I guess the same as in diseases like tuberculosis. I’ve just read an article where they studied immune responses in recent TB infections. The authors recruited

I guess the same as in diseases like tuberculosis. I’ve just read an article where they studied immune responses in recent TB infections. The authors recruited subjects from South Africa. I think it’s not that hard to get them to join the trials since payout can be quite significant where such disease are widespread, especially compared to Europe or North America. And some areas have just outrageous HIV prevalence. Just sample a hundred people and you get a decent sample size.