During that same period, however, the number of medical exemptions issued for childhood vaccinations has more than tripled.
Now, results of a new study published in Pediatrics show that parents -- and, in some cases, health care professionals -- are using weaknesses in the law to their advantage, a subject that is sparking concern among health officials throughout California.
In the aftermath of a measles outbreak at Disneyland in late December 2014, Gov. Jerry Brown signed S.B. 277 into law on June 30, 2015. Among other things, the legislation required children enrolled in a public or private school or daycare center to be vaccinated against 10 specific childhood diseases, including measles, mumps and pertussis, beginning July 1, 2016.
The new law also eliminated provisions for personal belief exemptions, making California one of only three states that do not allow nonmedical vaccine exemptions. Mississippi and West Virginia have similar laws on the books.
But whereas Mississippi and West Virginia call for all medical exemptions to be reviewed by state health officials, no such review process exists in California. The legislation requires only that physicians be licensed by the Medical Board of California or the Osteopathic Medical Board of California to issue such exemptions, which parents or guardians of children submit directly to schools.
Specifically, the law allows children to be exempt from immunizations if the child's parent or guardian provides a statement from a licensed physician to "the governing authority" of a school or school district establishing that "… the physical condition of the child is such, or medical circumstances relating to the child are such, that immunization is not considered safe."
Finally, although the law requires governing authorities to report on the immunization status of children and work with county health officials to administer immunization programs, it does not give them the authority to challenge medical exemptions.
To better understand the effect of California's law on vaccine exemptions, the Pediatrics study authors interviewed 40 health officers and immunization staff -- all of them members of the Health Officers Association of California, an organization that represents health officers in California's local health jurisdictions. Interviews were conducted in August and September 2017, and included health officers, immunization coordinators and directors, communicable disease directors, and public health nurses.
The interviews revealed frustration and concern among health officials regarding the rise in medical exemptions, as well as about how they now are being issued. They also took issue with not having the authority to review exemption decisions.
In one instance, an immunization coordinator in an urban jurisdiction related how a physician switched from issuing permanent medical exemptions to temporary exemptions while charging high fees for these services.
"I'm getting a very high volume of medical exemptions from one provider, and from what I understand, for all intents and purposes, she's selling these medical exemptions," said the coordinator. "She used to just give permanent medical exemptions, and now she's giving temporary for three months. So, now families have to go back every three months and pay $300 to get their temporary medical exemption updated."
In another instance, a physician submitted a statement requesting a "temporary" medical exemption through July 2030. "That's one hell of a temporary exemption," said the health officer who reviewed the statement.
In a third instance, a health officer reported having more authority to approve or deny vaccine exemptions for dogs than for children.
"I don't get to approve or disapprove the medical exemptions. The law didn't give the health officer any role, and I'll tell you how ridiculous this is. In comparison with the fact that I have to review dog rabies vaccine exemption requests and I get to see medical records of dogs and I have the authority to disapprove requests for exemptions for rabies vaccines … and for people, we don't have that authority," the health officer confided.
Other concerns included the following:
The study authors also reviewed information from the California Department of Public Health and noted that the proportion of kindergarten students who received all of the required vaccines rose from 92.8 percent in the 2015-2016 school year (the academic year before S.B. 277 took effect) to 95.1 percent in the 2017-2018 school year.
But that increase has been offset to a degree by the increase in medical exemptions, with rates increasing from 0.2 percent in 2015-2016 to 0.7 percent in 2017-2018.
And although the number of medical exemptions issued in the past couple of school years has not yet reached the level of personal belief exemptions that were claimed before the law took effect, evidence indicates a trend in that direction.
"If medical exemption rates continue to rise, portions of California will remain susceptible to vaccine-preventable outbreaks," the authors cautioned.
The study authors also pointed to problematic language in S.B. 277 itself, which allows physicians to base a medical exemption decision on "family medical history." Because the law does not clearly define what aspects of family medical history should be considered, physicians have issued medical exemptions on the grounds of a family history of allergies and/or autoimmune disorders, even though the Advisory Committee on Immunization Practices does not consider these medical contraindications to immunization.
"Some physicians may continue to write medical exemptions for children without scientifically justified medical contraindications to vaccines," the authors wrote. "Without additional legal changes to S.B. 277, including a standardized review of medical exemptions, this could potentially undermine and limit the long-term impact" of the legislation.
In a related commentary Richard Pan, M.D., M.P.H., a California state senator from Sacramento who helped write S.B. 277, and Dorit Rubinstein Reiss, L.L.B., Ph.D., of the University of California Hastings College of the Law in San Francisco, stated that "Policymakers should recognize that granting medical exemptions to legally required vaccines is not the practice of medicine but a delegation of state authority to licensed physicians to protect public health and individuals." Physicians who grant medical exemptions, therefore, "are fulfilling an administrative role" delegated to them by the state, which has a constitutional duty to protect public health and safety.
"This delegation makes sense," the commentary authors continued, "because physicians already evaluate patients for existing health conditions and can identify which of their patients warrant medical exemptions." They further note that according to standards of care established by medical professional associations, granting unwarranted medical exemptions constitutes unprofessional behavior that may be subject to potential liability and discipline by a state licensing board.
Difficulty arises, however, when families who seek unwarranted medical exemptions aren't willing to release patient records needed to investigate the physicians who grant them. Add to that the fact that professional standard-setting organizations have historically been reluctant to censure clinicians "who promote vaccine misinformation and grant unwarranted medical exemptions."
For these reasons, public health officers should be allowed to review medical exemptions, invalidate exemptions that are not justified, and revoke the authority to grant medical exemptions from physicians who abuse it, the commentary's authors concluded.
The California AFP supported S.B. 277 and praised the bill's passage. In a statement to AAFP News, the chapter said it was pleased with the improved vaccination rates but concerned about some of the reports noted in the health officer interviews.
"We are very concerned with any physician offering exemptions that are not based on the medical condition of the patient, as specified in the law," said the statement. "CAFP finds it unconscionable that a physician would base an exemption solely on payment, putting their communities and immunocompromised patients at risk."
California AFP President Lisa Ward, M.D., of Windsor, noted that although medical exemptions have increased, the overall effect of S.B. 277 has been positive.
"It is important to keep in mind that even with an increase in medical exemptions, the improvements in immunization rates show the positive result of this legislation," she said.
"Vaccines are one of the safest and most powerful tools for improving public health," Ward added. "Along with other primary and preventive care services, we need to do our best to ensure all patients have access to this important health measure."
To that end, the California AFP is considering options to fix some of S.B. 277's loopholes that would keep immunization rates high without creating additional issues.
"We are currently exploring the ways we can best assure that communities have herd immunity, as well as methods to prevent exemptions not rooted in legitimate medical concerns," said the California AFP statement. "A review process may be one strategy; however, we want to ensure that any such process would not have unintended consequences and would respect the art and science of family medicine."
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