The measles is a problem because certain morons refuse to vaccinate because they don't understand science and cling to moronic notions that have been disproven time and again.
Oh and smallpox:
1970s. Outbreaks in India and Yugoslavia. So you want us to stop vaccinating when one of the largest populations on the planet, one that has a regular number of citizens visiting, and living in America, had a bad outbreak in the 70s.
Why don't you provide me with one logical reason to NOT vaccinate.