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Anti-immunization holdouts are putting all Arizonans at risk

Back in 1796, a British doctor named Edward Jenner performed the first smallpox vaccination. By the 1830s, his breakthrough discovery had struck a decisive blow against the vicious disease.

Around that same time, anti-vaccination zealots began railing against Jenner's marvelous discovery. The cure, they argued, was more perilous than the disease itself.

This would not be the last time that good science battled dark superstition. Fast-forward to 2012, when a growing movement, stoked by Internet hysteria and celebrity prattle, is resisting the vaccination of children for potentially deadly illnesses such as measles, whooping cough and rubella.

As social trends go, health officials say, this one is particularly animated by foolishness, and puts all children at risk.

"Getting your kids vaccinated is not necessarily just about protecting your individual child," says Will Humble, director of the Arizona Department of Health Services. "It's really a social contract you have with your community."

Depending upon the whereabouts of your community, that social contract may be fraying. According to a joint study by ADHS and UA College of Public Health researchers, pockets of parents scattered around Arizona are refusing to have their children vaccinated. As Arizona is one of only 20 states that allow "personal belief" exemptions, kids can enroll in school without the shots if the parents oppose vaccinations for any far-fetched reason.

Today, a growing number of parents are claiming those exemptions. That's disturbing news; according to the ADHS, numerous outbreaks of chickenpox, whooping cough and measles have been directly traced to unvaccinated kids in states offering such waivers.

To UA professors Kacey Ernst and Beth Jacobs—parents themselves—peeling back the layers of this trend became a professional task with personal overtones. The results of their study will be released early this spring, but already, a few key findings stand out.

Most striking is the fact that pockets of nonimmunized children are not necessarily found among the poor, who tend to have mundane reasons for not getting their kids vaccinated, such as money, time or transportation. Instead, "when you look at who's taking the exemptions, they tend to be people who are upper-middle class," Ernst says, "people who are fairly well-educated. And a lot of it seems to be linked to this fear of vaccines and autism."

The public face of that fear is actress Jenny McCarthy, the mother of an autistic son who has run a high-profile campaign promoting a link between the measles-mumps-rubella, or MMR, vaccine and autism. Her controversial stance has even prompted the website Jenny McCarthy Body Count, which purports to track the number of illnesses and deaths in the United States since 2007 that could have been prevented by immunizations.

According to the site, the number of illnesses stands at just more than 87,000; the number of deaths has reached 866.

McCarthy and her backers leave medical researchers shaking their heads. "Even though there's no scientific link (between vaccines and autism), it's out there, and communities that have really strong anti-vaccination campaigns are all over the Internet," Ernst says. "And as a parent, when you're trying to choose whether or not you're going to vaccinate your child, one of the main sources you're going to use for information is the Internet."

This attitude is actually reinforced by the very success of vaccines, Ernst says. "If you have a child, and you're looking at all these pseudo-science websites, and you don't see people in your community getting measles or getting sick from something, you're probably going to lean toward not vaccinating."

But if enough people take that position, communities may eventually reach a tipping point. This has to do with what epidemiologists call "herd immunity," meaning that an adequate percentage of a population must be immune to an infectious disease—either through a prior illness or vaccination—for the disease to have little chance of spreading. Fall below that threshold, and you're bound to see an outbreak.

Between 2001 and 2008, there were more than 500 confirmed cases of measles in the United States, with the three largest flare-ups occurring among families who claimed personal-belief exemptions. Children not immunized for chickenpox were nine times more likely to get it. And those who weren't vaccinated against whooping cough were nine times more likely to get that preventable and dangerous disease.

Take those numbers, and extrapolate them across a growing segment of society that refuses to vaccinate its children, and you have the recipe for a medical catastrophe.

One bright note: Though stats were not immediately available for Pima County, "Tucson is actually doing pretty well," Ernst says. "We do not have as many of those personal-belief exemptions being taken in our community." That's a testament to our local public health folks, she says, and their emphasis on the importance of immunizations.

Meanwhile, the number of immunization holdouts in other parts of Arizona is still rising, Ernst says. "Those are the areas that we're really concerned with: trying to understand the dynamics of why, and what we can do with education to help parents understand why immunization is important."

Yavapai County appears to be ground zero for the anti-immunization crowd. Among kindergartners there, 8.5 percent were not vaccinated, and the exemption rate among sixth-grade students is a whopping 9.8 percent. Boosting those numbers was the upscale, new-age mecca of Sedona, where exemption rates in at least one ZIP code reached nearly 50 percent.

Statewide, personal-belief exemptions have risen from approximately 1 percent a decade ago to 3 percent today, Ernst says. "If we keep on that trend, in another 10 years, you're going to be looking at overall state rates that are verging on impacting herd-immunity levels." According to state health officials, the public-health threat is heightened whenever the number of non-immunized students reaches 10 percent.

Nor is Pima County completely immune to anti-immunization rhetoric, considering that we are trending in the wrong direction: According to the Pima County Health Department, the percentage of children not vaccinated due to personal-belief exemptions grew from 2.9 percent in 2009 to 3.4 percent a year later.

In light of this progression, eerie parallels with the past are unavoidable.

"Last month, on a weekend, I went into some medical journals from the 1800s," says the UA's Beth Jacobs. "I was reading about the anti-vaccination movement when the smallpox vaccine came out. And what so utterly amazed me is how the rhetoric used then is identical to the rhetoric used today. In 100 years, nothing has changed."