California’s Vaccination Rate Slips as Medical Exemptions Rise

In the last few years California has gained ground in its fight to protect children from infectious diseases. But new data released this week shows that the state’s vaccination rate declined for the second year in a row.

Last fall 94.8 percent of California kindergartners had received all their shots, down from 95.6 in 2016-2017. That drop may look small, but California has about as many kindergartners as Wyoming has people. The most recent figures show that California now falls below the Centers for Disease Control and Prevention’s recommended vaccination rate of 95 percent, considered necessary to protect a community from disease outbreaks through herd immunity. Those numbers also obscure big differences in vaccination rates from one zip code to another, spanning from as low as 19 percent in one community in northern Los Angeles County to as high as 99 percent in Watsonville, California.

Four years ago, following a measles outbreak in Southern California that began at Disneyland, California passed SB277, a law that eliminated parents’ ability to opt out of mandated vaccinations for their kids based on personal beliefs. At first, the law seemed to be working. When it was passed, 2.4 percent of kindergartners in California weren’t vaccinated because of a personal belief exemption; today, that figure is zero.

But children can also skip vaccinations if they receive a permanent or temporary medical exemption from a doctor; these are typically given to children who have health conditions, like immune system disorders, that contra-indicate vaccination. Five years ago, just 0.2 percent of California students received a permanent medical exemption, while 2.5 percent claimed a personal belief exemption, or PBE. Since the PBE’s elimination, permanent medical exemption (PME) rates have begun to climb, from 0.7 percent to 0.9 percent for the past year.

California Department of Public Health data suggests that communities in which PBEs were popular in the past may now be obtaining PMEs. As Barbara Feder Ostrov reported in Kaiser Health News earlier this spring, many schools that previously claimed the highest PBE rates now have high PME rates.

New data released this week backs up this analysis. The California schools with the highest exemption rates today—we’re talking rates of 40, 50, even 64 percent of a group of a few dozen kindergartners—had PME rates of zero five years ago. So five years ago, kindergarten classes at these schools had no children whose health was compromised to the degree that they could not medically handle immunizations. At the time, those same schools claimed very high PBE rates—ranging from 35 percent to 87 percent. About half of the schools with the highest PME rates are Waldorf schools. (Waldorf schools follow an educational model developed by Rudolf Steiner and Emil Molt that emphasizes bringing out each child’s individual potential in a way that serves humanity.)

Take Yuba River Charter, a Waldorf-affiliated school in Grass Valley, California. (Grass Valley is northeast of Sacramento, in a county where 10.6 percent of kids have a PME and only 80.3 percent are fully vaccinated.) In 2013, more than two-thirds of Yuba River Charter’s kindergartners claimed personal belief exemptions. Today, that figure is zero. But just 36 percent of students at the school are vaccinated, with the remainder claiming a permanent medical exemption. (Administrators did not respond to a request for comment.)

Private schools have lower immunization rates than public ones: This year 95 percent of children entering public kindergarten had all their shots and 0.7 percent had medical exemptions, while 92.9 percent of private school kindergartners were fully vaccinated and 2.4 percent claimed permanent medical exemptions.

The permanent medical exemption rates don’t tell the whole story, says Leah Russin, executive director of Vaccinate California, a parent group that advocates for vaccination. (WIRED contributor Renee DiResta is a cofounder of Vaccinate California.) Russin explained that the state also reports on the percent of students who enter schools conditionally—meaning, they aren’t fully vaccinated but plan to be in the future. Those numbers include students who have received a Temporary Medical Exemption from their physician. “Kids might not receive a permanent exemption because a temporary exemption is all that’s being offered by the doctor they’re working with,” Russin says. “There’s one doctor who will give a 90-day temporary exemption if you call, and then you have to follow up and get one for a longer term.” (Earlier this year the Voice of San Diego identified a single physician behind one-third of medical exemptions written for students in the San Diego Unified School District.)

Through a public records request, Russin received data from the California Department of Public Health that breaks out the share of students who received temporary medical exemptions. In the 2018-2019 school year, dozens of schools had TME rates of 10 percent or higher, while their PME rates are low. At Highland Hall Waldorf school, in the Northridge area of Los Angeles, 34 percent of students have a temporary medical exemption, while only 4 percent have a permanent exemption. Thirty miles east in Altadena, it’s a similar story at another Waldorf school. “All members of our association are independent and make decisions in accordance with our membership and accreditation criteria,” says Beverly Amico, executive director for advancement at the Association for Waldorf Schools of North America. “These criteria include the expectation that all schools be compliant with national, state, provincial and local laws.”

The augmented California data, which Russin shared with WIRED, shows a statewide TME rate of 0.2 percent—that’s on top of the 0.9 percent of students receiving permanent medical exemptions, bringing the state’s total medical exemption rate to 1.1 percent.

Click here for a larger view of this map.

The rise in medical exemptions has not gone unnoticed. Last month the California Senate passed SB276, a bill that would set statewide standards for medical exemptions. Authored by California senator Richard Pan, a pediatrician from Sacramento, the bill aims to reduce the rising rate of medical exemptions in the state and is supported by the California branch of the American Academy of Pediatrics and the California Medical Association. The bill now moves to California’s state assembly for consideration; there are questions about whether Governor Gavin Newsom will sign the bill should it reach his desk.

The rise in medical exemption rates isn’t entirely a surprise, says Catherine Flores Martin, executive director at the California Immunization Coalition, a Sacramento-based nonprofit that supports immunization. “We knew that after SB 277 passed, the medical exemptions would go up, because we thought that some PBEs might really be medical exemptions that weren’t formalized by the parent.” But the rates continue to rise. “Some physicians are writing these exemptions for things that do not fall under established guidelines, and that’s not safe for public health.” Senator Pan’s bill doesn’t mandate immunizations, Flores Martin says; parents who choose not to can, for example, opt to home-school their kids. “Nobody is forced to vaccinate their children.”

No one in California is forced to vaccinate children, but in the wake of a measles outbreak in Brooklyn, the New York City health department recently mandated that people who work or live in four zip codes get the measles, mumps, and rubella vaccine or face a $1,000 fine. (Medical exemptions, however, are permitted.)

Last month a paper in The Lancet Infectious Diseases identified the 25 US counties most at risk of a measles outbreak. Three California counties, Los Angeles, San Mateo, and San Diego, made the researchers’ top 25 list. According to the California Department of Public Health data, while 98 percent of San Mateo kindergartners and 96.4 percent of LA kids received the MMR, only 94.3 percent of San Diego kids were fully protected against measles, below the herd immunity level of 95 percent. This year 51 people have contracted measles in the state, with 10 cases in Los Angeles to date.


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