More Washington kids get the measles vaccine, thanks to a rule change

More school kids in Washington state have been getting vaccinated against measles. That’s because, after measles outbreaks in 2019 — including a major one in the Portland/Vancouver area — legislators tightened who could opt out of the shots.

Parents can still opt their kids out of the measles vaccine for medical or religious reasons, but not because of their personal beliefs. That policy change led to roughly one more kindergartener out of every 20 getting the measles shots, according to a new study.

Clark County, where the major outbreak took place, saw an even more dramatic increase.

The study’s authors wanted to sort out why vaccination rates in Washington increased: Was it because the measles outbreaks made parents more nervous about the disease? Or was it because of the policy change?

To figure that out, the researchers looked across the border at vaccination rates in Oregon, which also suffered from the 2019 measles outbreaks but did not change its vaccination rules.

“There was no change [in vaccination rates] over the same time period in Oregon,” said Julia Bennett, a PhD candidate in epidemiology at the University of Washington, and one of the study’s authors. “That strengthened the evidence that the increase in measles vaccine coverage in Washington was due to this new legislation.”

Parents in Washington can still opt their kids out of other school-required vaccines, like for polio, by claiming the shots are against their personal beliefs.

Bennett said when California tried to remove all non-medical exemptions for all vaccines, there was a backlash, and parents responded by getting medical exemptions for their kids.

She said Washington’s more targeted approach seems to have been more successful at increasing vaccination rates.

“In response to outbreaks of vaccine-preventable disease, this type of [focused] legislation is an opportunity to increase coverage for that vaccine to prevent future outbreaks,” Bennett said.