I have diagnosed OCD and wash my hands lots of times a day. The last time I had a sickness bug was in 2006. Some blood types are immune to certain viruses such as Norovirus (e.g. people with type B blood lack H1-antigen and are resistant to most stomach bugs!) but I have type O blood, which makes me very prone to bugs and used to catch sickness bugs a lot in childhood until my OCD took hold.
I have a theory that people who are naturally not prone to sickness bugs, notice that they rarely get sick so wash their hands less often and then think that the exposure to germs is helping their immune systems in some way and wonder whether this makes any sense?
So just wondering- how often do you wash your hands each day? How often do you get sickness bugs?