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Orange County faces biggest measles outbreak in California

A person infected with measles is shown in this undated file photo.

March 26, 2014 8:41:45 AM PDT
Orange County health officials are warning residents of the biggest outbreak of measles in California.

This year, 21 people in Orange County have been diagnosed with the highly contagious respiratory disease and seven have been hospitalized. In a typical year, Orange County has no reported cases of measles.

The Orange County Health Department held an emergency meeting Tuesday night to discuss the unexpected outbreak and encourage residents to get vaccinated. The vaccine is 99 percent effective after two doses.

Neighboring counties, such as Riverside and Los Angeles, have also seen a spike in cases.