Measles outbreak centered in California, even the vaccinated are getting sick

A measles outbreak that originated in Disneyland has climbed to 78 cases as the virus continues to spread.

California health officials reported Friday that nearly 90 percent of the infections are in California. Forty-eight cases in the state are directly linked to visits to Disney parks or contact with someone who went there.

Measles has also been confirmed in six other states -- Utah, Washington, Colorado, Oregon, Nebraska and Arizona -- and Mexico.

The highly contagious illness, which has been eliminated in the U.S., can enter the country from abroad where measles is still a problem. Symptoms include fever, cough, runny nose and a telltale rash.

Health officials have urged people to get vaccinated against measles.

But the problem is that at least five cases in California involve people who had their shots.

Experts say this is because the vaccination isn't 100 percent effective, especially if people have only had one shot, as was the case before federal guidelines changed in 1989.

The failure rate is 5 percent among those who had one shot and under 1 percent after two.

"When you have a scenario where hundreds of people get exposed, then even if the vaccine is 99 percent good after two doses, you're going to have a handful of people who are going to get sick," an Orange County public health officer explains.

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