Vitamin D is also a very good thing for respiratory systems and for reducing inflammation.
And exposure to sunlight allows the skin to make vitamin D- win win.
A doctor friend and my brother who’s a PhD microbiologist both told me about “The Vitamin D Hammer”...
If I start to feel something coming on, will try this...
https://vitamindanswers.com/vitamin-d-hammer-beating-the-flu-in-72-hours/