Covid shot?

A pilot buddy who is also a dermatologist recently got shot #2 and is choosing to self ground for 7 days. He is a very conservative airman and wants to be ultra sure the inoculation isn’t causing any flight issues
 
Took me three days to recover from the side effects of the second shot.
 
I’m behind the info curve....
  1. why 2 shots?
  2. Is #2 the same formulation and dose as #1?
  3. Why would #2 take you off your game more than #1?
 
Off topic, but a lot of people complain their son's are unable to walk for a year after their circumcision procedures:eek::confused::rolleyes:
 
I’m behind the info curve....
  1. why 2 shots?
  2. Is #2 the same formulation and dose as #1?
  3. Why would #2 take you off your game more than #1?

1. As is the case for vaccines for several other illnesses, apparently the manufacturer’s data showed they needed a second shot to get to the level of protection they wanted in the long run. A first shot may have given good protection for the first few weeks but then the body’s immune system wound back down and didn’t apparently establish a good enough “memory” for that invader to be as effective the second time, so by providing a booster you’re reminding your immune system that this is a bad guy who must be gotten rid of.

2. Identical. I’m helping our local Public Health agency give them and there is no difference. That said, the PREFERRED route is to do just that: if the first was Moderna, the second should be. There’s some new guidance, I believe, that one CAN receive a different second shot (Pfizer if you got Moderna and vice versa) but that’s not preferred.

3. Because your immune system is recalling what it learned with the first one. Remember, our immune systems didn’t evolve with vaccines - they evolved with real infections, so it responds more quickly the later times because it’s already made antibodies in the past AND it wants to get ahead of the infection. And unlike getting exposed to the infection a second time, where the number of virus cells that gets in is likely pretty low at the start, the vaccine is dumping a bunch of the antigen in pretty quickly, so the body responds more aggressively than if you were exposed a second time to the virus. But, actually, getting the reaction after the second dose is being seen as an indication your body built good immunity, so that’s a good thing.

This is all VERY simplified but should be pretty accurate.
 
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1. As is the case for vaccines for several other illnesses, apparently the manufacturer’s data showed they needed a second shot to get to the level of protection they wanted in the long run. A first shot may have given good protection for the first few weeks but then the body’s immune system wound back down and didn’t apparently establish a good enough “memory” for that invader to be as effective the second time, so by providing a booster you’re reminding your immune system that this is a bad guy who must be gotten rid of.

2. Identical. I’m helping our local Public Health agency give them and there is no difference. That said, the PREFERRED route is to do just that: if the first was Moderna, the second should be. There’s some new guidance, I believe, that one CAN receive a different second shot (Pfizer if you got Moderna and vice versa) but that’s not preferred.

3. Because your immune system is recalling what it learned with the first one. Remember, our immune systems didn’t evolve with vaccines - they evolved with real infections, so it responds more quickly the later times because it’s already made antibodies in the past AND it wants to get ahead of the infection. And unlike getting exposed to the infection a second time, where the number of virus cells that gets in is likely pretty low at the start, the vaccine is dumping a bunch of the antigen in pretty quickly, so the body responds more aggressively than if you were exposed after vaccination. But, actually, getting the reaction after the second dose is being seen as an indication your body built good immunity, so that’s a good thing.

This is all VERY simplified but should be pretty accurate.

The above answer to #2 is accurate for the vaccines we now have in the US. In some of the AstraZeneca trials, they used a half-dose for the first shot, and a full dose for the second. That was done accidentally at some trial sites, but the results looked pretty good. I'm actually not sure which protocol they used to get approval in the UK, but in any event, they haven't submitted for approval or for an Emergency Use Authorization in the US. They're testing a single dose protocol now, so it's not impossible that it will be the one that gets approved in the future.

J&J will be filing an EUA for their single-dose shot in the very near future, but they are testing a two-dose protocol, so it's possible that we'll see that one down the road.

Finally, the Gamaleya Institute's Sputnik V vaccine actually uses two different shots in their two dose protocol. The shots use completely different adenovirus vectors, to try and avoid an immune response to the vectors themselves.
 
So my schoolhouse got our 2nd shots this week.

One interesting observation is that the reaction to shot 2 is very similar to responses to the actual virus in that no two people had the exact same side effects.

Some were laid up for 24 hours with fever, chills and every side effect on the info card and others felt absolutely nothing. Age did not seem to matter. Everyone (even worst cases) felt normal by the end of day 2.

I was middle of the road. Woke up in the middle of the night feeling restless and felt flu like aches in the morning, but no fever. Took two Tylenol and felt fine. Still achy that night, but normal on day 2.
 
The above answer to #2 is accurate for the vaccines we now have in the US. In some of the AstraZeneca trials, they used a half-dose for the first shot, and a full dose for the second. That was done accidentally at some trial sites, but the results looked pretty good. I'm actually not sure which protocol they used to get approval in the UK, but in any event, they haven't submitted for approval or for an Emergency Use Authorization in the US. They're testing a single dose protocol now, so it's not impossible that it will be the one that gets approved in the future.

J&J will be filing an EUA for their single-dose shot in the very near future, but they are testing a two-dose protocol, so it's possible that we'll see that one down the road.

Finally, the Gamaleya Institute's Sputnik V vaccine actually uses two different shots in their two dose protocol. The shots use completely different adenovirus vectors, to try and avoid an immune response to the vectors themselves.

Of note, talking to some healthcare professionals who’ve had COVID and then got the vaccine, it was shot 1 that had the most side effects for them.
 
Just got my second yesterday at noon. Let's just say I was a bit premature in saying, "this is nothing."
How much of ATC has been vaccinated so far? Does this mean no more center controllers working a 750nm radius and the end of ATITAPA calls at class B airports?
 
Of note, talking to some healthcare professionals who’ve had COVID and then got the vaccine, it was shot 1 that had the most side effects for them.
I wouldn’t be surprised if those people had actually already been infected, possibly asymptotically, and the shot was their “second dose”.
 
I wouldn’t be surprised if those people had actually already been infected, possibly asymptotically, and the shot was their “second dose”.

That’s exactly it. The ones I talked to had been symptomatic so their bodies were already aware when shot 1 entered the body
 
I got my first dose recently. Other than arm soreness (which was about the same as the flu shot this year) I only experienced a little bit of tiredness. We did have one of our pilots get quite ill with the second dose, so i am not looking forward to that one:
 
I’m behind the info curve....
  1. why 2 shots?
  2. Is #2 the same formulation and dose as #1?
  3. Why would #2 take you off your game more than #1?
Two shots generate twice as much profit as one. So much so, that the first manufacturers out of the gate didn't even bother to study or seek approval for single doses. But there's evidence of very good immunity after the first shot, and once the one-shot vaccines become popular, you'll see the two-shot regimens reduced based on "new" data. Maybe with a booster at some later date. I'd bet my shorts on it.
 
I’m behind the info curve....
  1. why 2 shots?
  2. Is #2 the same formulation and dose as #1?
  3. Why would #2 take you off your game more than #1?
Two shots generate twice as much profit as one. So much so, that the first manufacturers out of the gate didn't even bother to study or seek approval for single doses. But there's evidence of very good immunity after the first shot, and once the one-shot vaccines become popular, you'll see the two-shot regimens reduced based on "new" data. Maybe with a booster at some later date. I'd bet my shorts on it.
The article linked in post#16 explains all 3 questions.
 
I’m behind the info curve....
  1. why 2 shots?

Because the phase I/II trials for both BioNTech/Pfizer and Modernas product showed that this produces the maximal immunologic reaction at acceptable side effects. Pfizer tested 10/30/100mcg of mRNA in their product, Moderna tested 25/100/250mcg. Both arrived at the middle dose as the one that works best.

  1. Is #2 the same formulation and dose as #1?
Currently yes. That may change and it may be different for boosters that we may or may not need in the future.

  1. Why would #2 take you off your game more than #1?

Because your immune system does about 10x the work the second time around.

Below are the levels of antibodies measured at different points during the Pfizer phase I/II trial:

RBD binding IgG

1st dose 30mcg @ 3wk: 1536IU
2nd dose 30mcg @ 1wk: 27,872IU
2nd dose 30mcg @ 2wk: 16,166IU

So 2 weeks after the second 30mcg dose, you have 10x the antibodies that you had 3 weeks after the initial dose. Your immune system reacting is what releases the substances that give you the muscle aches and chills.
 
I got my second dose last Thursday morning. Worked all day scooping grain and driving trucks, felt a bit off by 5pm. By 8pm had the worst headache of my life and a fever. Fever broke around 4am, and I finally got a couple hours sleep. Was fatigued all day, but able to function. By Saturday am was feeling fine and even worked out.

My dad (75) felt no effects from either dose. My guess is that my immune system is more active.

He had the Pfizer shot while mine was Moderna. Anecdotally, friends from the fire service generally had a much more adverse reaction to the Moderna vaccine than the Pfizer. Can't quite figure that one out.
 
He had the Pfizer shot while mine was Moderna. Anecdotally, friends from the fire service generally had a much more adverse reaction to the Moderna vaccine than the Pfizer. Can't quite figure that one out.
From the article linked in post#16:
"The provocative nature of mRNA might help explain why Moderna’s shot, which contains three times as much of the genetic material as Pfizer’s, was linked to more side effects in clinical trials."
 
He had the Pfizer shot while mine was Moderna. Anecdotally, friends from the fire service generally had a much more adverse reaction to the Moderna vaccine than the Pfizer. Can't quite figure that one out.

While the products are formulated differently, every dose of moderna contains 3x the amount of mRNA than the Pfizer product. There may be a bit of a dose effect. I would have to pull up their phase III data to see whether participants in Pfizer's vs Modernas trials reported different levels of those expected symptoms.
 
We're 80 and 82. Both of us had sore arms, were restless and had trouble staying asleep the first day.
Sore arm the second day and that was all.
We got the Moderna.
Our worst side effect was the long long line they expected us old farts to stand in. :eek:
 
We're 80 and 82. Both of us had sore arms, were restless and had trouble staying asleep the first day.
Sore arm the second day and that was all.
We got the Moderna.
Our worst side effect was the long long line they expected us old farts to stand in. :eek:
Got my first shot Wednesday. I expected long delays. Nope - I was their first patient of the day, and they were waiting for me. The only delay worth mentioning was the 15-minute observation period
afterwards (to guard against adverse reactions. So I was astonished - this happened after making the appointment only the day before. Previously I had registered with another provider - and got an
appointment date of May 21!.

Dave
 
The article linked in post#16 explains all 3 questions.
It actually doesn't answer the first question. Here's an article specifically discussing why two shots might be better than one in theory, but you'll note that for Pfizer and Moderna, the bottom line is that both grant significant immunity after one shot, and we really don't know how effective one dose would be longer term because they didn't bother to test that.

Moderna

According to a document the company submitted to the FDA, the Moderna vaccine can provide 80.2% protection after one dose, compared to 95.6% after the second (in people aged 18 to 65 – it's 86.4% in those over 65). As with the Pfizer vaccine, all participants in the phase three trial received two doses of the vaccine or a placebo within a single set time period – in this case, 28 days – so it's not yet known whether the immunity from a single vaccine would continue, or drop off after this stage.

https://www.bbc.com/future/article/20210114-covid-19-how-effective-is-a-single-vaccine-dose
 
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Look on the bright side: that means it's working, right? :)

Yeah, that’s what I read but man, I could barely get out of bed today. I took an extra day off work beyond the 48 hrs because I’m hearing it lasts for 3 days.
 
Moderna booster.
1st vaccine ~Jan 12th.
Was told to expect a booster on Feb 10th.
Many showed up only to be sent away; "we did not receive the vaccine from the supplier and have not been told when to expect it." So no booster.
This week was a weather/utilities outage; So no booster.
What do the experts say about getting the 2nd dose at 6, 8, 10 weeks instead of 4?
Start over? Get a third one at 4 weeks from the 2nd dose?
 
Had my 2nd Moderna Monday at 9:30 am. At 9:30 pm bad chills and a slight fever hit me. Didn’t sleep very well. But by later in the day Tuesday I was feeling not too bad. Actually I donated blood late that afternoon. Today I feel fine.
 
What do the experts say about getting the 2nd dose at 6, 8, 10 weeks instead of 4?
Start over? Get a third one at 4 weeks from the 2nd dose?

The current guidance is to just take the second shot whenever you can get it, even if you are outside of the official 'window'. As currently having or not having the vaccine doesn't change what you can and cannot do, it really is of little consequence whether the two doses were given in the 'correct' spacing. That 3 or 4 week spacing is just what the respective manufacturers decided on for their phase I/II trial. With more time to spare, they may have done a couple of permutations of 4, 6, 12 week differences and using variable doses. But they didn't have that time, so they came up with a plan, tested whether it works when it looked like it did, that's what they based the next steps on.
 
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Got the first shot (Moderna) 3 hours ago. So far, so good! Vaccinations have always been a non-event for me, including the dreaded 2nd shingles shot last year, so we'll see if my luck holds and I avoid noticeable side effects with this one.
 
Two shots generate twice as much profit as one. So much so, that the first manufacturers out of the gate didn't even bother to study or seek approval for single doses. But there's evidence of very good immunity after the first shot, and once the one-shot vaccines become popular, you'll see the two-shot regimens reduced based on "new" data. Maybe with a booster at some later date. I'd bet my shorts on it.

It actually doesn't answer the first question. Here's an article specifically discussing why two shots might be better than one in theory, but you'll note that for Pfizer and Moderna, the bottom line is that both grant significant immunity after one shot, and we really don't know how effective one dose would be longer term because they didn't bother to test that.



https://www.bbc.com/future/article/20210114-covid-19-how-effective-is-a-single-vaccine-dose

Then there's this....
https://www.nejm.org/doi/full/10.1056/NEJMc2036242?query=NC
 
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