ATLANTA, Georgia (CNN) -- Sixty-four cases of measles have been diagnosed in the United States this year, the most in seven years, according to the Center for Disease Control and Prevention.
Measles is a respiratory disease whose familiar symptom is red blotches on the skin.
In all but one of the cases, the people who contracted measles had not been vaccinated. Some were too young to have gotten the shots, which are administered from 12 to 15 months of age.
The CDC released the statistics Thursday to "serve as a reminder that measles can and still does occur in the U.S. Ongoing measles virus transmission was declared eliminated in the U.S. in 2000, but the risk of cases and outbreaks from imported disease remains," the organization said in a news release. 
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In 54 of this year's cases the victims imported the measles from other countries, the CDC said.
Dr. Anne Schuchat, the director of the CDC's National Center for Immunization and Respiratory Diseases, said many of the imported cases came from European nations and Israel. 
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"Many people have forgot about measles in the United States," she said Schuchat at a news conference Thursday. "It is very important for travelers heading off to Europe to make sure their immunizations are up to date."
The cases were reported in nine states, it said, and cases are being treated in Wisconsin, Arizona, Michigan and New York.
Measles is a viral disease that can be deadly if not treated. The 64 patients ranged in age from 5 months to 71 years. Fourteen patients were hospitalized but no deaths were reported. E-mail to a friend 
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