CDC Reports High Vaccination Coverage Among Children Entering Kindergarten

A new report from the Centers for Disease Control and Prevention (CDC) shows that while vaccination coverage remains high among children entering kindergarten, exemptions are keeping some states below immunization program targets.

Vaccination requirements for school-aged children are set on a state and local level to prevent the spread of several diseases, including whooping cough, chickenpox, mumps, polio, measles, hepatitis A, among others. In the United States, where outbreaks of vaccine-preventable diseases are now uncommon, the CDC recommends a schedule of immunizations for 14 diseases in children ages 4 to 6 who are beginning school. Students in all states are allowed medical exemptions from vaccination if a child has a health condition that prevents them from receiving a vaccine, and all but two states allow for nonmedical exemptions from vaccination for philosophical or religious reasons. However, a study published earlier this year emphasized the public health consequences of skipping vaccines, with researchers finding that a 5% drop in measles, mumps, rubella (MMR) vaccine coverage would lead to three times more measles cases among children ages 2 to 11 in the United States.

In a new report published in a recent volume of the CDC’s Morbidity and Mortality Weekly Report, researchers looked at vaccination coverage and exemption rates for selected vaccines among kindergarteners during the 2016-2017 school year in the United States, including the District of Columbia. The authors note that the Advisory Committee on Immunization Practices recommends that children who are 4 to 6 years old and starting kindergarten receive 5 doses of diphtheria, tetanus, and acellular pertussis vaccine (DTaP), 2 doses of measles, mumps, and rubella vaccine (MMR), and 2 doses of varicella vaccine, among other immunizations. The report included data collected from 49 states pertaining to required vaccinations among public and private school kindergarteners, as well as exemptions from public schools in 50 states and exemptions from private schools in 49 states. In total, the report included vaccination coverage for about 3,973,172 kindergartners, exemption data for 3,666,870, and provisional or grace period data for 2,463,131.

For the school year, the researchers found that median vaccination coverage was 94.5% for the required number of doses of DTaP, 94.0% for 2 doses of MMR, and 93.8% for 2 doses of varicella vaccine. A median of 2% of kindergartners had an exemption from at least one vaccine, which was similar to the previous school year’s exemption percentage of 1.9%, while 2% of students had a provisional enrollment or grace period that allowed them to attend school while catching up on missing vaccinations. Notable in the report, Alaska, Colorado, Idaho, Indiana, Kansas, and DC reported MMR vaccine coverage of less than 90%, and DTaP vaccine coverage was also less than 90% in Alaska, Arkansas, Colorado, Idaho, Kansas, and DC. California, New York, North Dakota, and Tennessee saw increased coverage for all reported vaccines.

Significant for public health, the report notes that the number of states sharing local-level school vaccination coverage increased from 25 to 30, contributing to transparency and giving communities more information on vaccine-preventable diseases. “Because vaccination coverage and exemption levels are clustered locally, availability of local-level vaccination data can help immunization programs identify schools that might be vulnerable in an outbreak,” write the authors, noting that improved data collection helps health officials understand factors contributing to undervaccination and how to improve vaccine coverage.