Photograph by Damian Dovarganes, AP

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A health care professional prepares a single dose of the measles, mumps, and rubella vaccine, or MMR, at a California doctor's office. The current measles outbreak has primarily affected unvaccinated people.

Photograph by Damian Dovarganes, AP

Young Adults Most Worried About Vaccines, Poll Finds

Some 41 percent of people younger than 30 favor allowing parents to not vaccinate their kids.

Younger adults are more likely than older Americans to harbor doubts about getting their vaccinations, new Pew Research Center survey data reveals. Meanwhile, a U.S. measles outbreak this winter has revved up worries that not enough young parents are fully vaccinating today's children.

Millennials generally credit science more strongly than older folks do, but the results show that on vaccines they are more distrustful. Some 41 percent of adults under age 30 favor allowing parents to "decide NOT to vaccinate their children." The older people were, the less inclined they were to regard vaccination as a parental choice. Among adults 65 and older, only 20 percent of those responding favored allowing parents to decide.

The generation gap intrigues public opinion experts, and may reflect faded memories among the young of ailments now largely staved off by vaccination. (See "The Anti-Vaccine Generation: How Movement Against Shots Got Its Start.")

"What's interesting are the age gaps," says public communications expert Dominique Brossard, of the University of Wisconsin in Madison, by email. "It might be that relative to other age groups, higher proportions of millennials have no problem accepting science in some areas (especially if it fits their life choices) but rejecting it in others, such as vaccinations."

Pew telephone surveys conducted last weekend found that 90 percent of U.S. adults age 50 or older see measles vaccines as "safe for children." But the fraction agreeing with that statement drops to 77 percent of adults under 30, prime childbearing years.

Middle-aged adults lean closer to the young, with 81 percent viewing the measles vaccine as safe.

Safety in Numbers

As of last week, 121 U.S. cases had been reported in the current measles outbreak, according to the U.S. Centers for Disease Control and Prevention in Atlanta. Most of the stricken were unvaccinated.

In January, Pew had reported a survey showing fissures between the U.S. public and experts on contentious science, including climate change and vaccinations. More results of that polling released on Thursday break down science doubts according to age, political affiliation, and more.

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This deeper dive into the doubt data shows that distrust of evolution and climate science is more common among older adults, just as in past surveys. But skepticism about requiring vaccinations in general—separate from the question of measles vaccine safety polled over the weekend—also is more common among younger people. (For more, see "Why Do So Many Reasonable People Doubt Science?" in National Geographic magazine.)

Attitude Adjustment

Pew's January survey of 2,002 U.S. adults found wide variations in who doubts what in science.

— U.S. Hispanics in the poll reported more conviction about global warming than others, with 70 percent convinced that "Earth is getting warmer mostly because of human activity," against 44 percent of U.S. whites.

— Gender splits views on genetically modified foods, with 47 percent of men seeing them as "generally safe" versus only 28 percent of women.

— Skepticism about both human evolution and global warming rise with age, doubted by 37 percent and 35 percent, respectively, of adults 65 or older.

Mistrust of human evolution was tied to education; the concept was doubted by 39 percent of respondents with just a high school diploma. That was nearly twice the rate seen among college graduates. Education had no bearing on climate attitudes.

Generation Gap

Politics does play an "emerging" role in vaccinations now, suggests Pew's Lee Rainie in an analysis of the January data finding a split between Republicans, with 34 percent saying "parents should decide" whether to vaccinate kids, and Democrats, who polled at 22 percent.

That's a bigger split than surveys saw in 2009, when both groups fell closer to the middle of the current spread. Attitudes toward global warming are even more divided between the parties, a split that has been evident in polls for at least two decades.

But the new February poll that looked only at the measles, mumps, and rubella vaccines found unity within the survey's margin of error among Republicans and Democrats, with 89 percent and 87 percent of respondents, respectively, finding them safe.

Yale polling expert Dan Kahan is dubious about any political link to vaccine views, pointing to very high inoculation rates among U.S. children overall, higher than 90 percent over the past decade. (The CDC says at least 92 percent of children need a measles vaccination for a community to be protected by herd immunity.)

A 2014 survey released by his research group found that 75 percent of U.S. adults favor vaccinations. "Everyone loves vaccines," according to those results, Kahan says, regardless of political party.

"Often public attitudes are more nuanced than the polling questions might indicate," says Pew's Cary Funk. "But the first step is just to start asking questions."

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