This interactive map maintained by the Council on Foreign Relations plots disease outbreaks around the world that have occurred over the past three years. Note some of the largest dots on the US map are from a whooping cough (pertussis) outbreak in California in 2010 — the worst the state had seen in more than 60 years. New outbreaks of old diseases are appearing throughout the United States.
The Portland Tribune: Religious exemptions tilt immunization’s balance, Feb. 16, 2010
Reuters: Indiana has 13 cases of measles as vaccinations decline, Feb. 15, 2012