This article is more than 1 year old

This article is more than 1 year old

A measles outbreak which has spread from south-west Washington to other parts of the Pacific north-west has highlighted low vaccination rates in the region, and the danger the disease presents to unvaccinated children.

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The development has sparked concerns that parents deliberately choosing not to vaccinate their children – out of scientifically unfounded concerns that vaccinations can harm them – are leading to epidemics that could easily be avoided.

Washington governor Jay Inslee recently declared a state of emergency in response to a growing number of measles cases in the city of Vancouver, which lies within Clark county in the south of the state.

By 29 January, Clark county public health (CCPH) had identified 36 confirmed cases of measles and 12 suspected cases. Twenty-five cases involved children under 10, 32 of those affected had not been immunized, and the remaining four had an unconfirmed vaccination status.

CCPH also listed a range of exposure sites including schools, health centers and restaurants. Prominent among the sites were a number of Vancouver-area evangelical churches and Christian academies.

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Across the Columbia River in Portland, Oregon, one confirmed case had been identified by 29 January. Exposure sites there included a church; the Moda Center, where the Portland Trailblazers play NBA games; and the Oregon Museum of Science and Industry, an attraction which is popular with the city’s children. Another case has been confirmed in King county, which contains Seattle.

Clark county vaccination rates among children are low, and far below what they were in previous decades. Between the 2004-2005 school year and 2017-2018, vaccination rates among Clark county kindergartners fell from 91.4% to 76.5%.

Facebook Twitter Pinterest A sign posted at a clinic in Vancouver, Washington warns patients and visitors of the outbreak. Photograph: Gillian Flaccus/AP

State laws in Oregon and Washington require students who attend schools, or engage with other institutions beyond their home to be vaccinated against a range of diseases. But, unlike in other states, where parents can ask for exemptions on medical grounds, in Oregon and Washington parents can ask for exemptions on religious or philosophical grounds relatively easily.

They do so in significant numbers. According to the CDC, in Oregon 7.5% of kindergartners had non-medical exemptions from vaccinations in 2018. In Washington, it was 3.9%.

Dawn Nolt, an assistant professor of pediatric diseases at Doernbecher children’s hospital in Portland, said that while measles is only rarely deadly, “it has high consequences” for the short-term health of its victims. She said measles is also highly contagious, and will spread to 90% of unvaccinated people who are exposed to a carrier of the disease.

She has seen an increase in what practitioners call “vaccine hesitancy”, and she added: “I do wonder whether the advent of social media has empowered that anti-vaccine movement.”

Nolt said that vaccine hesitant parents lie on a spectrum. Some refuse vaccines altogether. Some pick and choose between vaccines based on their beliefs about which ones are harmful. Others accept vaccines, but only on a timeline of their choosing, according to fears about the “overloading” of infant immune systems with multiple vaccination.

She also said that refusal comes from a number of different motivations. Some parents have safety concerns. Some are resistant to authority or government. And some “believe conspiracy theories about vaccination and its outcomes”.

There is now a global concern over “vaccine hesitancy”, which the World Health Organization has named as one of its top threats to global health in 2019.

The measles, mumps and rubella vaccine (MMR) has been a particular focus of “anti-vaxxer” scare campaigns. In 1998, since discredited physician Andrew Wakefield published fraudulent research in the Lancet which suggested that the vaccine had a role in causing autism.

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A range of physicians and medical authorities have directly attributed a subsequent decline in vaccinations in many parts of the western world to the publication of Wakefield’s material, which has led to a belief that there is a connection between vaccines and autism.

Wakefield is revered by many in the anti-vaccination movement, which appears to be growing. Now living in the US, he has spoken to gatherings of alternative health practitioners, and in 2016 directed an anti-vaccination propaganda film.

Nolt, meanwhile, said the approach to the problem of vaccine hesitancy is changing.

“When providers have talked to vaccine-hesitant parents in the past we have tried to be logical and to bombard them with facts. That doesn’t always work”, Not said.

“Now we don’t talk about the vaccine and how safe it is,” Nolt said. “Now we talk about the disease.”