CV and mad panic behaviour

[LP]

Define "effective".

One that delivers improved resistance to, immunisation against or limits transmission of Sars-CoV-2 infections in a significant percentage of recipients(> 40%) without any permanent or deleterious unwanted side-effects. An effective vaccine doesn't have to stop you getting Sars-CoV-2, it may stop you spreading the infection while reducing your own symptoms.

The reason for recruiting people to receive deliberate infections isn't to determine if the vaccine is effective or not, it is to reduce the time-frame to a conclusion of the study. There are risks though, that the study isn't properly double blind because they have to know who gets exposed to a live infection.

btw., It looks like the commonly believed concept of a single shot vaccine is dead, that is one shot and you're safe for life isn't going to happen, because there are significant numbers of re-infections appearing now in US and European hot zones. At this stage it's not clear if the second infection is better, worse or the same, it'll take many many more repeat infections before that is known.