What diseases can be transferred from physical contact with somebody that doesn't wash?

I was en route to work when a homeless person asked me for a cigarette. Normally if somebody asks I hand them the pack as to be polite in case they don't want even my clean hands touching something that will be going in their mouth. So I did this also for the beggar without considering what lay on his skin. He reached over with filthy hands and as so touched more than the one butt claimed. It was apparent he hadn't been washing his hands in days if not weeks. What diseases, if any, did this guy possibly pass off to me?