when my dd got the outbreak on her bum and back of her knees she was desperately unhappy at school and they were gone when she left that school for good.
I expect being unhappy lowered her resistance and that's why she caught the virus in the first place. I don't know for sure but that's my guess, so I'd imagine anything that strengthens your immune system would help prevent you catching them, maybe help your body fight the virus
Some nice cures on that list though