The measles outbreak linked to visiting two California Disney theme parks,  Disneyland and Disney California Adventure Park, has grown to 33 cases in four states, according to numbers from the respective health departments.

Image/CDC
Image/CDC

The majority of the current outbreak has been seen in California residents as that number is now 29. The breakdown by jurisdiction is as follows: Alameda (3), Los Angeles (5), Long Beach (2), Orange (10), Pasadena (1), Riverside (2), San Bernardino (2), San Diego (3) and Ventura (1).

In addition, two cases have been reported in Utah and one each in Colorado and Washington.

In El Paso County, Colorado, health authorities say they have identified nearly 300 people who may have been exposed to a patient with measles in Colorado Springs in early January.

Of the more than 250 people contacted to date, El Paso County Public Health has identified a small number of individuals (fewer than 10 people) with high exposure and who do not have proof of immunity. Because of their lack of immunity, these people are at the highest risk of developing the disease and transmitting it to others. As a precaution, Public Health has arranged for these individuals to remain at home for a quarantine period of 21 days after their last exposure to the patient. All individuals are cooperating and have agreed to stay home and be monitored.

Experts say that places like Disneyland, where millions visit annually, are the ideal place to get a measles outbreak started. “This is the ideal scenario,” said pediatric infectious diseases expert James Cherry. People go to Disneyland “from all different counties and all different states.”

The measles virus is transmitted by respiratory droplets from coughing or sneezing, and is so contagious that 90 percent of people in close contact with an infectious person will get the disease if they’re not immunized.

Symptoms of measles include a fever of 101°F or higher, cough, runny nose and a rash that spreads to cover the body. The rash usually occurs within two weeks of exposure.

Two doses of measles-containing vaccine (MMR vaccine) are more than 99 percent effective in preventing measles.

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