micro, That may be correct. I won't take a vaccine, if they develop one. I've never been against vaccines, but for now, this is the ONLY one, I'm against.
Our local teaching hospital, in conjunction with the University medical department, and their research department, has done studies, and are confirming the hydroxychloroquine/azithromycin combo works. They're the ones doing the antibody testing too.
While immunity, and/or longevity of the antibodies will be studied, that is not the purpose of the testing, at this time. Once you get it, from what they can tell, the antibodies can provide up to a couple months, or longer of protection. It may be longer, even if depleted, but that's not what the study is about, nor has longevity been determined yet. The study is looking for recently recovered patients, that the antibody count is very high. They can then extract the antibodies from the plasma, and use it in a serum, to help those at high risk from getting it, or at the very least, it will greatly minimize the symptoms.