KANSAS CITY, Mo. - Right now, the U.S. has the highest number of measles cases in about 20 years.
The CDC's new report shows more than 300 cases have popped up since January-- most of them in Ohio Amish communities where people are not vaccinated.
The report says travelers bringing the virus into the U.S. are fueling the outbreak.
A local doctor says what's making the fight difficult is that many physicians have never treated measles before.
"It's going to get mistaken for other diseases, especially in children where fever and rash are not uncommon at all. So I think it's going to be hard for doctors to recognize it," Dr. Kevin Ault said.
Dr. Ault said the last measles outbreak in 1996 came after an article linked the measles vaccine with autism. That article has since been debunked.