I mean, bravo to the Amish who went to the Philippines to help. But I wish they would have checked with the CDC (http://goo.gl/heULIj), or the State Department, or many, many places on the Internet about suggested vaccinations before traveling there. Because not only did they put folks in the Philippines at risk, but folks back here in in the US have been harmed.
(Note: hopefully they didn't bring back cases of Hep A or Typhoid, too; presumably Hep B was less of a probability, but I'm wondering if any of them came down with Malaria.)
(h/t +Les Jenkins)
Unvaccinated Amish missionaries create huge Ohio measles outbreak
Some Amish missionaries to the Philippines, who were never vaccinated against the Measles, have helped create the biggest US measles outbreak in 20 years.
Personally, I don't think you should be able to travel without them. It should be recorded on your passport. A few medical exceptions, but I can think of no other. Just like you can refuse to be searched by the TSA, you're still free to refuse vaccination – with the consequences.
Same requirement on receiving a visa, perhaps also on inbound visitors.
I also think that GPs should generally refuse new unvaccinated clients because of the waiting room risk. Schools should require them, period, again – with the few medical exceptions. Private tutoring or home schooling is available.
+Al Hunt There are some countries that require them on admission (in southern Africa we needed to carry proof of vaccination for yellow fever before we could cross some borders). But, yeah, I think that's going to be increasingly important over time, as international mobility continues to increase.