More Americans have been infected over the first four months of 2014 than have been infected in the first four months of the past 18 years. Health officials said 13 outbreaks and 129 cases have been recorded so far this year.
California is reporting the highest numbers with 58 cases, the CDC said. Many of the cases are the result of people visiting the Philippines, which is experiencing a very large measles outbreak.
The last time there was a reported death from measles in the United States was in 2005, according to the CDC.