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Is one vaccine dose enough if you’ve had Covid? What the science says

nature.com

21–30 of 44 posts

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#21

The study used 26 participants? Did I read that right? What is the preferred sample size to back these sorts of claims?

Not sure why they'd focus on a study out this week, there have been several others, e.g. the first 5 references in this Letter published a month ago: https://www.thelancet.com/journals/ebiom/article/PIIS2352-39...

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#22

Earlier quoted context omitted.

Did you not get an antibody test at some point prior to the vaccine? That would have given you an answer with 99% certainty if you used a good one.

I think they are relatively expensive, ~$200. Probably worth it though. We would need some form of official recognition of antibody tests though. Pretty sure most places that require vaccination don't accept antibody test results.

I believe the Red Cross tests for the antibody when you give blood, as well.

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#23
post #5
post #2

I wish there was an easier way to figure out if you had COVID. As someone who's only got one dose so far, I would gladly skip the second one if I knew for certain I had COVID before, so someone else could get my second dose.

[never mind]

The US is in desperate need of people who are willing to take all the vaccines the government has purchased for us. What’s the shelf life on the mRNA products? Looks like Moderna’s lasts for six months in the freezer. Pfizer for 30 days on dry ice, another 30 days in a regular freezer?

Lots of doses are going to get tossed. Most the people who are going to get the shot have gotten it already.

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#24

seems like there's some consensus on two "exposures" worth of immunity being valuable. any data on second shots for folks who took the J&J?

The cynical part of me thinks that J&J is only 1 shot because your body develops strong immunity to it adenovirus-26 vector, so a 2nd shot would get immediately killed off before its spike protein payload could take any action. Until your immunity to it wanes anyway.

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#25

Why doesn't getting Covid and then allowing your body to produce your own immunity not protect you from getting it again? As I understand the variants are not like the flu or the cold (yet!)

iirc for some reason the amount of antibodies you have falls sharply after 1-3 months and you're vulnerable again. anecdotally, a friend of a friend (EMT) had covid like 4 times before vaccines were available.

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#26
post #25

Why doesn't getting Covid and then allowing your body to produce your own immunity not protect you from getting it again? As I understand the variants are not like the flu or the cold (yet!)

iirc for some reason the amount of antibodies you have falls sharply after 1-3 months and you're vulnerable again. anecdotally, a friend of a friend (EMT) had covid like 4 times before vaccines were available.

Can someone explain why this would not be the case for vaccines?

If antibodies fall off quickly from an actual infection, why would this not also happen for the antibodies produced because of taking the vaccine?

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#27
post #25

Why doesn't getting Covid and then allowing your body to produce your own immunity not protect you from getting it again? As I understand the variants are not like the flu or the cold (yet!)

iirc for some reason the amount of antibodies you have falls sharply after 1-3 months and you're vulnerable again. anecdotally, a friend of a friend (EMT) had covid like 4 times before vaccines were available.

Antibody count falls at first, but relevant antibody-producing cells were found[0] to remain in the bone marrow. I suppose it is not the only determining factor in susceptibility to symptomatic infection, though.

I’d be curious if currently available vaccines stimulate such preexisting antibody-producing bone marrow cells of past COVID patients (which sounds more optimal on the face of it), or they trigger yet another variety of antibodies to be produced in addition to the “native” one.

[0] https://www.nature.com/articles/d41586-021-01442-9#ref-CR1 “Had COVID? You’ll probably make antibodies for a lifetime”

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#28
post #25

Why doesn't getting Covid and then allowing your body to produce your own immunity not protect you from getting it again? As I understand the variants are not like the flu or the cold (yet!)

iirc for some reason the amount of antibodies you have falls sharply after 1-3 months and you're vulnerable again. anecdotally, a friend of a friend (EMT) had covid like 4 times before vaccines were available.

Bullshit. SARS 1 produces immunity against COVID and every other coronavirus has natural immunity. Your friend had some colds, the flu, maybe COVID once, and potentially false positive tests.

Antibodies do drop but they're not the only part of the immune system. T cells have memory and will remember the antigen

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#29

> Research shows that a previous coronavirus infection plus one dose of vaccine provides powerful protection — but concerns linger This is one thing that’s been incredibly frustrating throughout this whole pandemic. Studies and research will show B, with no sign of A, however inertia/politics/fear/ignorance will continue to push A to the point of harm. An example - a local store was insisting on wiping down the entir…

> a local store was insisting on wiping down the entire checkout conveyor with alcohol between every single customer until very recently, when we’ve know for a long time that you won’t get COVID from that.

As someone from a country where running orders are still to disinfect often-touched surfaces (switches, door handles, office desks, etc.) I was surprised by this.

I went to check what CDC from US recommends. It turns out it's pretty much the same:

> Clean high touch surfaces daily. This includes tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks.

(from https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-si...)

So maybe wiping down the belt between every customer is a bit excessive, but it seems my sources don't agree with the "you don't get COVID from that" part.

Re: Is one vaccine dose enough if you’ve had Covid? What the science says

#30

Earlier quoted context omitted.

Did you not get an antibody test at some point prior to the vaccine? That would have given you an answer with 99% certainty if you used a good one.

Antibody tests were only widely available in July-August, so people who got COVID in Feb or March often didn't have high enough antibody counts by that point to flag positive on the tests.

That's not true.

The half-life of antibody levels has been estimated at 73 days. The antibody tests are quite sensitive, time has not been enough of a factor yet to produce false negatives. In a year or two it might be.

The only time concern is that you need to wait 2-3 weeks until after you recover from COVID to ensure you test positive.

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