You wrote “I also haven’t had any reduction at all in the number of colds and influenza bouts I have had.”
I’ve been taking Zinc Picolinate, Quercetin, Vit D3, Vit C, Melatonin, and NAC for two years now and have not had a single respiratory infection. Zero colds and zero influenza. I normally got one to two colds per year. Three years ago, I had a very serious bout of walking pneumonia that I thought was going to kill me.
I added Nigella Sativa a few months back based on the FLCCC I-MASK+ protocol recommendation.
If I DO feel a sore throat starting, I hit it with a povidone iodine gargle and nasal mist. That has knocked out several incipient sore throats (which were always the first sign of a cold coming on).
COVID-19 may have allowed us to discover a cure for many common colds.