I like #1. Zundfolge mentioned that on page 1. It really is the best idea because it does not compel or force it. If you're on the gov program you have to meet the gov standard(s).

I think #2 would be hard. For some cases it would be easy to trace but others? Going back to that stat I posed, 12% of CO kindergarteners are not vaccinated (MMR). That's 1 out of every 8. We probably come in contact with these kids often and a lot of that contact is casual; grocery store, parks, church, restaurants, etc...