The best way to prevent health problems is to wash your hands. In space conditions it is challenging to be clean and using the liquid soap with water in space is uncomfortable and takes a lot of time. Which is why I think a foaming soap dispenser is a better solution. First, you wash your hands with a wet towel, then apply some foam, afterwards wipe out with a wet towel again. The object consists of an upper liquid soap tank, where you put a bag with liquid soap, a lower foam tank with foam pump and a wall plate.