(CNN)Some recent visitors to Disneyland left the fabled theme park with a souvenir they won't soon forget: measles. Public health officials in California and Utah confirmed nine cases Wednesday, all of them visitors of either Disneyland or Disney California Adventure Park in Anaheim between December 15 and December 20. The California Department of Public Health said it suspects an additional three cases but had not yet confirmed those diagnoses. According to the CDC, measles is respiratory disease caused by a virus and spread through the air. It was considered eradicated in the United States in 2000, though 2014 saw a record-breaking number of confirmed cases: 610 according to the Centers for Disease Control, "the highest number of cases since measles elimination was documented in the U.S. in 2000," the CDC says on its website.
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Nine visitors to Disneyland or Disney California Adventure Park have been infected with measles
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The people with measles hail from California and Utah
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They visited the theme park between December 15 and December 20
"Disney and other theme parks in @placeholder are international attractions and visitors come from many parts of the world, including those where measles is endemic."