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How vaccines stop the spread of viruses
01:26 - Source: CNN
CNN  — 

More than a third of US parents say that vaccinating children against measles, mumps and rubella should be an individual choice and not a requirement to attend public school, even if that may create health risks, according to survey data published Friday by the Kaiser Family Foundation.

That’s a notable increase from pre-pandemic times. A similar poll from the Pew Research Center found that 23% of parents opposed vaccine requirements in schools in 2019, but that’s now jumped to 35% in the KFF survey.

All 50 states and the District of Columbia require children attending public school to be vaccinated against certain diseases, including measles and rubella. Exemptions are allowed in only some circumstances.

In central Ohio, a measles outbreak that started last month continues to grow, spreading entirely among children who were not fully vaccinated.

As of Thursday, 77 children had a confirmed case of measles, and more than a third of them were hospitalized, according to data from Columbus Public Health. The vast majority of the children were completely unvaccinated against measles, and four had received half of the recommended two-dose series.

“What’s really driving this is, unfortunately, a lack of vaccination, which is just heartbreaking,” Dr. Nora Colburn, an adult infectious diseases physician at The Ohio State University Wexner Medical Center in Columbus, said this month.

About 90% of unvaccinated people who are exposed to measles will become infected, according to Columbus Public Health, and about 1 in 5 people in the US who get measles will be hospitalized.

During the early days of the Covid-19 pandemic, while most people stayed home and some health-care facilities were closed, many children missed their routine immunizations, including the MMR vaccine – and they still may not have gotten all their recommended shots. That’s true around the world as well as in the US.

“Measles is such a contagious disease that when you see those dips [in vaccine coverage], we really worry about the potential for large outbreaks,” said Dr. Sean O’Leary, chair of the American Academy of Pediatrics’ Committee on Infectious Diseases and professor of pediatric infectious disease at the University of Colorado School of Medicine and Children’s Hospital Colorado. “You need to really maintain a high vaccination coverage to keep measles from spreading.”

While the KFF survey shows that skepticism around the Covid-19 vaccines has grown, belief in the value of childhood vaccines has changed little: About 85% of adults in the new survey say that the benefits of the measles, mumps and rubella vaccines outweigh their risk, down only 3 percentage points from 2019.

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But support for requirements of these vaccines has plummeted, especially among Republicans. The share of Republicans who say that parents should be able to opt out of these childhood vaccines has doubled since the start of the Covid-19 pandemic, up from 20% in 2019 to 44% now. Among Democrats, however, support for vaccine requirements in public schools has stayed consistently above 85%.

The latest survey from KFF’s ongoing COVID-19 Vaccine Monitor project was conducted from November 29 to December 8.

CNN Health’s Jacqueline Howard contributed to this report.

Correction: A line in a previous version of this story incorrectly described the vaccination status of children diagnosed with measles in Ohio.