BFing is one of the best ways to keep your bubba safe because he's getting all the anti-bodies that you're making via the milk to help him fight it off.
I think you're doing all the right things - frequent handwashing, try not to touch him when you don't have too (hard I know, they're so kissable).
Make sure you look after yourself and get lots of liquids. The gastrolyte stuff from the chemists is a good way to keep your salts and blood sugars up. It might be worth popping down to the Dr if you're feeling so rotten so soon after birthing because gastro and recovering from birth is a big load on your body