Senate Bill 277: Ending Non-Medical Vaccine Exemptions in California Schools

Nikhil Nunna

In 2015, California passed Senate Bill 277 (SB 277), eliminating non-medical exemptions for vaccinations in public and private schools. Driven by a measles outbreak at Disneyland, the bill marked one of the nation’s strongest stances on vaccinations for children, reinforcing public health over personal preferences.

Before SB 277 was passed, parents in California schools had the choice to cite personal or religious reasons to opt their children out of required immunizations for school entry. However, after a growing number of measles cases were linked to non-medical vaccine exemptions, the law was enacted to address this loophole, mandating immunizations for attendance in public and private primary and secondary schools and daycare centers.

Key Provisions of SB 277
Parents or guardians can no longer claim personal, philosophical, or religious reasons to exempt their children from the required immunizations to attend public or private schools. Applying uniformly to all California schools, the only path to exemption allowed under the law is through a medical exemption issued by a licensed physician. A medical exemption requires that physicians detail the medical reasons why immunization would be unsafe for the child. The only exceptions to SB 277 are for children attending home-based private schools or independent study programs without classroom-based instruction.

Why It Matters
SB 277, enacted in 2015 and effective in 2016, underscores California’s commitment to protecting public health and vulnerable communities, especially children who cannot be vaccinated for medical reasons, from preventable diseases. It reflects a core concept from public health science: herd immunity only works with high vaccination rates.

Moreover, the law sends a strong message about prioritizing collective well-being over individual beliefs. By reducing disease resurgence, California schools become safer, parents gain confidence, and public health burdens decrease.

Effects
Following the law’s implementation, vaccination rates among kindergarteners rose. According to an article from Vaccine, the rate increased from 90.4% before the law’s implementation to 95.6% by the 2016-2017 school year.

While the law was successful in increasing immunization rates, it sparked fierce opposition from parental-rights and anti-vaccination groups, leading to protests, recall campaigns targeting SB 277’s author, Senator Richard Pan, and even death threats.

Although not a significant consequence of the law, one study with a limited sample size reported that many homeschooling parents cited immunization mandates (such as SB 277) as a reason to homeschool and considered moving out of California due to such mandates.

SB 277 remains a vital pillar of California’s public health policy today. While controversial, it has had a clear impact, boosting vaccination rates and increasing school safety. As public health evolves, the law may serve as a benchmark for future vaccination policy.

Image courtesy of The Los Angeles Times.