[powersnail]

I'm not a medicine professional, so I'm just curious here.

Since variolation has basically the same principle as vaccination, it's hardly an alternative to vaccination. Is it really worth trying?

To me (with my very crude understanding), proposing variolation as an alternative to vaccination is akin to proposing knife without a handle as an alternative to a regular knife.

Is there any case where vaccination fails to work, while variolation succeed?

[frank2]

A vaccine is months or years away whereas variolation can be deployed right now.

[powersnail]

To deploy it, wouldn't it need to be tested just like a vaccine? Or is it suggested to just deploy virolation without testing?

[frank2]

>is it suggested to just deploy [variolation] without testing?

Yes: the blog post by economist Robin Hanson suggested deploying it without waiting for the results of testing. (Of course, it would be good to test as fast and as much as possible concurrent with the deployment.)

"deploying it": making available to the public a variolation service or procedure designed by medical experts.

[vikramkr]

If we're lowering the standard, why only lower it for inoculation? We can just start deploying the dozen+ vaccines we have in development too if we decide testing isn't important.

[ggreer]

I'm pretty sure Robin Hanson would want challenge trials with experimental vaccines as well. The issue is that authorities won't allow such trials, not that there is a lack of willing medical experts or volunteers.

Though vaccine trials aren't quite as safe for the public as variolation. If a vaccine doesn't work, the person can spread the disease. If variolation doesn't work, then it has the same mortality as natural infection, but afterwards the person is immune and can't spread the disease.

[janekm]

The reason a vaccine is months or years away is only because we are testing whether it is safe enough to give to billions of people. The reason we do that is because a virus can cause disease both directly but also in unexpected ways (e.g. by immune over-reaction to some of the viral RNA in some individuals). Variolation as a public policy would have to go through the same safety testing for the same reasons (as it is a form of vaccination with un-weakened virus). You would also still have to produce doses of the variolate, both in terms of replicating the virus and bottling it.

There is no real time advantage to variolation. Anybody making the case for variolation without validation would be better off making the case for vaccination with one or several of the 30 vaccine candidates under study for SARS-Cov-2 right now (a case could be made... allow volunteers to be given the candidate vaccine of their choice in larger numbers than normal clinical trials, scaling up as the risk profile of each candidate vaccine is known).

[frank2]

I am not an expert (but neither are you, I am guessing).

>Anybody making the case for variolation without validation would be better off making the case for vaccination with one or several of the 30 vaccine candidates under study for SARS-Cov-2 right now

The advantage variolation has over the 30 vaccine candidates, I am guessing if the question is what to do before the results of testing are available is that most of those 30 candidates will turn out after being tested to fail to confer significant immunity.

I believe that the fate of most vaccine candidates for any disease is that testing reveals that the candidate fails to confer immunity to most or all of the people it is given to. Also I believe that it usually takes at least a year to produce enough of a vaccine to test, then test, then analyze the results of the testing.

[vikramkr]

Variolation could fail as well. It would still need to be tested for safety and efficacy.

[Matticus_Rex]

Tested for safety? We know what it does. It gives a low dose of the virus. If we know most people will get it anyway, then we don't need to know more than that in terms of either safety or efficacy.

[vikramkr]

A low dose could trigger an incomplete immune response leading to antibody dependent enhancement (ADE) on exposure to the virus in the future. Other Coronavirus are known to have that characteristic, we dont know if this strain does. Safety is making sure that we aren't priming people to get worse versions of the disease like what unfortunately happened with dengue.

https://www.pnas.org/content/117/15/8218

https://en.m.wikipedia.org/wiki/Dengvaxia_controversy

[BurningFrog]

The point you're missing is that there is no vaccine for Covid-19.

If there was, no one would consider variolation.

[janekm]

There are 30 candidate vaccines (probably a lot more by now). 32 if you include the two that are non-weakened forms of virus that are being proposed for variolation.

[pmayrgundter]

Are these 2 others actual registered trials? Or are you referring to public proposals for such, like Hanson's?

I'm working on just such a public proposal [1] and have been in correspondence with Hanson but haven't heard of any registered.

[1] "SARS-CoV2 Live Virus Skin Vaccine" - https://tinyurl.com/y8ujrcze

[bradj]

Having "candidate vaccines" is very different from having a "vaccine". Variolation is a reasonable alternative to the lack of a known, effective vaccine.

[vikramkr]

Variolation as a term only applies to smallpox. Giving small doses of the live virus as hanson suggests is literally just a lame vaccine. It's also not known to be safe or effective and would have to go through all the trials anyway.

[ggreer]

Hanson is saying we should do those trials, not that we should start deliberately infecting the masses ASAP. The issue is that such trials are banned.

[vikramkr]

You have to test variolation too. There are dozens of vaccine candidates, if we are willing to ignore safety and efficacy testing we can start vaccinating people today.

[emiliobumachar]

This is a key insight. All of the benefits of variolation today skipping tests can be had by vaccination today skipping tests.

[ggreer]

Not entirely accurate. We know variolation will provide immunity. The main risk is to the volunteer, not to others. A vaccine might not provide immunity. That would make the patient a vector for the disease and endanger others.

[emiliobumachar]

> We know variolation will provide immunity.

Do we really? I don't keep up with the news, did we already dismiss those reports about re-infection? Does it last long enough to be globally useful?

> The main risk is to the volunteer, not to others.

The main risk, sure, but the volunteer will become infectious. Vaccines constrain the risk to volunteers a lot better.

[ggreer]

> Do we really? I don't keep up with the news, did we already dismiss those reports about re-infection? Does it last long enough to be globally useful?

It seems to be extremely rare, and it's hard to know how many of those cases are due to incorrect initial diagnosis or people with odd immune systems. Immunity seems to be much greater than that conveyed by vaccines (which protect 85-95% of recipients).

> The main risk, sure, but the volunteer will become infectious. Vaccines constrain the risk to volunteers a lot better.

In vaccine challenge trials, people are exposed to the virus and kept quarantined until after the incubation period. Those who aren't protected by the vaccine must remain quarantined until their immune system defeats the disease. It would be the same for deliberate infection. Volunteers wouldn't be allowed to leave until the virus is no longer detectable. Hanson makes this clear in his blog post (linked to at the top of this thread).

That said, most vaccine trials are not challenge trials. Researchers give patients the vaccine and wait a while to see how many of them naturally contract the disease. During that time, the patients may or may not have immunity and can potentially infect others.

[BurningFrog]

Right. I think the proposal is simply to actually test variolation.