This article is from the archive of our partner National Journal

Most parents around the country already vaccinate their kids (the national vaccination rate for measles, mumps, and rubella was 94.7 percent). But a small, vocal, and often celebrity-represented, minority have chosen not to. For them, the future holds a worrying thought: the specter of California's mandatory vaccine law spreading across the nation.

"This was pushed through by lies and money," says Ginger Taylor, director of the Maine Coalition for Vaccine Choice. "It's not going to survive."

"I'm worried. I am." says Robert Murdoch, owner of Natural Family Physicians in Florida. "I don't' know how a civilized country can operate that way."

Dozens of bills aimed at stricter vaccination policies were brought before state legislatures across the country last year. Some came close. Most failed. But in the battle that has pitted parent opinion against public health, vaccine advocates say California's recent vaccine law may have provided what they need to start a national movement. 

"I'll tell you, there's been some growing momentum." - Diane Peterson, associate director of the Immunization Action Coalition

Catherine Flores-Martin's works with the California Immunization Coalition, the group that helped with California's law that requires all public and private school children in California to be immunized, regardless if their parents object. She says since Gov. Jerry Brown signed the bill last week, she's heard from groups and individuals across the country.

"We have not suggested to anyone, 'Oh, you could do this, too,' " Flores-Martin says, "It's more like we've been contacted by some states and asked how we organized ourself."

Last year in Disneyland, a measles outbreak infected 42 people. A tourist is believed to have brought it to the Annaheim, California, theme park, which spread to more than 130 people, many of whom were undervaccinated, or not vaccinated at all. That may have helped push the vaccination law through, as shortly after, newspapers across the state called for stricter immunization laws.

Next July, all children who attend California public or private schools will need to be vaccinated. The only exception is for medical reasons. If parents still refuse, they'll have to homeschool their kids.

But even even before the outbreak, there was a strong movement to mandate immunizations. California had already passed a law requiring parents who wanted to opt out to first consult a physician. It was one of the first laws like it, says, Diane Peterson, associate director of the Immunization Action Coalition. The law was designed to make it more difficult for parents who might have opted their kids out for convenience—say, they just moved, can't find their medical records, and need to enroll their child in school.

Advocates say that law decreased the California opt-out rate, which left only a small number of parents, some 3 percent in the state, who disagreed so vehemently with vaccines that nothing short of law could compel them.

And that's why advocates say the route that California took, a squeezing build-up to a mandated immunization, might be the way the rest of the country goes.

"I'll tell you," says Peterson, "there's been some growing momentum."

In the past year, Maine, Illinois, New York, Pennsylvania, and several other states tried to pass laws that would require parents to consult a physician or have a doctor sign off before they opted out. And bills in Vermont, Oregon, Washington, among others this year would have removed what's called philosophical or moral objections.

Advocates of required vaccines say parents who don't immunize their kids endanger public health. While the national vaccine rate might be high, there are pockets where many kids go unvaccinated. The areas that most commonly make the news are the posh, palm-lined neighborhoods of L.A., where the vaccination rates in some schools are said to be lower than some developing nations.

It's unprotected pockets like these, advocates say, that allow outbreaks. For a community to be safe, it needs to reach "herd immunity." Scientist believe this is around a 90 to 95 percent vaccination rate, which some entire states, like Colorado, Pennsylvania, and Arkansas, fall below.

When people opt out, vaccine advocates say, they endanger everyone. And that's how outbreaks like the one in Disneyland happen.

Then there are people like Robert Murdoch and Ginger Taylor. Both are the type of holdouts a national expansion of the California law would target.

Taylor, who runs an anti-vaccine organization in Maine, says her child grew sick after he received his immunizations. He vomited, had seizures, and ultimately his cognitive abilities regressed. Doctors later diagnosed him with autism. She blames the immunizations, and points to a 1998 study that links vaccines to autism. (The British journal that published that study later called it "a fraud," and its author was stripped of his medical license. Taylor insists the study was accurate.)

Murdoch runs a holistic family care center in Florida. He says his eyes opened after he received a tetanus booster in the 1990s. He grew sick, tired, and frail. Then he remembered how he'd felt the same way for years as a kid after he'd been vaccinated. He investigated for himself, and now believes in the danger of all vaccines.

"Just show me one that's safe and effective," Murdoch says.

For now, much of the work will be done on a state-by-state basis. And people like Peterson and Flores-Martin believe California will serve as the bellwether. So who might be next? Peterson says Vermont, Delaware, Illinois, and Connecticut all have pending legislation.

As for any national movement, there was a bill introduced into the U.S. House of Representatives in June. It's called the "Vaccinate All Children Act of 2015." It was introduced by a representative from Florida, Murdoch's home state. And that has him very worried.

This article is from the archive of our partner National Journal.

This article is part of our Next America: Higher Education project, which is supported by grants from the Bill & Melinda Gates Foundation and Lumina Foundation.

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