(ProPublica) – The U.S. eliminated measles a quarter century ago, but to keep its “measles-free” designation, officials will have to make a strong case that measles is not continuously spreading within its borders. Our analysis shows how difficult that could be.

The Texas and Utah cases now sit at the center of an unusually technical — and politically fraught — question: whether the United States will lose its measles-free distinction.

Countries aren’t penalized for losing the status, but it’s an indication of cracks in a nation’s once rock-solid immunization programs, a loss of faith in vaccines among its people — or both. (Read More)