It’s really, really difficult. I was a preschool teacher for a while and oh my god, I was sick constantly despite all precautions. Some of my friends finally asked, Is there ever a time when you’re not sick? and I had to laugh because.. well.. no.
The best thing is to try to teach the kids to wash their hands frequently, the teacher should do the same, and do whatever you can to keep contamination at a minimum. A bottle of bleach water squirted over the desk surfaces can help (kids’ hands = nasty!). I’d also recommend keeping a big bottle of hand sanitizer on her desk.
My mom worked in the herbal supplement industry for 25+ years and what I’ve been told is that echinacea is an immune booster, so it should be taken before you get sick. As my mom said, ‘If you’re sick and your immune system is down, there is nothing to boost.” Goldenseal can be taken once you’re full-on sick. Vitamin C can help a lot with boosting the immune system as well as helping healing.
Some other germophobe-y tricks I’ve picked up.. when someone sneezes, hold your breath for about 10 seconds to let the mist micro-particles settle down, so you don’t inhale sickness germs. Frequent hand washing, of course. Being conscious of where you put your hands (i.e. if it’s cold/flu season and I touch a doorknob, I sanitize/clean my hands) and then where you put your hands (i.e. avoid rubbing mucous membranes such as the eyes, nose, mouth).