Personal Belief Exemptions (PBEs) and Schools: School Characteristics and Patterns of Vaccines Exempted in a Stratified Sample of Schools, San Diego California, 2007-08

Background:
Personal Beliefs Exemptions (PBEs) have increased throughout California and San Diego County over the past four years, bringing increased potential for vaccine-preventable disease outbreaks in schools. Public health professionals need to understand in which schools and/or communities PBEs are occurring at higher rates, which vaccines are being exempted, and socioeconomic status (SES) of families opting for exemptions.

Objectives:
To identify schools and SES of parents with under-vaccinated children who have signed PBEs.

Methods:
Thirty-nine (39) schools in San Diego County participated in an audit of California School Immunization Records (CSIRs) of Kindergarten and fifth-grade students. The schools were randomly selected based on the seven Major Statistical Areas and divided into four categories of PBE rate; low, middle, high, and extreme. Audit data included a review of vaccines that were exempted. Schools were profiled on race/ethnicity and free/reduced lunch enrollment (SES indicator). Results of the audit were compared across the four categories of PBE rate and grade level.

Results:
PBE rates were significantly higher among Kindergarteners compared to fifth graders at the same school. Seventy nine percent (79%) of 280 PBEs exempted all vaccines, as documented by a blank CSIR. Varicella was the most exempted vaccine among fifth graders who selectively exempted vaccines (10%). Schools in the “high” and “extreme” categories had a majority White population. The PBE rate was inversely related to the percentage of free/reduced lunch participants at a school.

Conclusions:
Baseline information from this audit can be used to raise awareness within schools about the importance of detailed documentation, tracking under-vaccinated students, and training for school staff. Data gathered will also inform targeted campaigns to schools and neighborhoods and support a more efficient response to outbreak situations. More research is necessary about why people choose PBEs, e.g. clarifying the difference between convenience and personal beliefs.