get as many British at least partially protected as rapidly as possible, Boris Johnson’s government chose a far longer time interval between doses—months. And that may explain why the delta variant’s dire impact seems to be reversing in the U.K., with daily incidence of new cases dropping rapidly. Plotkin, the vaccine inventor, says longer times between jabs—perhaps six months—give the immune system time to settle into its lulled memory status before getting another jolt of fake infection (which, after all, is what a vaccine is), prompting the manufacture of neutralizing antibodies. That length-of-interval issue has arisen with other vaccines, he says, consistently showing months, not days, are required between doses.

***It's possible Pfizer has financial incentives behind such an estimate, of course, but it's still a very big statement.
 
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  • #19
https://www.cnbc.com/2021/08/12/cdc...e-booster-shots-for-vulnerable-americans.html

CDC panel prepares to vote on Covid vaccine booster shots for vulnerable Americans

The CDC’s Advisory Committee on Immunization Practices is scheduled to meet Friday to consider Covid booster shots for such people, including cancer and HIV patients. On Thursday, the CDC updated its website to reflect that there is now a vote scheduled for the meeting around 1 p.m. ET Friday.

The Food and Drug Administration is expected to authorize on Thursday a third Covid vaccine shot for immunosuppressed populations, a highly anticipated move intended to shield some of the most vulnerable Americans from the highly contagious delta variant.

The FDA OK is not the final go-ahead, however. The CDC advisory committee must then issue a recommendation to distribute the booster shots. If the CDC accepts the advisory group’s recommendation, as expected, then third shots could begin immediately.
 
  • #20
Israeli data boosts case for booster shots:
https://www.cnbc.com/2021/08/17/cov...w-israel-data-is-building-case-in-the-us.html

NIH director says new Israeli Covid data is building case for booster shots in the U.S.

  • Data from Israel on the effectiveness of Covid-19 vaccines over time is causing U.S. health leaders to rethink their position on vaccine booster shots in the U.S., NIH Director Dr. Francis Collins said Tuesday.
  • Israel released new data Monday showing a reduction in the effectiveness of Pfizer’s Covid vaccine against severe illness among people 65 and older who were fully vaccinated in January or February.
 
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  • #21
For those who get flu or other virus shots regularly, do you all get boosters for them too? Was hoping the COVID shots would last a "long time," but if they really are waning after just six months that's a bummer.

Would yet another booster be needed after the first booster too (or, we just don't know yet)?
 
  • #22
kyphysics said:
For those who get flu or other virus shots regularly, do you all get boosters for them too? Was hoping the COVID shots would last a "long time," but if they really are waning after just six months that's a bummer.

Would yet another booster be needed after the first booster too (or, we just don't know yet)?

A 3rd or 4th booster shot is not uncommon among many vaccines in use (e.g. see the CDC's recommended childhood vaccination schedules https://www.cdc.gov/vaccines/schedules/hcp/imz/child-adolescent.html). It is not known how long immunity would be expected to last after a 3rd booster because we don't have any long term data after a 3rd booster shot. The 3rd booster will be a single shot (no need to get another shot 3-4 weeks after the booster, though time may tell if a 4th booster would be needed later).

The annual flu vaccine is a single injection (if you aren't getting an annual flu vaccine, I would highly recommend that you do). Annual flu vaccines are not necessarily needed to act as booster shots; rather, they are necessary because the influenza virus changes year-to-year enough that a different vaccine formulation is needed each year. This could also be the case for COVID-19 if new variants continue to emerge (however, it seems like the booster will be the original vaccine, not a vaccine modified to match the spike protein of Delta or other new variants). Companies are working on developing combined flu/COVID-19 vaccinations, which could be helpful if yearly COVID-19 vaccinations become necessary.
 
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  • #23
Just had my 3rd Pfizer shot today. In Oregon you simply attest you need it, show them (local Walgreens drug store) your paper VAXX card and you get the shot in under 10 min.
A grim warning from Israel: Vaccination blunts, but does not defeat Delta
“Now is a critical time,” Israeli Minister of Health Nitzan Horowitz said as the 56-year-old got a COVID-19 booster shot on 13 August, the day his country became the first nation to offer a third dose of vaccine to people as young as age 50. “We’re in a race against the pandemic.”

His message was meant for his fellow Israelis, but it is a warning to the world. Israel has among the world’s highest levels of vaccination for COVID-19, with 78% of those 12 and older fully vaccinated, the vast majority with the Pfizer vaccine. Yet the country is now logging one of the world’s highest infection rates, with nearly 650 new cases daily per million people. More than half are in fully vaccinated people, underscoring the extraordinary transmissibility of the Delta variant and stoking concerns that the benefits of vaccination ebb over time.

The sheer number of vaccinated Israelis means some breakthrough infections were inevitable, and the unvaccinated are still far more likely to end up in the hospital or die. But Israel’s experience is forcing the booster issue onto the radar for other nations, suggesting as it does that even the best vaccinated countries will face a Delta surge.
To try to tame the surge, Israel has turned to booster shots, starting on 30 July with people 60 and older and, last Friday, expanding to people 50 and older. As of Monday, nearly 1 million Israelis had received a third dose, according to the Ministry of Health. Global health leaders including Tedros Adhanom Ghebreyesus, director-general of the World Health Organization, have pleaded with developed countries not to administer boosters given that most of the world’s population hasn’t received even a single dose. The wealthy nations pondering or already administering booster vaccines so far mostly reserve them for special populations such as the immune compromised and health care workers.
 
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  • #24
nsaspook said:
Just had my 3rd Pfizer shot today. In Oregon you simply attest you need it, show them (local Walgreens drug store) your paper VAXX card and you get the shot in under 10 min.
Interesting. Did they say the dosage was similar to shot #1 or # 2? I know second shots are supposed to be stronger. Or, ..possibly different (e.g., having a strength in between 1 and 2...stronger than 2, etc.)?

Very surprised they let you do it so quickly. Albeit, I've seen articles that U.S. is prepping to let lots of people get their boosters soon anyways. Just didn't know you could do it that quickly!
 
  • #25
kyphysics said:
Interesting. Did they say the dosage was similar to shot #1 or # 2? I know second shots are supposed to be stronger. Or, ..possibly different (e.g., having a strength in between 1 and 2...stronger than 2, etc.)?

You are incorrect. According to the paper describing the Pfizer phase 3 clinical trial, both the shots had the same amount of vaccine (30 µg). The Moderna vaccine also consists of two shots containing equal amount of vaccine.

According to the Pfizer press release on the booster shot, the thrid dose is also a 30 µg dose, the same amount administered in shots #1 and 2.
 
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  • #26
Ygggdrasil said:
You are incorrect. According to the paper describing the Pfizer phase 3 clinical trial, both the shots had the same amount of vaccine (30 µg). The Moderna vaccine also consists of two shots containing equal amount of vaccine.

According to the Pfizer press release on the booster shot, the thrid dose is also a 30 µg dose, the same amount administered in shots #1 and 2.
Thanks for the correction. A quick Google search indeed returned the same info.

I had mistaken the "stronger" reaction to Dose 2 with stronger content! Good to know. 👍
 
  • #27
kyphysics said:
Interesting. Did they say the dosage was similar to shot #1 or # 2? I know second shots are supposed to be stronger. Or, ..possibly different (e.g., having a strength in between 1 and 2...stronger than 2, etc.)?

Very surprised they let you do it so quickly. Albeit, I've seen articles that U.S. is prepping to let lots of people get their boosters soon anyways. Just didn't know you could do it that quickly!

They don't technically call this shot a "booster". A weakened immune system is the requirement for 3rd shot now. People with sickle cell disease and similar deficiencies have possible weakened immune systems so they currently qualify for it in the US.
 
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  • #28
nsaspook said:
They don't technically call this shot a "booster". A weakened immune system is the requirement for 3rd shot now. People with sickle cell disease and similar deficiencies have possible weakened immune systems so they currently qualify for it in the US.

Pfizer refers to the shot as a "booster dose" in their press release: https://www.pfizer.com/news/press-r...ntech-announce-submission-initial-data-us-fda

While the CDC did previously recommend a 3rd shot for immunocompromised people, the US government announced plans today to make booster doses available to all adults in the US on Sep 20: https://www.hhs.gov/about/news/2021...d-medical-experts-covid-19-booster-shots.html
(the HHS press release also refers to them as "COVID-19 booster shots")
 
  • #29
Ygggdrasil said:
Pfizer refers to the shot as a "booster dose" in their press release: https://www.pfizer.com/news/press-r...ntech-announce-submission-initial-data-us-fda

While the CDC did previously recommend a 3rd shot for immunocompromised people, the US government announced plans today to make booster doses available to all adults in the US on Sep 20: https://www.hhs.gov/about/news/2021...d-medical-experts-covid-19-booster-shots.html
(the HHS press release also refers to them as "COVID-19 booster shots")
That is for the 'booster'.

My shot was this.
https://www.cdc.gov/coronavirus/2019-ncov/vaccines/recommendations/immuno.html
  • This additional dose intended to improve immunocompromised people’s response to their initial vaccine series is not the same as a booster dose, given to people when the immune response to a primary vaccine series is likely to have waned over time.
 
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  • #30
A friend of mine is immunocompromised, but there are considerations that these people need to take. I was talking to a good friend about the booster, and they responded

"Yep I saw that, I'll ask my specialist about it this week but I'm sure she'll think it's a good idea. The only thing is that anything that can elicit an immune response can make my flare even worse so we may want to be thoughtful about how we time it, especially if we're switching my medication."

So it's not like anyone that is immunocompromised should just go out and get the booster. PLEASE TALK TO YOUR DOCTOR IF YOU HAVE HEALTH ISSUES!
 
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  • #31
Evo said:
A friend of mine is immunocompromised, but there are considerations that these people need to take. I was talking to a good friend about the booster, and they responded

"Yep I saw that, I'll ask my specialist about it this week but I'm sure she'll think it's a good idea. The only thing is that anything that can elicit an immune response can make my flare even worse so we may want to be thoughtful about how we time it, especially if we're switching my medication."

So it's not like anyone that is immunocompromised should just go out and get the booster. PLEASE TALK TO YOUR DOCTOR IF YOU HAVE HEALTH ISSUES!
Sure, keep them in the loop but it is a patient-instigated process without a lot of hoops to get a third dose for those that qualify. A lot of us had this discussion about a possible 'booster' with a medical professional when we received our first shots and have been waiting (some have gamed the system on their own for a 3rd) for that extra shot during this Delta wave of infection.

IMO If you're immunocompromised, start the process now before the September booster rush clogs the system.

https://www.kptv.com/news/area-pharmacies-prepare-for-third-covid-19-vaccine-dose/article_1594948c-0083-11ec-bdde-a32f44164a4c.html
"We're anticipating it to be a very busy season for us,” Daniel Lee, pharmacy manager at Fairley's Pharmacy in Northeast Portland, said. “Of course, that's during a flu season as well, so we do tons of flu vaccinations."

Lee said people are still trickling in for their second doses, but requests for first doses of vaccine have pretty much dried up. Lee does expect a rush once vaccine boosters become available.

"We're going to set up an online portal where people can sign up for appointments,” Lee said. “It's going to be 15-minute slots so we can streamline for people to get vaccines."
 
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  • #32
Ygggdrasil said:
While the CDC did previously recommend a 3rd shot for immunocompromised people, the US government announced plans today to make booster doses available to all adults in the US on Sep 20: https://www.hhs.gov/about/news/2021...d-medical-experts-covid-19-booster-shots.html
It looks like a booster is in the cards.

That same article states:
We are prepared to offer booster shots for all Americans beginning the week of September 20 and starting 8 months after an individual’s second dose.

Cheers,
Tom
 
  • #33
re: 8 months

Some of the data seem to suggest waning vaccine efficacy 4-6 months after Dose #2 (a Pfizer study showed a drop down to ~84%, per my original post/article). Any idea if people can get a booster before 8 months (heck, even as early as 4 months)?
 
  • #34
As most people probably know, a Pfizer booster shot has already been authorized (late-September 2021) for "select population groups": https://www.fda.gov/news-events/pre...biontech-covid-19-vaccine-certain-populations

Some important upcoming FDA meeting dates in October (2021) will involve boosters for Moderna and J&J, along with "mixing and matching vaccines:
The Food and Drug Administration’s independent vaccine advisory committee will hold three meetings in October to discuss Covid-19 booster shots, mix-and-match boosters and vaccines for children aged 5 to 11, the agency announced Friday.

The first two meetings, on Oct. 14 and 15, will cover booster doses of the Moderna vaccine and the Johnson & Johnson vaccine — both of which are authorized for use in adults. During the second meeting, the committee also will discuss data from the National Institutes of Health and the safety and efficacy of getting initial doses of one Covid vaccine and, later, a booster dose of another manufacturer's shot.
 
  • #35
Here's a question I have (not sure if it belongs more in the Biological/Medical section - either as a new thread or into existing one - or it's fine to ask it here...since I previously created this thread specifically on boosters, I figured I start with posting it here and allow for moderator or self-transport of it elsewhere if needed):

Is my understanding correct that boosters simply give our bodies "updated"/new active antibodies, which wane over several months? And, is it the case that the original full vaccine dosage(s) (i.e., pre-booster) already give us long-lasting (meaning years - not months) memory T and B cells, which help protect us still/continually?

Not sure if my conception/understanding of things is correct or not, but this is what I gather from readings over the past year or so. So, is it basically that the vaccines offer good long-term protection for everyone, but just that people getting boosters get a little "extra" protection (that will fade shortly still...which, if true, begs the question for me of whether constant boosters would be needed/recommended every few months for that extra protection of certain populations)?
 
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