A measles outbreak in California that began at Disneyland prompted warnings about potential exposure at theme parks and airports, and reawakened concerns that an anti- vaccination movement may help fuel the spread of the disease.
Of the 59 confirmed cases of measles in California since December, 42 have been linked to an initial exposure at Disneyland, including five employees, according to the state’s Department of Public Health. Officials are urging people to get their shots, and in Orange County, where the theme park is located, the school district may bar students who aren’t vaccinated and may have been exposed.
“The best way to prevent measles and its spread is to get vaccinated,” Ron Chapman, director of the California Department of Public Health, said in a statement yesterday.
Of the 34 measles patients whose medical histories are known, 28 were unvaccinated, the health department said. An increasing number of parents are choosing not to vaccinate their children or delay their shots, citing concerns about other health risks, with large numbers of underimmunized children appearing in some California communities.
Measles is a highly contagious, airborne disease. Victims develop a fever, runny nose and a rash. About one in 20 children with measles catch pneumonia and a small number develop encephalitis, according to the U.S. Centers of Disease Control and Prevention. In some cases it is fatal.
U.S. Outbreaks
The disease has been largely eliminated in the U.S., although it is occasionally brought into the country by tourists or Americans who catch it abroad. In 2014, there were 644 cases amid 23 outbreaks, the most since at least 2000, according to the CDC.
People with measles symptoms who have recently been to areas where international visitors congregate -- such as airports and theme parks -- should “be considered to have a plausible exposure” to the disease, the state health department said.
Resistance to vaccination is more prevalent in some communities. A study of 154,424 children covered by Kaiser Permanente in Northern California found five geographic clusters where children were significantly more likely to be underimmunized by their third birthday, including almost 1 in 4 toddlers in part of Vallejo, a city in the San Francisco Bay area.
The number of children who aren’t getting the recommended vaccines, or receiving them on time, is on the rise, according to the study, published in the journal Pediatrics.
The CDC recommends immunizations for hepatitis, measles, mumps, rubella, polio, tetanus and other infectious diseases, requiring at least 17 injections by age 3.
Officials at Burbank, California-based Disney didn’t respond to e-mailed requests for comment outside of normal business hours. Disneyland and the Disney California Adventure Park are in Anaheim.
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