Updated

Health officials say vaccination rates for toddlers remain high, but they are concerned about an overall drop in measles vaccinations.

The Centers for Disease Control and Prevention on Thursday released a report showing vaccination rates for children ages 19 through 35 months, based in part on a 2009 telephone survey of parents of more than 17,000 children. More than 90 percent received most routine vaccines, and more than 99 percent got at least one.

But the rate for the measles-mumps-rubella combination vaccine dropped from 92 percent in 2008 to 90 percent - a concern, given a recent increase in U.S. measles cases. The rate for the vaccine against whooping cough also was down slightly, but health officials believe getting boosters to teens, adults and people who are around infants is a more important way to attack a recent whooping cough outbreak in California.

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