As the Disneyland measles outbreak grows, officials say it's part of a larger battle against the disease.
Measles has become a growing concern among California health officials. Before the December cases, 2014 was already the worst year for measles cases in California in nearly two decades.
The rise of these diseases come as a smaller percentage of California's kindergartners are getting a full set of immunizations by the time they enter school. In 2002, more than 95% of kindergartners in California were fully vaccinated for measles and whooping cough; now, the number is about 92% — low enough to promote the spread of these highly infectious diseases.
Authorities believe people were exposed to measles at Disneyland or Disney California Adventure between Dec. 15 and 20.
The disease, rare in the United States but highly contagious and potentially serious, has now infected at least eight people in Orange County and more than a dozen statewide.
It causes fever, rash, coughing and red, watery eyes. Those infected are contagious from about four days before the rash appears through four days after.
In the original six cases, three were unvaccinated children -- all old enough to be vaccinated -- who contracted measles at Disneyland, said Orange County Health Care Agency spokeswoman Nicole Stanfield.
Three others are adults; one was unvaccinated, one was partially vaccinated and one was fully vaccinated. None of the adults was hospitalized, Stanfield said.
Officials stressed that the best way to prevent infection is to get vaccinated. Children should get their first vaccination between 12 and 15 months of age, with a second dose between 4 and 6 years old before going to school, they said.