Well, I assume the challenge trial would be done to test efficacy after you've tested safety. Is this aspect substantially different than with any other vaccine trial?

The difference is right now healthcare facilities and providers are overloaded, so if there are adverse effects of a trial that require treatment, people could end up dead. Normally you would have hospitals ready to handle such cases, but there's zero guarantee of that today.

I'm sure we can all agree that trials with the potential to require medical intervention shouldn't take place in areas with overloaded hospitals. But most areas of most countries don't have overloaded hospitals right now.

All phases will be testing for safety to varying degrees.

So... a challenge trial at phase III will still have risks. Right now, I don’t think we have any vaccines ready to enter phase III?

COVID19 does seem to be actively spreading in the population currently. So I don’t think there would be an issue finding participants for a phase III trial.

At the point that we’re ready for phase III trials. If there is no population where COVID19 is actively spreading, perhaps challenge trials could be considered?

How do you test vaccine safety in a month? Shouldn't we be concerned with long term effects too?

Yea. I'm not an antivax person. I got my meningitis shot in Uni, tool all the ones I needed when going overseas like Typhoid ... but I know about Vioxx and I am weary of stuff rushed to market. I'm not in a high risk group, so I would want to wait a year or two personally.

I realize for many that won't be an option. But with the way things are going in America right now, I'm afraid it might not be an option for anyone; it may be a requirement just to get a job or go to school. That frightens me.

Long term, vioxx has actually been somewhat vindicated as all other nsaids have been shown to cause equal rates of heart attacks. That is, your ibuprofen is just as dangerous, but no one is demanding it be recalled.

Yes. Last time we rushed a vaccine during a pandemic we got pandemrix.

That was approved in Europe but not the US.

1 in 55000 people who took pandemrix got narcolepsy.

The risk is small, but the outcome is a severe debilitating illness that requires constant care for the rest of their life.

We may decide that risk is acceptable, but we need to know about it.

Thanks for the reference. Reading the wikipedia article on the topic, I get the impression that side effects that develop slowly (e.g. more than 3 months post vaccination as in this case) will either not be detected at all or it will be almost impossible to attribute them to the particular vaccine (esp. if you get a different one each year). What is really bothering me is the overall "debuggability" of the vaccines/medication. I mean, people developing them simply have no clue about the different mechanisms by which they can cause harm to the body. Let alone any adverse effect when combined with e.g. over the counter drugs or supplements.