It does make me more resolute in my plan to continue hiding out in my apartment until 2 weeks past the 2nd dose, for sure. A lot of people think I’m insane for doing this.
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A very necessary surgery for a loved one is cancelled again. Best case scenario is to keep taking opiates past the point of functioning including parenting or remembering a conversation
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The vaccines are not 100% effective, even after being fully immunized. I’ve read the rates for both Moderna and Pfizer have been adjusted downwards to 90%. I’m not sure exactly 90% of what. Does that mean in the trials, where half got the vaccine and half got a placebo, that 9 out of 10 people who subsequently got covid were unvaccinated? Or does it mean if 10 vaccinated people are exposed sufficiently to someone with covid, one of them will get sick?
The effectiveness is somewhat less before full vaccination. I’ve heard (here I think) that the vaccine is 80% effective two weeks after the first injection.
tldr; vaccines are not 100% effective; that’s why measures like masks and social distancing are still recommended.
ETA I hope you loved one makes a full recovery. I’m sorry they are ill.
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Well, shit. My younger kid’s school is shutting down for a week. They had 7 positive tests Friday/the weekend and half the in-person classrooms (including LB’s) were quarantined, so they are shutting down the whole place out of an excess of caution.
The teachers have long since had the chance to be vaccinated (and were permitted/encouraged to cancel their classes–both in-person and online teachers could have an “asynchronous day” where they post work but don’t do any live lessons) so this is presumably kids being exposed through, dare I guess, families who are too excited to get back together and not taking precautions?
In happier news, I’ve had my second shot Saturday! I was pretty sick yesterday morning but I took some Aleve and was better by the time it wore off.
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That’s not an excess of caution; it’s an outbreak. Sorry it’s at LBs school.
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Sorry, I meant something more like abundance of caution? Like there is no rule that calls for shutting down but it seems prudent, if I understand correctly. My impression is that all the kids are in separate classes… I thought an outbreak was if there is spread within a building. Anyway, it’s a lot and I’m sure it’s the right call.
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The percentage is compared to the control group. In the study, (for example) if the groups are the same size and have the exact same exposure conditions, if 100 people in the control group get covid and 5 people in the vaccine group get covid, theoretically a 95% effective vaccine prevented 95 infections out of 100 exposures that would have caused an infection.
The percentage is the reduction in risk of getting the disease.
A vaccinated person is 95% (or 90%, apparently) less likely to get the disease than an unvaccinated person.
So the number of people who are infected when vaccinated depends on the rate of spread of the disease itself. (At 95%- if 10% of the placebo group got covid, you’d expect that 0.5% of the vaccinated group to get it; if 2% of the placebo group got covid, you’d expect .1% of the vaccinated group to get it- if I did my math right.)
It’s a lot, and yeah, I don’t know official definitions of outbreak in this context - if it means they all catch it from each other, I don’t know how we’d ever know in our situation with basically no contact tracing (I assume it’s like that where you are; it is here).
Anyway, sorry you have to deal with it.
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I’d like to hear the result! Going to ask my eye specialist about it. I’m seeing her a week after my second dose!
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What I’m trying to understand from the percentages - once I’m vaccinated, does my risk go up with the number of encounters?
For example, let’s say we have 90% effectiveness and a group of 100 vaccinated people. Does this mean that 10 of those people are more susceptible? i.e. 90 of those people are effectively prevented against disease no matter how many infected people they come in contact with? I’m assuming typical interactions like you would have with people at a grocery store or gym.
Or, does it mean that I’m protected in 9 of 10 encounters with an infected person, but if I have enough encounters, it’s likely I will get it?
Does it make sense what I’m asking?
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I’m not up on my stats any more, but it works something like: each time you encounter a person, you are rolling the dice. No encounter == not rolling the dice == no chance of infection. So short answer, yes, risk increases with number of encounters.
The more times you roll the dice, the more opportunities you have to get the winning (or in this case, losing) number. But I don’t think we have a good way to estimate how many sides that die has, to beat the analogy into the ground. Currently we can only say that of two groups who played the same type of game, the vaccinated group got the losing number 90% less than the unvaccinated group. Hopefully those groups were rolling the dice approximately the same number of times, etc but controlling down to that level isn’t possible/ethical in broad human trials.
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I think I get what you’re asking? And I think the answer is both, and neither. Lol. Basically, the efficacy numbers just reflect what did happen in trials. And from that we extrapolate what will happen, but the numbers themselves don’t tell us the “why” behind everything. But we do know some people are more susceptible, they have an incomplete immune response to the vaccine for example. We also know that the higher the viral load the more likely you are to still get sick, which happens with more and longer exposures generally. So i think it’s both. If that makes sense.
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That’s why really big trials, and random and blind group assignment are so important. We just have to hope (and it pencils out well, generally) that those steps are enough to control for everything.
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This is also a relevant time to bring up what the trials did and didn’t look at. The efficacy numbers I believe refer to documented cases at all. But we also saw a major difference in severity of cases between the two groups. So getting Covid unvaccinated is going to be a different roll of the odds dice than getting Covid while vaccinated. If I remember correctly, there were no or basically no hospitalizations at all among the vaccinated group even in those who did get positive Covid tests?
Hoping someone who has dug in more deeply can weigh in.
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Yes, exactly!!
I might still be traumatized by an unbalanced experimental design that I inherited in grad school, and that was just soil ecology!! Not even close to human or even animal work! And of course because it was ecology there was no money to fix anything or get extra samples…
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It isn’t 9 out of 10 encounters, or 10 people in a group of 100.
It’s compared to your chance of getting it when not vaccinated.
I think it’s super hard to quantify what the chance of getting covid is for a non-vaccinated person, but the vaccine trials show it is 90-95% less likely for a vaccinated person to get it.
So, an unvaccinated person isn’t 100% likely to get covid if they go the grocery store, maybe they have a 20% chance (number off the top of my head). So a vaccinated person going to the same store, would have say a 2% chance, at 90% efficacy.
Really the only way you can quantify the statistic though is like “an unvaccinated person french kissing someone with an active covid infection has a 99% chance of getting covid” (again, making that up though). A vaccinated person has about a 10% chance, at 90% efficacy.
This is where herd immunity comes in. The more people vaccinated, the less active covid infections, which means the total risk of getting covid decreases, so the vaccinated risk is even lower.
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Right now, it looks like all the vaccines are claiming 100% efficacy against severe covid.
Also, an infection, in all the vaccines given in the US was defined in the trials as showing at least one symptom, plus a positive test. So they didn’t look at asymptomatic cases, which is one of many reasons why they don’t know if vaccination prevents spread.
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This is my understanding as well. It’s also important to take into account case rates in your community because that helps to drive the 20% example number mentioned above.
Emily Oster made a spreadsheet to calculate risk. I haven’t played with it too much but I think you can customize for local conditions.
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Noooo, Johnson & Johnson 
Six possible cases of blood clots in women aged 18-49 in the US, out of 6.8 million doses. Four cases in the EU. They’re pausing use to investigate.
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