Silver is an age-old remedy for infections. As soon as I feel a tickle in my throat, I spray some into my mouth or nostrils. Bacteria are unlikely to develop resistance to it, like they do to antibiotics. (A bottle may cost about $12.)
I like to be prepared with a stash of healthy food in case my energy dips. Sacha inchi seeds, also known as Inca peanuts, are loaded with omega-3s, protein, and fiber. (Available at health food stores.)
For those times when hand washing just isn't possible.