Worried health officials say a small but growing proportion of the youngest children in the U.S. have not been vaccinated against any disease.
They say an estimated 100,000 young children have not had a vaccination against any of the 14 diseases for which shots are recommended.
The numbers come from a telephone survey last year of the parents of about 15,000 toddlers. The Centers for Disease Control and Prevention reported the numbers Thursday.
The new estimate is based on finding that 1.3 percent of the children born in 2015 were completely unvaccinated. That's up from the 0.9 percent seen in an earlier assessment of kids born in 2011.
The researchers didn't ask why parents didn't get their kids vaccinated.
Young children are especially vulnerable to complications from vaccine-preventable diseases.
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