Measles could become endemic in the United States if routine childhood vaccination rates continue to decline, with up to 51 million illnesses over a 25-year period, according to a new study.

Measles, once virtually wiped out in the United States, could become commonplace again if declining vaccination rates continue, a new model shows.

Measles could be well positioned for a comeback in the United States in a very short period of time. If immunization rates continue to drop for a prolonged period of time, the US could see millions of measles cases over the next 25 years.