WELLFLEET — A large number of children who visit the Outer Cape Health Services clinic here are “under-vaccinated” — having not received a full series of standard immunizations against infectious diseases, which are required under state law for school admission.

Only 77 percent of the kindergartners at the Wellfleet Elementary School in the past three years have been fully immunized against hepatitis B, MMR (measles, mumps, rubella), DTaP (diphtheria, tetanus, pertussis), polio, and varicella (chickenpox), according to the Mass. Bureau of Infectious Disease and Laboratory Sciences. This puts Wellfleet Elementary in the 10th percentile for immunizations statewide.

At Eastham Elementary, the immunization rate is only slightly higher, with 83 percent of kindergartners having received a full series of vaccines.