Someone I know lost the ability to sense many organosulfur compounds after having Covid. Garlic is tasteless/smell-less mass, rotten eggs don't smell like anyth

Someone I know lost the ability to sense many organosulfur compounds after having Covid. Garlic is tasteless/smell-less mass, rotten eggs don't smell like anything. I don't think I've ever heard of sinus infections of any kind causing that kind of change for going on 3 years. That's pretty weird considering how sensitive humans are to organosulfur compounds.