At least 20 confirmed cases of measles have been connected to Disneyland in southern California, doubling the count since last week according to the New York Daily News.
Initially, the outbreak consisted of nine confirmed cases of measles — seven people in California and two in Utah — all of whom had recently visited Disneyland.
Although no additional cases have been reported in Utah since the initial outbreak, confirmed cases of measles have since risen to 16 cases in California, one in Colorado, and one in Washington.
So far, all of the individuals infected with measles visited Disneyland between Dec. 15 and Dec. 20, according to the report.
Disneyland Park in Anaheim, Calif., remains open and has stated that it is working with the California Department of Health in its investigation.
Spokesperson for the California Department of Health Anita Gore told New York Daily News that the department believes the outbreak came from either an international visitor or an American parkgoer returning from an overseas trip.
At least two of the individuals infected with measles were unvaccinated, according to the report. Unsurprisingly, most people who get measles have never been vaccinated for the disease.
In 2014, 610 confirmed cases of the measles reported to the CDC from Jan. 1 to Nov. 29, the highest number of measles cases since measles were eliminated in the U.S. in 2000.
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