Thirteen states have outbreaks, those states include California, Washington, Oregon, California, Texas, Hawaii, Mississippi, Illinois, Wisconsin, Pennsylvania, New York, Rhode Island, Connecticut and New Hampshire.
The state with the most cases is California, so far this year there've been 58 reported cases of measles.
Compare that to last year at this time only four cases.
“The CDC is concerned because measles is probably the most contagious disease that we know of. And a lot of doctors have never even seen a case. So some of the transmissions take place in doctor's offices. Here's what you need to look for in terms of measles. You're going to see a high fever... Red eyes...a hacking cough a rash that starts with dots around the forehead...and it spreads over the entire body,” said Dr. Richard Besser, ABC News Consultant.
Dr. Besser says he believes the outbreak is a result of people traveling around the world and bringing measles home plus the fact that many people are choosing not to vaccinate their children or are delaying vaccinating their children.
Here's what you need to watch out for: high fever, red eyes, a hacking cough and a rash that starts with dots around the forehead and spreads over the entire body.