Gavin has turned in to a Trump supporter through all this ...Good point but it is as much a case of ethics if you kill someone doing that. Research like this on live humans who are healthy is very tricky. Now when you have people who are pretty ill or very ill who will probably die like with cancer patients then it is easier to get experimental trials permitted. Smallpox was one of the first deadly diseases where they used a sharp lancet needle with virus on it to slightly cut a person's arm and introduce the virus to promote immunity.
But the story with smallpox is interesting in that the Doctor Jenner who did the smallpox vaccination first noticed that milk maids who milked the cows did not catch smallpox which is pretty infectious or the maids got a minor case of smallpox. Not sure if cows showed cowpox but basically Jenner thought the maids were getting an immunity from the cows. Jenner would take puss from a sore on a maid and cut it into well people and they were immune. it was much later that cowpox and smallpox were identified as viruses in the same family of viruses.
I am sure researchers are trying to used killed covid 19 virus or weakened, attenuated virus as the two main ways a vaccine is created.
I said at one time I wondered how many people who thought they were really healthy would choose to get a light exposure of covid to so called 'get it over with". I would like to get it over with getting the virus but man that 15-20 of people who get it bad or die does not sound like good odds.