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Comment by officialjunk | Hacker News Reader

note there is not a claim this vaccine prevents infection, only lessens symptoms, meaning you are still contagious.

"We all expect an effective vaccine to prevent serious illness if infected. Three of the vaccine protocols—Moderna, Pfizer, and AstraZeneca—do not require that their vaccine prevent serious disease only that they prevent moderate symptoms which may be as mild as cough, or headache."

"Prevention of infection is not a criterion for success for any of these vaccines. In fact, their endpoints all require confirmed infections and all those they will include in the analysis for success, the only difference being the severity of symptoms between the vaccinated and unvaccinated."

https://www.forbes.com/sites/williamhaseltine/2020/09/23/cov...

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It is true that for these initial protocols, they are only testing becoming symptomatic versus prevention of transmission. That said, all the trials (at least in phase 1/2) are also looking at antibody levels[1][2], which would indicate less likelihood of transmission.

Remember, all these vaccines aren't yet applying for full approval, but an EUA (Emergency Use Authorization). I fully expect that the FDA would want to see data on transmission before full approval; but that is harder to acquire, so it makes sense they wouldn't wait for that specific data.

As someone in the AZD12222 (AstraZeneca/Oxford) trial, I can confirm that they are following all participants for a full 2 years. In this time (versus the ~3 months each Phase 3 trial has run for), there will be much more time to see if these vaccines prevent transmission, not just prevent symptoms.

With all that said, many thousands of live will be saved by getting these vaccines out now, even if they are only partially effective. After all, someone who can't get sick can return to a more normal life, since they won't have issues if they were to get SARS-COV-2 infection later on.

[1] https://biology.mit.edu/undergraduate/current-students/subje... [Lecture 10, with a NIH researcher who worked on the Moderna vaccine]

[2] https://www.thelancet.com/journals/lancet/article/PIIS0140-6... [Phase 2/3 study of AstraZeneca vaccine, figure shows neutralizing antibody levels]

That forbes article is quite weird. The trials have obviously been designed to find out if the vaccine helps prevent serious illness, as fast as possible. Questions like 'can vaccinated people still spread covid' are much harder to answer in a trial. Perhaps they'll look at that later.

Right, but are there any vaccines out there that protect against disease but don’t prevent transmission? I thought that’s what herd immunity was all about.

You're asking if there are vaccines that do not lead to sterilizing immunity? Yes.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7296151/

As per the article, the flu vaccine looked at didn’t provide sterilizing immunity, but did significantly lower viral titre in the lungs.

So I guess the question is - even if not sterilizing immunity, would these vaccines significantly reduce (but not eliminate) transmission?

With this being the case, how does it even make sense for companies like Ticketmaster and Quantas to announce that they'll require their customers to be vaccinated?

Yeah, 90-95% of your customers won't have symptoms if they get infected. But they'll still have the ability to pass on that infection to someone who wasn't vaccinated, or falls into the 5-10% of people who the vaccine isn't effective for.

Obviously the vaccines have benefits, especially for high risk populations. But I see very little benefit to these corporations requiring their customers to have it, since their customers can still be infected and spread the virus.

The issue here is that there's just not data on how contagious the small percentage of vaccinated people who contract COVID may be. Realistically, all the indications we have so far are that there is some correlation between how much you experience symptoms and how likely you are to infect others. It appears that people who never get symptoms (true asymptomatic carriers) are fairly rare and also really not very likely to infect others. Most of the asymptomatic "super-spreaders" which have been reported were actually pre-symptomatic. It's theoretically possible that people who are vaccinated and become infected (which looks like only a fairly small percentage) will still be able to spread the virus, but in all likelihood that ability will be greatly diminished.

For certain meanings of making sense, it's perfectly sufficient if either a number of airline managers or a number of airline customers simply don't understand that possible limitation of a vaccine's effect. And both are very likely. And it can make sense even beyond that, because a vaccine that doesn't completely rule out infectivity can still be reasonably expected to weaken and/or shorten infectivity.

Companies want customers, as a business decision is makes sense to require vaccinations because if they check that means governments will let them open. Ticketmaster wants to get whatever the big name acts are on stage with a full house. If they check vaccination status they can sell out a large auditoriums in February to nurses and a few lucky others. If they wait until governments allow large venues to open up they might be waiting until next fall. That is a large amount of money they are leaving on the table. Likewise, Quantas flys international to places that lockdown as eliminated covid - if they check vaccine status they can fly anyone in without worry about restrictions. So it makes business sense.

It is all about rates, not binary can/cannot statements. An non-symptomatic person can indeed spread the virus, but someone with a fever who is coughing constantly (ie a symptomatic case) will spread exponentially more virus. So a vaccine that prevents such symptoms can in practice reduce infection probabilities. Bring those probabilities low enough and spread stops.

For that final batch of 5-10% of people, today's headlines from the Moderna data dump shows that its vaccine is 100% effective (so far) in preventing serious disease to those that have been vaccinated. And 100% effective in preventing death (there were deaths in the placebo group).

>With this being the case, how does it even make sense for companies like Ticketmaster and Quantas to announce that they'll require their customers to be vaccinated?

This is such a weird take imo. There is no need to vaccine non-risk people afaik. I thought the whole deal with covid is how mild it is for the general population but deadly for a subset of it.

you can't completely predict who it's going to be mild for. 14-year olds with no known underlying issues have died, 25-year olds have lost their sense of smell and taste permanently or suffer from long covid months later.

Not to take away from the argument that we should vaccinate everyone (we should, at least adults. not sure if this vaccine will be approved for kids, which usually requires more stringent approvals), but your argument isn't a good one.

Covid has killed 42 people from age 5-14 in the US according to the CDC, for example. That alone is really not something we should be making huge policy decisions around. It's sad, of course, but it's extremely isolated. All it does is distract us from making good policy decisions.

If I was making policy decisions I'd order vaccine rollout as follows:

Essential workers => 80+ years old => 70+ => 60+ => etc. as we produce and distribute the vaccines.

At some point we might look at the data and say "that's good enough, we can resume normal activities while we work to vaccinate the rest of the population".

Oh, I'm with you that vaccines should be triaged by risk factors, and that reopening should be guided both by % of high-risk population vaccinated and case statistics. I was responding to OP's assertion that we shouldn't bother to vaccinate "healthy" people at all.

IIRC the IFR is ~0.2% for people in the 20-39 age bracket. I still find that risky (though I'm risk-averse), but the better argument is the lingering effects of moderate/severe cases, which I'm not sure is counted.

Also, I assume your policy decision would include younger people with risk factors like heart disease and diabetes, rather than going strictly by age. I'm chronically ill and I want my vaccine.

Sure, throw in risk factors. My lack of completeness is why I shouldn't be the one creating this policy :)

My main point is that there are sub-populations that have a small enough risk that we shouldn't stress over them too much. And talking about them is a distraction.

I would expect that reopenings wouldn't be based on vaccinated percentage, but caseloads, just as they are now. Once more people are vaccinated, however, those will decrease.

>Not to take away from the argument that we should vaccinate everyone.

I'm not sure if this is a concession for argument's sake, but imo it does take away from it. Why do you think it doesn't?

It doesn't take away from it because it's never been a good argument. x - 0 still equals x.

There are plenty of valid arguments to vaccinate everyone we can.

I'm not sure what you mean by x-0, but if there is no risk for young healthy people, then they don't need the vaccine? I understand there are other arguments to be had but this 100% invalidates at least on of them

EDIT: After re-reading I understood the sentence, my bad.

I replied to your comment on a slibling if you want to enlighten me on the subject

We don't know a priori who will have very adverse reactions. Comorbities and old age increase your chances, but those are categorically not the only variables at play.

I'll admit I'm not super well informed on covid, so my opinion on this is weakly held, but isnt that an insanely small percentage of people?

I was under the impression that vaccine + immunity will just lead to herd immunity and the disease to go away on its own.

US population: ~330 million people

Confirmed cases: 13.4 million people

Confirmed deaths: 267 thousand people

deaths / confirmed: ~2%

2% of the US dead (assumes homogeneous 2% death rate, which is incorrect but an upper bound): 6.6 million people

Distribution of deaths by age bracket, including population distribution: https://www.cdc.gov/nchs/nvss/vsrr/covid_weekly/index.htm

About half the population is over ~45 years old.

Anything we do now to reduce the R0 of this disease will disproportionally enable people to live long enough for herd immunity to be attained, courtesy of the exponential growth curve. The amount of people that has to get sick to overwhelm hospitals is smaller than you might think. When hospitals get overwhelmed people die of other preventable cases due to reduced resources, tired physicians, lack of time to see patients at all and people being scared of even going to the hospital in the first place. Old people are not "disposable" and for younger people that happen to have the genetic (or other) predisposition to bad or fatal cases it will be hard to tell them "sucks to be you" when the preventive steps are well understood by now: interact with people as little as possible and when you do, do so outside while wearing masks.

Also, the death rate among poorer people is a multiple of that of the general population, among other reasons because they are working essential jobs to not starve. Those of us that can isolate and don't are saying that these people's lives (essential workers, including health care workers) have no value, they are just meat for the meat grinder.

You appear to have confused case fatality rate with infection fatality rate. There have been far more infections than confirmed cases because most never get tested or formally diagnosed. The actual IFR is under 1%.

https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scena...

That comment was meant to answer two people at once, my bad.

I was referring to the proportion of population that was not at risk. That population has an insanely small chance of having long term side effects from data I've seen. Which was the reason I'm not sure why we would force them to get these vaccines.

EDIT: To be more precise; Of course we want a vaccine and vulnerable people to get it. You'd rather risk getting whatever potential side effects of that vaccine than get covid. I'm more torn about why healthy young people should get it.

> I'm more torn about why healthy young people should get it.

So they don't infect and kill their older relatives.

But those would get the vaccine first, no?

Maybe. Not everyone can get the vaccine. We don't know yet if the vaccine is 100% effective (although it does look very good).

>Not everyone can get the vaccine.

But the proportion of people who are both at risk and can't get the vaccine (and alternatives) must be small (from intuitive maths, I actually haven't looked into this).

Why would this vaccine be mandatory while plenty of other aren't? E.g. I've never got flu-tested before a concert/the flu shot, even though it could pass to other people/kill people.

I'm wondering where's the line between freedom to one own's body and other people's well being. IMO it's not as clear-cut as people make it out to be.

You've mentioned "Low risk" a few times. You're right, the risk for young people is low. That doesn't mean no-risk though. There are plenty of examples of young people suffering harm because of covid.

A TIA at 23 isn't a trivial thing. https://twitter.com/RileyBehrens/status/1333230792206553089?...

At the moment we think covid is at least ten times more lethal than flu. If you're comparing numbers of people killed you need to make sure you're counting death the same way, and most people aren't doing that.

It is possible, but from my understanding, a lot of diseases can have extreme cases. And even so, being free to take on that risk is what I'm refering in when I talk about one own's body.

From https://www.goodrx.com/blog/flu-vs-coronavirus-mortality-and...

          2017-2018 Flu  2018-2019 Flu  COVID-19 as of August 27, 2020
  Cases   45 million     35 million     5 million
  Deaths  61,000         34,157         180,000+

Further reading on how the flu and COVID-19 differ: https://www.cdc.gov/flu/season/faq-flu-season-2020-2021.htm

You're missing my point. These deaths will be insanely reduced once we get the vaccine out to the people that need it. I wasn't saying they are the same; i was saying they are similar in the way they are infectuous and we don't seem to be doing much for young people for most other diseases.

There are also some people who cannot be vaccinated. So getting enough of the population vaccinated to reach herd immunity protects those people too.

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