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Exemptions From Vaccines Up Slightly In California Since 1980s


The reasons parents in California are choosing not to immunize their kids today is partly due to what they find on the Internet, including a study that incorrectly linked vaccines to autism.

Decades ago, parents who chose not to immunize their kids for philosophical or religious reasons were a tiny fraction of the population, according to an inewsource analysis of California data.

Their numbers are still small, but they grew from about one-half of a percent in the 1980s and ‘90s, to 2.5 percent statewide in this most recent school year.

“Parents did not question the vaccines at that time. I think there was a lot more confidence and trust in the physicians,” said Catherine Flores-Martin, director of the California Immunization Coalition, a vaccine advocacy group.

Photo caption:

Photo credit: Piktochart / Leo Castaneda

The chart above details the personal belief exemption rate in California. It shows that personal exemptions have increased from about one-half percent in the 1980s and '90s, to 2.5 percent in the 2014-15 school year.

Blame the Internet and a now discredited study linking autism to vaccines for the mistrust and misinformation about vaccine safety, Flores-Martin said.

“Parents were able to do research on things that concerned them and get more acquainted with medical information,” she said, referring to the early days of the Internet. “And they found studies that may have supported their beliefs, however incorrect that they are.”

To Flores-Martin’s point: Google “vaccine” and “autism” and more than 10 million results appear, including many sites that continue to incorrectly link vaccines to autism.

The debunked study by British researcher Andrew Wakefield in 1998 helped get the anti-vaccine movement started. Wakefield’s study looked at 12 kids with autism, and claimed there was a link between the MMR (measles, mumps, and rubella ) vaccine, autism, and bowel disease. The paper was officially retracted in 2010.

Before Wakefield’s study, in the 1994-95 school year, the personal belief exemption rate was 0.5 percent in California. In the 2000-2001 school year, two years following the publication of Wakefield’s paper, personal belief exemptions climbed to more than 7 percent.

By 2004, they fell back down to just over 1 percent and have slowly been crawling upward, with the exception of this most recent school year when they fell slightly.

Photo caption:

Photo credit: Piktochart / Leo Castaneda

The chart above shows the up-to-date vaccination rate in California by year. In the 1984-85 school year, just under 85 percent of kindergarteners were up to date with their vaccines, compared to 90 percent in the 2014-15 school year.

Overall vaccination rates in California have increased dramatically in the past three decades. In the 1984-85 school year, just under 85 percent of kindergartners were up to date with their vaccines, compared to more than 90 percent this year. Flores-Martin said lack of access was the biggest reason children didn’t get immunized in the 1980s.

That changed when Congress created the Vaccines for Children Program in 1993. It followed one of the worst measles outbreaks in the U.S. between 1988 and 1990. There were more than 16,000 cases and 75 deaths, with low-income Hispanic children and young adults who weren’t immunized among the most impacted.

A recent measles outbreak that can be traced to Disneyland has raised awareness about parents who choose not to vaccinate their children. It has sickened more than 150 people in 17 states, according to the most recent Centers for Disease Control and Prevention statistics.


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