Measles Outbreak Update February 17, 2015 Measles cases have continued to occur in Orange County with 35 cases confirmed this year. In California, as of February 13, 2015, 113 cases have been confirmed since December 2014; 20% of those with known hospitalization status have been hospitalized. Of those with known vaccination status, the majority are unvaccinated, with most of these because of personal belief exemptions. Orange County Cases Of the 35 Orange County cases, 14 are children, 13 of whom were not vaccinated. Thirteen of our cases spent time at the Disneyland Parks since mid-December, 2014. Sixteen cases had no known source, signaling ongoing transmission in the community. The most recent cases were contacts to previously known cases. Vaccination is Key to Prevention Although some of the confirmed cases occurred in people with a history of vaccination, their illness is generally milder and typically not as infectious. Vaccination is critical to prevent the ongoing spread of disease. Although the overall risk of getting measles in Orange County remains low, residents who have not received any measles-containing vaccine and do not have any other evidence of immunity should get a dose of MMR vaccine. Two doses of measles-containing vaccine (MMR vaccine) are more than 99% effective in preventing measles. The first dose is routinely given at 12-15 months of age, with the second dose usually at age 4-6 years. The second dose may be given any time ≥28 days after the first dose. All healthcare workers (HCW), including those born before 1957, should have two documented doses of MMR or serologic evidence of measles immunity. HCW who are exposed to a case of measles may be excluded from work until they provide evidence of immunity. If exposed to measles, all, children and school/child care staff without documented immunity will be removed from work/school/child care from day 7 after the first exposure to day 21 after the last exposure. Report any suspect case of measles to the Orange County Health Care Agency immediately at 714-834-8180 (714-628-7008 after hours). For more information on measles, see www.ochealthinfo.com/measles . Information on vaccination recommendations by age group is available in the previous advisory dated 1/26/2015 and guidance on clinical presentation, infection control, reporting, and testing is in the 1/21/2015 advisory. click here to download this measles outbreak update.