Study shows how Covid-19 immunity wanes over time | Hacker News Reader

Study shows how Covid-19 immunity wanes over time

directorsblog.nih.gov

29 pointsnihkolberg16 comments

Key paragraph below. My question is what the baseline infection rate is for unvaccinated people. If it's much higher than 3.3 per 1,000 then there's less of a case for getting a booster.

> Among individuals 60 years or older who were fully vaccinated last January, the number of confirmed breakthrough infections was 3.3 per 1,000 people during the three weeks of the study. Those who were vaccinated in February and March had lower infection rates of 2.2 per 1,000 and 1.7 per 1,000, respectively. The data revealed a similar pattern in those aged 40 to 59 and those aged 16 to 39.

Not surprising when all of the people around me who are vaccinated keep getting covid. My coworkers wife came down with appendicitis after getting the vaccine and her mom got covid after being vaccinated as well.. my boss's dad got covid after being vaccinated. I work in an office with 4 other people so it's not like there is a high chance of that happening, but it did.

Either the immunity wanes over time or people who are vaccinated are taking more risks or something

Worth remembering that applying anecdotal experience to an entire world population in terms of generating statistics is unlikely to be accurate, and very much at risk of confirmation bias.

Most vaccines are only 65% efficacious in preventing infection from Delta. So even amongst 100% double vaccinated crowds, 1 in 3 will contract covid if exposed.

The real difference is the reduction in serious complications and hospitalization and death. Going off stats from my state (NSW in Australia), 78% of people hospitalized were completely unvaccinated. 19% had one shot. 2% had both shots. Those numbers are really, really hard to argue against IMO.

edit: I should add, it's even worse when you consider that 80% of our state is 100% vaccinated, meaning that the 78% figure above is true despite being from a pool that makes up only 20% of our state's population.

I mean I'm not basing anything on personal anecdotes, I'm simply stating that my personal observation supports what a scientific study says. When there is evidence to back up an anecdote it ceases to be an anecdote.

And it's not like I'm making decisions based on my coworker's family members getting covid lol. This is a much more complex issue, and that really kind of reduces the entire thing to the point of absurdity.

> I'm simply stating that my personal observation supports what a scientific study says. When there is evidence to back up an anecdote it ceases to be an anecdote.

That's actually a really good example of confirmation bias :) it can be a real sneaky logical fallacy! In this case you have no controls in place to verify the what, why, or how of those people's infections, but because it matches what you think it should you've accepted it as further evidence that confirms the proposition of the study. Anecdotal evidence remains anecdotal whether or not it correlates with a position in either direction.

> it can be a real sneaky logical fallacy!

So is the argument from fallacy... If you want to argue against science then you should bring your own evidence because claiming that someone agreeing that their observations match 3rd party scientific observations is a fallacy is beyond silly.

Just a small correction. 1/3 of those who would have gotten covid when not vaccinated will get covid.

Based on this, it should be expected that the 2% figure you quoted would increase over time. I would say in Australia a lot of people are still in the "honeymoon phase" of immunity where it hasn't started to significantly wane amongst the population of the fully vaccinated.

Yes exactly right, which is what the Israeli data has indicated. It's not a huge decrease, but there's a definitive slow decrease in efficacy - worth noting it's nearly entirely against the Delta variant again though. So even though 2 shots will continue to keep you moderately safe, the argument is that there's no good reason to not get a booster (just like a flu shot every year).

edit: to quote specifics from the study

> Our findings are in line with findings from the randomized trial of the BNT162b2 vaccine, which showed a reduction in vaccine efficacy against symptomatic infection from 96% in the first 2 months after vaccination to 84% at 4 to 7 months after vaccination, when averaged over all age groups combined

In CS, part of being an expert is knowing what you don't know. Each incorrect prediction or contradiction decreases trust and legitimacy. I'm disappointed in our institutions for marketing the COVID shot as a one-time vaccine. What was the basis for thinking this wouldn't happen?

Did that really happen? The importance of getting a vaccine was stressed but very little was said about the endurance of that protection. Many vaccines require boosters. It is also important to acknowledge that the original COVID-19 was essentially defeated until the Delta variant came about. So instead of imagining that authorities said this would be a one time vaccine it might be more realistic to accept that authorities said no such thing, that variants are unpredictable, and that the endurance of any particular vaccine is difficult to determine, especially early on.

> Many vaccines require boosters.

There is no other vaccine routinely administered to large numbers of people that requires a booster every 6-12 months in the general population.

Of the vaccines that require ongoing boosters in the general population, Tdap is probably the most common, and the booster is every 10 years.

The "flu shot" is not an annual booster. It is a different reformulated vaccine every year that, in the case of the trivalent vaccines, targets the 3 strains of influenza that are predicted to be most prevalent in the coming flu season.

It's true that they pick different strains each year but we would still need annual flu shots if that wasn't the case because efficacy goes down by almost 10% each month: https://academic.oup.com/cid/article/73/4/726/6104243

No, you wouldn't. If influenza viruses didn't mutate the way they do, you'd inevitably get infected (whether vaccinated or not) and you would have natural immunity such that the benefit of getting vaccinated every year would be miniscule unless you were in a high-risk category. So in this scenario, an annual "flu shot" wouldn't be a thing for the general population.

That's true in the sense that if you don't want to prevent people from getting influenza you don't have to give them a vaccine.

Otherwise, even if natural immunity to influenza lasts for a lifetime, most people don't get influenza very often (however people often confuse colds and influenza and don't realize this), so merely having a large existing number of strains would make it incredibly difficult to get natural immunity to all of them even if it wasn't continuing to mutate.

If you don't want people to be able to get influenza 10 times in their lifetime you would still have to give flu shots, and since their effectiveness decreases rapidly you would have to do this every year.

And that's assuming that natural immunity really lasts longer than flu shots.

Anyway that whole point is somewhat irrelevant to your original point that I was responding to that no other vaccines require boosters but it is clear based on your response that you are essentially engaging in circular reasoning (you don't think that boosters are required because no other vaccines require boosters, therefore flu vaccines are not boosters, therefore no other vaccines require boosters).

It's kinda implied when you hear 'fully vaccinated people do not require a mask'. I think that it's a bit of a stretch to come to the conclusion that that implies the vaccine is a magic bullet, but I have been surprised IRL by people who really do think that and would expect to be completely immune after getting a few mRNA shots. I was not surprised by their annoyance at learning that wasn't the case.

I think you are coming from a place of having a bit more knowledge than the absolute minimum you'd pick up through osmosis by never doing any research or due diligence. I wouldn't be surprised to hear that awareness campaigns deliberately ignored facts that might make the vaccine sound less appealing. It's hard to make good decisions if you don't really have a full picture.

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