Nonmedical Exemptions to School Immunization Requirements

TLDR

School immunization requirements have been crucial in controlling vaccine‑preventable diseases, yet most U.S. states allow nonmedical exemptions that increase the risk of disease acquisition and transmission. This study aimed to compare nonmedical exemption rates across states offering only religious versus personal belief exemptions, across varying ease of obtaining exemptions, and to assess how these policies relate to pertussis incidence. The authors analyzed state‑level nonmedical exemption rates from 1991‑2004 and pertussis incidence data for those under 18 from 1986‑2004, using multivariate models to adjust for demographics.

Abstract

School immunization requirements have played a major role in controlling vaccine-preventable diseases in the United States. Most states offer nonmedical exemptions to school requirements (religious or personal belief). Exemptors are at increased risk of acquiring and transmitting disease. The role of exemption policies may be especially important for pertussis, which is endemic in the United States.To determine if (1) the rates of nonmedical exemptions differ and have been increasing in states that offer only religious vs personal belief exemptions; (2) the rates of nonmedical exemptions differ and have been increasing in states that have easy vs medium and easy vs difficult processes for obtaining exemptions; and (3) pertussis incidence is associated with policies of granting personal belief exemptions, ease of obtaining exemptions, and acceptance of parental signature as sufficient proof of compliance with school immunization requirements.We analyzed 1991 through 2004 state-level rates of nonmedical exemptions at school entry and 1986 through 2004 pertussis incidence data for individuals aged 18 years or younger.State-level exemption rates and pertussis incidence.From 2001 through 2004, states that permitted personal belief exemptions had higher nonmedical exemption rates than states that offered only religious exemptions, and states that easily granted exemptions had higher nonmedical exemption rates in 2002 through 2003 compared with states with medium and difficult exemption processes. The mean exemption rate increased an average of 6% per year, from 0.99% in 1991 to 2.54% in 2004, among states that offered personal belief exemptions. In states that easily granted exemptions, the rate increased 5% per year, from 1.26% in 1991 to 2.51% in 2004. No statistically significant change was seen in states that offered only religious exemptions or that had medium and difficult exemption processes. In multivariate analyses adjusting for demographics, easier granting of exemptions (incidence rate ratio = 1.53; 95% confidence interval, 1.10-2.14) and availability of personal belief exemptions (incidence rate ratio = 1.48; 95% confidence interval, 1.03-2.13) were associated with increased pertussis incidence.Permitting personal belief exemptions and easily granting exemptions are associated with higher and increasing nonmedical US exemption rates. State policies granting personal belief exemptions and states that easily grant exemptions are associated with increased pertussis incidence. States should examine their exemption policies to ensure control of pertussis and other vaccine-preventable diseases.