MARTINEZ, Calif. (KGO) -- Measles cases have topped 700 this year, the highest level in the United States since the disease was declared eliminated in 2000.
Contra Costa County health officials say fortunately there have not been any cases in the county this year. They're encouraging adults who aren't sure if they've had a second round to get one.
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The measles, mumps and rubella vaccine needs to be stored in a refrigerator or freezer to maintain it's effectiveness. In Contra Costa County, there are extra doses on hand outside
of the clinics.
"It's very alarming," said Contra Costa County Health Officer Dr. Chris Farnitano.
Farnitano is encouraging parents to make sure their children are vaccinated at the one-year-old mark and again at five-years-old.
"The measles vaccine is very safe, it's very effective and it's very important," said Farnitano.
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For international travel with infants, Farnitano says health officials recommend an extra dose between six months and a year. That's in addition to the two later on.
Since two doses weren't always the standard, adults who aren't certain they received a second dose as a child are encouraged to get one now as an adult.
"If you're not sure you can always get an extra dose there's no harm in getting an extra dose," said Farnitano.
As Los Angeles contends with an outbreak, university students who may have been exposed and are uncertain if they've been vaccinated are being asked to quarantine themselves.
A UCLA Spokesperson says there are 27 students quarantined, one on campus and 26 self-isolating in residences off campus.
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A person with measles can spread the disease to others even before they have any symptoms. Symptoms generally appear seven to 14 days after a person is infected and typically begin with a high fever, cough, runny nose and watery eyes. Three to five days after symptoms begin a rash breaks out.
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Measles cases top 700 this year in the United States