Evaluating necessity of Covid-19 vaccination in previously infected individuals • Hacker News Board

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#191

Post by Izkata » Thu, Jun 10, 2021, 4:58 AM UTC

phkahler wrote: post #103

refurb wrote: post #100

Earlier quoted context omitted.

I don’t see it in the abstract, but what was the infection rate for the unvaccinated? That’s your comparison. They also mentioned 0 infections in fully vaccinated which is odd as other countries are seeing a number of infections in their vaccinated front line workers. https://twitter.com/sporeMOH/status/1402637555263098884?s=20

>> They also mentioned 0 infections in fully vaccinated which is odd as other countries are seeing a number of infections in their vaccinated front line workers. No, they had infections in the vaccinated. They had 0 infections in the previously infected, although another poster pointed out that the vaccinated (but never infected) group is much larger than the unvaccinated but previously exposed. Frankly since the vac…

Immunity from infection does more than the spike protein, so it ought to be more robust against variants, even if one does show up that changes the spike protein enough to escape vaccines.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#192

Post by rolph » Thu, Jun 10, 2021, 4:59 AM UTC

IgorPartola wrote: post #183

krrrh wrote: post #161

Earlier quoted context omitted.

We don’t know that there is no downside which is why these vaccines were approved via Emergency Use Authorization. At the very least I and several people I know were absolutely flattened by the vaccines for a day or two. One guy I know had very low blood sugar for weeks afterwards and needed medical intervention. The vaccines are important in establishing herd immunity, but I don’t understand the desire to jab people…

Feeling symptoms of COVID after receiving the vaccine is a normal and expected result that makes common sense: your immune system is doing its job. The only possible long term side effect here is partial or total immunity from COVID. On the other hand you don’t know the long term effects of COVID either, but I would bet dollars to donuts that they are worse than from the vaccine, based on what we know as of today.

one of the other long term effects of covid transmission, is the opportunities given for variation and selection according to viral efficiency, in effect each infection is a crap shoot toward generation of recombinants, or molecular variants

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#193

Post by reducesuffering » Thu, Jun 10, 2021, 5:05 AM UTC

adventured wrote: post #113

symlinkk wrote: post #39

Earlier quoted context omitted.

Because openly stating this obvious fact would get you downvoted on here a few months ago.

> Because openly stating this obvious fact would get you downvoted on here a few months ago. Attempting to discuss it here will still commonly get you downvoted. HN is not a particularly rational forum. People make the mistake of thinking it is because a lot of engineers hang out here. Engineers are not especially rational, that's a common myth derived from failing to understand the way people mentally compartmentali…

Ok, essentially you’re saying the real number of cases is higher than the official numbers reported, because the official numbers only report ones confirmed by tests, and there are many people who got Covid and were never tested.

I think most on HN would agree with your assessment that the real number of cases are somewhat higher than the official count, although I haven’t seen any evidence indicating exactly how much higher or lower. The Dakota states did seem to taper off cases immensely before the vaccines were distributed, indicating a possible early herd immunity.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#194

Post by manwe150 » Thu, Jun 10, 2021, 5:12 AM UTC

nradov wrote: post #187

amanaplanacanal wrote: post #176

Earlier quoted context omitted.

I’d love to see real numbers of how many people have been infected, but I have no idea how you would get them. Do you have any suggestions?

The most accurate approach would be to do repeated blood tests of a large nationwide study population looking at both antibodies and memory T cells. The CDC really should have been doing that nationwide for the past year.

The Red Cross Blood Donation centers perhaps come closest to doing this. From their emails, it sounded like they never saw widespread active antibodies (until a few months ago).

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#195

Post by mlyle » Thu, Jun 10, 2021, 5:13 AM UTC

BeefWellington wrote: post #184

mlyle wrote: post #160

Earlier quoted context omitted.

Canada/the UK have been doing that. Odds are it does make things more effective rather than less, based on our experience with other vaccines. But IMO it's not wise, because it wasn't studied. Still, 2 huge peaks separated by 3-4 weeks provokes really big immune responses.

> Odds are it does make things more effective rather than less, based on our experience with other vaccines. But IMO it's not wise, because it wasn't studied. It has since been studied[1] (preprint) and that was exactly what was found -- delaying the second dose provoked a stronger response, similar to many other vaccines. [1] https://www.birmingham.ac.uk/news/latest/2021/05/covid-pfize...

Sure, so far preliminary data looks OK. I still don't think it was a wonderful roll of the dice-- it didn't lower susceptibility so much in the short term (because a single dose's efficacy is limited, especially in the old) and it could have made things much worse.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#196

Post by arwhatever » Thu, Jun 10, 2021, 5:15 AM UTC

waterside81 wrote: post #70

stavros wrote: post #28

Earlier quoted context omitted.

That's encouraging! I got COVID a few months ago and got vaccinated recently, seems like I should be unstoppable now.

Hey I'm curious, if you don't mind sharing, how do you think you got it? Throughout this whole pandemic, I'm still kind of amazed how people are getting it

Avoided it all year while traveling the country by only going to outdoor activities, and also getting groceries while masked.

Got it at Christmas from a gathering with only 3 other family members.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#197

Post by jacobolus » Thu, Jun 10, 2021, 5:27 AM UTC

jdminhbg wrote: post #180

rectang wrote: post #107

Earlier quoted context omitted.

The unvaccinated are still vectors for the infection of those who cannot be vaccinated, such as the immunocompromised. I personally don't think in terms of "blanked demonizing" people, but neither am I going to blanket-absolve all the unvaccinated — especially willful anti-vaxxers. Regardless, this study is good news — because it means that every person who is infected and then recovers contributes towards herd immun…

> The unvaccinated are still vectors for the infection of those who cannot be vaccinated, such as the immunocompromised Is it actually the case that immunocompromised people cannot be vaccinated? The ones that I know have been; as far as I know, the mRNA vaccines by virtue of not being based on live virus are not dangerous to those with weakened immune systems.

Immunocompromised people can safely get the vaccine, but it might not work, leaving them still vulnerable to the virus.

In recent studies something like half of organ transplant recipients did not produce antibodies after being vaccinated, and there have been a few cases where a group of vaccinated transplant recipients caught Covid (e.g. from a vaccinated nurse who had an asymptomatic infection) and had severe symptoms including some deaths.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#198

Post by wuschel » Thu, Jun 10, 2021, 5:31 AM UTC

reducesuffering wrote: post #2

Punchline: “The cumulative incidence of SARS-CoV-2 infection remained almost zero among previously infected unvaccinated subjects, previously infected subjects who were vaccinated, and previously uninfected subjects who were vaccinated, compared with a steady increase in cumulative incidence among previously uninfected subjects who remained unvaccinated. Not one of the 1359 previously infected subjects who remained u…

Two comments:

(1) A friend of mine who works as a doctor in one of the vaccination centers in South Germany told me that re-infection rates with problematic outcome after full vaccinations are ~5%. This is what they tell their patients in the information talk before the shot. Note that my friend could not give me a higher resolution of the data (age, etc).

(2) I think I wrote that in one of my prior comments ~ 9 month or so ago - Another medical doctor aquaintance of mine that was working in the local health department Corona group told me that in the town of Tuttlingen (pop ~ 100K) there habe been 9 re-infections with the SARS-CoV2. At the time there were only 7 known cases in literature.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#199

Post by jacobolus » Thu, Jun 10, 2021, 5:38 AM UTC

briefcomment wrote: post #182

barbazoo wrote: post #178

Earlier quoted context omitted.

I can imagine it being downplayed out of fear that it could slow down the vaccination program by pushing people over the edge that were hesitant to get vaccinated and possibly questioning covid-19 in the first place.

It's fine if those previously infected don't get the vaccine. I don't see why information on how natural immunity is effective would make people who haven't gotten Covid even less likely to get the vaccine.

There are many people who are convinced their respiratory infection earlier in the pandemic was Covid despite never having been tested. While some of those may plausibly have been Covid, many were surely flu or some other disease.

It would be a shame if such people avoided the vaccine under a disinformation-driven impression that the vaccines are risky, and ended up catching/spreading Covid later on.

Re: Evaluating necessity of Covid-19 vaccination in previously infected individuals

#200

Post by cbsmith » Thu, Jun 10, 2021, 5:56 AM UTC

phkahler wrote: post #101

spion wrote: post #88

Earlier quoted context omitted.

I know that seems like a large number but in the vaccine arm there were 20x more subjects and only 15 cases. So with the 1359 previously infected subjects, assuming identical behavior to vaccinated subjects, we would expect around 0.9 cases if vaccines were approximately equal to infection. So this study doesn't have enough statistical power to say how vaccines compare to previous infection. Could be better, could be…

>> So this study doesn't have enough statistical power to say how vaccines compare to previous infection. Could be better, could be up to 3 times worse within a high confidence interval. Could be. But it would be great if they'd just say having had a confirmed case is equivalent to getting the vaccine because several studies have now shown that to be roughly the case. It's also conventional medical wisdom although it…

Unfortunately, we have reason to believe that over time, the immune defenses from COVID-19 infection seem to decline, particularly in older folks. It'd be great if we had some definitive data on secondary infection rates, but until a lot more people get infected, we just won't have it.