We have to go by what we know now about the Covid vaccines, not by assuming that Covid vaccines will work exactly the same as other vaccines. Right know what the scientists say they know (by their definition of know which is we can prove so far about the Covid vaccines is that two shots (for the two used in the US) are needed for durable protection.
It does no good after a month? Where’s the evidence that supports this claim? IIUC, it’s accurate that we don’t know if one shot provides more than a few months of protection – that’s true as far as I know.
But that’s not the same as knowing that it provides no protection after a month.
There’s really no need to be condescending – I understand how the immune system works, thanks.
That is an assumption – we don’t know exactly how durable the antibodies are. Moreover, immunity varies considerably from one person to the next; we’re talking about averages. We’re also talking about knows, known unknowns, and unknown unknowns.
The most accurate way to describe the current investigation into immunity, durability of the vaccine, and herd immunity (if there is such a thing in this case) is that we’re still learning a lot as we go along.
To be absolutely clear: I am not proposing that we abandon plans for a second dose; I’m saying get more people vaccinated with the first dose now, which doesn’t mean every single person who wants a vaccine has to be accounted for before the second dose is administered. But we can probably delay the second dose in order to make sure that more people who need the first dose can get it and avoid the bottle neck that’s being caused right now in a pursuit of perfection – in a pursuit where we really don’t know what “perfect” looks like and where it’s very unlikely anyway.
Here’s another article, which basically suggests that the 2nd dose can probably be delayed. Not because they want more people to have the first dose, but because waiting might actually make the vaccine package as a whole more effective – as I’m saying, we’re learning a lot as we go.
Not going to play word games. It isnt known that sufficient protection lasts longer than weeks. To assume it does and act according good would be a poor bet to make with people’s health and lives. You certainly can make that choice to yourself, please don’t make it for me nor agitate for that choice to be made for me.
… said that while early results from Israel’s vaccine program are positive, there are still too many unknowns about a single dose’s efficacy beyond three to six weeks.”
“Until such time that there are good clinical trials that show that a single dose provides an equivalent level of protection, I don’t know that we should abandon our approach or create new policies,” he said.
It’s also not clear how one dose will perform against different coronavirus strains that are becoming more widespread, including separate strains that were first reported in the U.K., South Africa and Brazil.
“We’re running into uncharted territory,” said Deepta Bhattacharya, an associate professor of immunobiology at the University of Arizona, who was not involved with the study. “The uncertain issue is how long that protection is going to last against the current variants, as well as some of the ones that might get selected for if you wait too long.”
Bhattacharya said delaying the second dose up to six weeks, in line with the CDC’s guidance, seems reasonable. But beyond that, it may be too soon to tell, which means health officials may be faced with tricky decisions. Temte said that while early results from Israel’s vaccine program are positive, there are still too many unknowns about a single dose’s efficacy beyond three to six weeks.
“Until such time that there are good clinical trials that show that a single dose provides an equivalent level of protection, I don’t know that we should abandon our approach or create new policies,” he said.
It’s also not clear how one dose will perform against different coronavirus strains that are becoming more widespread, including separate strains that were first reported in the U.K., South Africa and Brazil.
“We’re running into uncharted territory,” said Deepta Bhattacharya, an associate professor of immunobiology at the University of Arizona, who was not involved with the study. “The uncertain issue is how long that protection is going to last against the current variants, as well as some of the ones that might get selected for if you wait too long.”
Bhattacharya said delaying the second dose up to six weeks, in line with the CDC’s guidance, seems reasonable. But beyond that, it may be too soon to tell, which means health officials may be faced with tricky decisions. Temte said that while early results from Israel’s vaccine program are positive, there are still too many unknowns about a single dose’s efficacy beyond three to six weeks.
“Until such time that there are good clinical trials that show that a single dose provides an equivalent level of protection, I don’t know that we should abandon our approach or create new policies,” he said.
It’s also not clear how one dose will perform against different coronavirus strains that are becoming more widespread, including separate strains that were first reported in the U.K., South Africa and Brazil.
“We’re running into uncharted territory,” said Deepta Bhattacharya, an associate professor of immunobiology at the University of Arizona, who was not involved with the study. “The uncertain issue is how long that protection is going to last against the current variants, as well as some of the ones that might get selected for if you wait too long.”
Bhattacharya said delaying the second dose up to six weeks, in line with the CDC’s guidance, seems reasonable. But beyond that, it may be too soon to tell, which means health officials may be faced with tricky decisions.
In some more time we may know enough to delay round two more than the 6 weeks allowed and I hope you end up being right on that, but we are not there yet.
From a NBC News site. I have read multiple stronger citations of the case but not going spend more time proving it to other’s satisfaction.
But of course. 
It was in the second link I provided in post #645. Here it is again. If you’d prefer not to read the article, here’s the relevant bit:
When the immune system first encounters a vaccine, it activates two important types of white blood cell. First up are the plasma B cells, which primarily focus on making antibodies. Unfortunately, this cell type is short-lived, so although your body might be swimming in antibodies within just a few weeks, without the second shot this is often followed by a rapid decline.
Then there are the T cells, each of which is specifically tailored to identify a particular pathogen and kill it. Some of these, memory T cells, are able to linger in the body for decades until they stumble upon their target – meaning immunity from vaccines or infections can sometimes last a lifetime. But crucially, you usually won’t have many of this cell type until the second meeting.
There’s more to it, but you’d need to read the (clear, interesting) article for that.
Whilst I’m very definitely on your side, this is somewhat over-egging it, at least so far as the Astrazeneca vaccine goes. Quoting from the product information approved by the EMA:
Evidence shows protection starts from approximately 3 weeks after first dose of vaccine and persists up to 12 weeks. A second dose should be given at a 4 to 12 week interval after the first dose
(Top of page 8)
And for the record the EMA assessment report does not go easy on the AZ application.
Regarding Pfizer and Moderna, so far as I know the case is that there is no evidence of continued efficacy beyond three or four weeks after a single shot. And we do not licence medicines on the basis of no evidence.
j
j, I think we are saying the same thing, just from different directions, so thank you for humoring me. I may have ‘over-egged’ that ‘one month’, but I did qualify it as “meaningful protection”.
I was not being condescending. I tried to be concise and to keep it simple, as your response gave no indication you’d read the linked articles or understood the mechanics of how the immune system worked. I thought if you had, it would be clear to you why delaying the second dose for the as long as it would take to get the first dose to everyone isn’t a good idea.
Since you’ve decided to interpret my attempts to sympathize and to explain the science as condescension, I’ve decided it’s best not to engage with you further.
I have made the same decision.
We are, but (a) I did medicines licensing for decades, so I’m a pedant on this; and (b) this thread is moving so fast I’m still 6 or 8 (long) posts off the pace!
j
It is! And I am tech-daft, so I’m very slow at finding cites, so I’m bowing out at proving to skeptics &/or denier’s satisfaction. ETA: “when will I ever learn?”
As long as we’re still friends, I’m good. I’m a wizen, grizzled old nurse, BTW, trained at Mass General.
I certainly appreciate the posts of the people here – @Treppenwitz, @BippityBoppityBoo, among others – who are speaking from their areas of training and expertise.
I know I can sometimes be prone to learning enough about something to be dangerous, and then speaking about it with (pretended) authority. I see that a lot in these threads, where someone is criticizing experts’ conclusions or cautions on the basis of their own, “well, I’ve read a lot about it, and I’m applying logic” sort of basis, without even having the data, let alone expertise of the experts. I know it is maddening to me when people do this in my own field of training and expertise.
So, thanks to those of you who are providing links to experts’ analysis and to news, and to those who are using your experience and expertise to help explain those to the lay people here, like me.
And you should read post 559 that shows one shot of the Astrazeneca vaccine has been shown to be effective at least 12 weeks out. There is no general principle of “vaccines are all ineffective after a month”.
I agree. I really don’t know much about medical stuff and the well explained posts and links are helping my understanding a lot.
Interesting indeed.
On the other hand, given the total lack of trial evidence, and weak association evidence, assuming that sufficient protection suddenly stops after a couple of weeks is a poor bet to make with people’s health and lives. 
And that bet is being made, by denying ‘first dose’ to the wider population.
That’s the nature of medical decision making: how people feel about the outcomes depends on how the proposition is stated, but decisions still have to be made.
The vaccine trials were not designed to show an optimum dosing regime and distribution regime. They were designed to exclude, with certainty, the possibility that the vaccine was worthless or dangerous, because those were the important facts that needed to be established. Anything after that is a bonus.
But there’s a way that’s known to work, and work very well. And then there’s a way that is not known to work. If that way works well, it could provide a bigger benefit. But, if it doesn’t work as well as hoped, it could cause further problems and wasted resources.
In medicine, the practice is generally to go with the known good way, and not just make up a new way and hope for the best.
I’ve been happy to see a change toward listening to experts, and following medical advice. Certainly it makes sense to schedule 2nd shots at the outer limits of the study timing, to get as many first shots in as possible, but I would prefer following evidence-based practices, even if I have to wait slightly longer for a shot. I’m not going anywhere anyway.
I don’t disagree with the thrust of what you’ve posted. The point in question wasn’t whether to skip a booster; it was whether to delay the booster so that more of the initial dose could be spread around, knowing that production is increasing every day. I agree that we shouldn’t abandon all of what we know about vaccine science and procedure, but I wasn’t arguing that we should. I think we should make some reasonable, logical adaptations based on circumstances and need.
There is some evidence that memory B cells can survive for a long time. Certainly plasma cells (differentiated B cells that pump out antibodies) can hang out in the lymphatic system for years, sometimes decades.
T cells do it differently, as I recall. The initial memory cells don’t live as long, but they transmit that memory to new T cells. My memory cells aren’t working this morning so I have to look up how they do this. 
Nope. You’ve got me beat by a country mile. Keep on keeping on. I’ll chime in once in a while.