Rest, fluids and more rest!
I try to air the house out a few times a week in winter as we tend to close up with the heater on. I also make food with garlic and lots of veg - chicken soup etc. I also pop disinfectant into the clothes/linen after the kids have been unwell. Similiarly I throw out or sterilise toothbrushes - maybe over kill but at least it makes me feel like I doing something. We try to rug up and hit the park so we can all get some exercise and avoid cabin fever if the kids are up to it.
xxxx