MINNEAPOLIS (AP) - A national immunization survey shows Minnesota has become less vigilant about vaccinating its children.

The federal National Immunization Survey shows Minnesota has dropped 13 spots in two years - from seventh in 2007 to 20th in 2009 for the primary series of shots given children age 19 months to 35 months.

Children's Hospitals and Clinics of Minnesota says the survey found Minnesota's childhood immunization rate dropped to about 77 percent in 2009 from 80 percent in 2007.

For every percentage point decline in the immunization rate, more than 4,200 children are exposed to diseases that can be prevented by vaccinations.

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