Vaccine Decision Making in a Vaccine-Hesitant Community — Marin County, California, 2013-2014

Wednesday, June 17, 2015: 2:00 PM
103, Hynes Convention Center
Jasmine Carver , County of Marin, San Rafael, CA
Jessica Cunningham-Krahl , County of Marin, San Rafael, CA
Karina Arambula , County of Marin, San Rafael, CA
Sharayn Forkel , County of Marin, San Rafael, CA
Rochelle Ereman , County of Marin, San Rafael, CA
Matthew Willis , County of Marin, San Rafael, CA

BACKGROUND:   California Personal Belief Exemptions (PBEs) are non-medical exemptions from school immunization requirements.  Marin County, an affluent county in the San Francisco Bay Area with a population of approximately 256,000 people, has been identified as a vaccine-hesitant community.  The prevalence of PBEs among the 3,000 kindergartners in Marin County increased from 3.7% in 2002 to 7.6% in 2013 and remained higher than the statewide average.   In 2014, California implemented legislation requiring parental conversations with medical professionals before receiving PBEs.  This study explored local vaccine decision-making to equip providers for the conversations required under the new law and assessed changes in the PBE rate. 

METHODS:   The Marin Childhood Vaccination Survey was developed from existing instruments and subject expert feedback.  The survey topics included exemption status, vaccine information sources, and vaccine behaviors and beliefs.  In late 2013, a survey was sent to Marin County school immunization coordinators for distribution.  All kindergarten parents at 40 public and private schools received the survey.  Responses were described using proportions and chi-square tests.  Findings were shared with medical providers and other relevant audiences.  The Marin County kindergarten PBE rate for the 2014/2015 school year was compared with prior years.

RESULTS:   Of 493 respondents, 85% (417) had fully vaccinated children and 8% (39) had PBEs.   More parents with PBEs received vaccine information from complementary and alternative providers compared to parents without PBEs (54% vs. 4%; p < 0.01).   Of kindergartners with PBEs, most had at least one of the school entry vaccines (84%).  Sixty-four percent were up to date with DTaP while 6% met the hepatitis B requirements.  The most common reasons parents requested PBEs were that children get too many vaccines at the same time (100% agreed) and vaccines contain unsafe toxins (62%). Thirty-four percent of parents with PBEs expressed agreement that vaccines can cause autism. Parents also reported inadequate trust in the healthcare system and low perceived risk of certain vaccine-preventable diseases.  We presented study data to pediatricians, public health professionals, local media and the Marin County Immunization Coalition.  In the 2014/2015 school year, the Marin County kindergarten PBE rate decreased to 6.5% (a 14% one-year reduction). 

CONCLUSIONS:   Providers were able to use findings in vaccine-related conversations required under the new law to anticipate themes of parents’ concerns and recognize the diversity of vaccine decision making.  Decreased PBE rates may reflect successful provider-parent communication about vaccines.