13,000 N.J. school children are unvaccinated. Use our tool to find out the risk in your district.

Roughly 13,000 children in New Jersey are missing vaccines that could protect them from childhood illnesses, according to data from the New Jersey Department of Health.

Child vaccination has come under increasing scrutiny in recent weeks as outbreaks of the measles, a disease long-absent from society — have become more frequent. The most recent outbreak in New Jersey has climbed to 13 cases, according to health officials.

But far more schools are at risk of becoming the next place where children get sick from vaccine-preventable diseases.

At least 490 New Jersey schools have immunization rates below the required level to protect unvaccinated children attending them. Within those, a few dozen schools are pockets of very low compliance rates, making them potential hubs of infection if the measles outbreaks continue.

The reason, advocates say, is the small but increasing frequency of anti-vaccine beliefs within some local communities. “Like measles itself, the movement just takes on a life of its own,” said Michael Weinstein, director of the New Jersey Immunization Network, which educates the public about vaccine safety.

Researchers worry when the vaccination rate drops below what’s called the “herd immunity level,” the point where vaccinated kids are so common, and unvaccinated children so few, that it’s hard for a disease to spread among the unvaccinated children.

“If most people are pro-vaccine and one person is anti-vaccine, that child’s exposure is quite low,” said Rupali Limaye, associate director of the Institute of Vaccine Safety at Johns Hopkins University.

Statewide, 95 percent of children meet the full requirements for immunization for their grade, above the limit most diseases require for herd immunity. On a county level, Warren county is the lowest, with 92.7 percent meeting vaccine requirements.

Parents can seek different exemptions to avoid meeting those requirements. The number of parents seeking medical exemptions — for conditions that make the child’s immune system too poor to handle vaccines — was about the same in 2017-2018 as in previous years. The number of religious exemptions, on the other hand, has spiked from 1.7 percent to 2.4 percent statewide, and reaches even higher in certain schools.

“Those instances where families are using the philosophical approach but get the religious exemption are hard to nail down,” Weinstein said.

Dr. Puthenmadam Radhakrishnan, a pediatrician who works in Ewing and Trenton, said access to vaccines is another problem for low-income families. The state provides Medicaid for children, but not all providers accept it, he said.

He’s seen the results of poor vaccination firsthand when flu season hits. “It starts off slowly, then suddenly 20 to 30 percent of the school is out,” said Radhakrishnan, who also works with NJIN through its partner, the American Academy of Pediatrics.

Last year, the state legislature considered eliminating the religious exemption but faced backlash from religious and anti-vaccine groups. Parents contended that it removed their freedom to choose for their children.

But Limaye pointed out many anti-vaccine parents are basing their decisions on misinformation about the dangers of vaccines. They overestimate the number of chemicals in the ingredients, overestimate how often adverse reactions happen, and underestimate how early their child needs to start getting vaccines to be protected by the time they get to school.

“We need to focus on the people who have concerns and not be dismissive of them,” she said. “We need to use accessible ways to talk about the science.”

Dr. Radhakrishnan urged parents who were struggling to get their children vaccinated to look into low-cost or free programs, like Vaccines for Children. He said outbreaks of vaccine-preventable diseases are “the worst thing that we see. This is what pediatricians are trying to provide.”

The state provided school-level vaccination data in response to a records request. However, there are a few things parents should know before they take a look. These numbers are self-reported by schools and not verified by the state. We eliminated schools where the numbers didn’t add up, but we can’t guarantee these schools are accurate, either.

Erin Petenko may be reached at epetenko@njadvancemedia.com. Follow her on Twitter @EPetenko. Find NJ.com on Facebook.

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