Chemoprevention (also chemoprophylaxis) refers to the administration of a medication for the purpose of preventing disease or infection. Which would include hydroxychloroquine and ivermectin. Are there any others that are being talked about?
The FLCCC has quercetin, vit. C, vit. D, and melatonin listed in their “prevention” protocol, along with ivermectin.
As far as I know, the only real evidence that shows a strong pre-exposure prophylactic effect is for HCQ and ivermectin, with ivermectin having a stronger effect.
There have been a couple of studies, mostly from Spain, showing a correlation between vitamin D deficiency and disease progression, but that’s not really prophylaxis.
Of course, there were the observations by practicing psychiatrists in the US and France that patients on SSRI’s were not contracting the virus, which lead to the now-famous JAMA report last November showing that fluvoxamine is a potent early-stage treatment. But unless one needs an SSRI for other reasons, taking one as prophylaxis would have unacceptable side effects. Whereas a course of low-dose Luvox for 14 days isn’t long enough for psychological effects to present. Bit of a digression that.