Hurts for a second, helps for a long time
Bloomberg; Bloomberg via Getty Images
By Jeffrey Kluger
May 15, 2015
Kluger is Editor at Large for TIME.

Science and religion have not always gotten along—especially when it comes to medicine. If you believe your body is a temple and your faith can keep you well, you don’t take kindly to doctors telling you how to look after yourself and your family. If you believe faith is fine but it’s medicine that saves lives, you frown on people who endanger themselves—and their children—by resisting scientific progress.

When it comes to vaccines, however, both camps—with the help of lawmakers—had reached a workable truce. All states require children to be vaccinated to attend school, and all states also provide exemptions for the small share of kids who, for legitimate medical reasons, can’t be vaccinated. All states but Mississippi and West Virginia have also allowed parents with religious objections to opt out of the vaccination rules.

It’s undeniable that that can put their kids at risk. By definition, the child who is vaccinated against polio will not contract the disease and the child who’s not vaccinated possibly could. But that possibility can be a remote one, thanks to what’s known as herd immunity. As long as about 95% of a population is vaccinated against a particular disease, it’s exceedingly difficult for a virus to find enough holes in that herd to reach the few people who aren’t protected. And since religious opt-outs had been relatively rare, the system worked.

But that’s all changed, thanks to what’s known as the philosophical or personal belief exemption, an expansion of the no-vax loophole allowing parents to refuse vaccinations for pretty much any reason at all—they don’t like the state telling them what to do, or they can’t be bothered by all those trips to the doctor, or they’ve read something on the Internet that about how vaccines are a mortal health peril, despite the fact that that virtually every medical authority on the planet assures them that that’s not so. Call it a personal belief and you get a free pass. This has done very bad things to the herd.

Many states like Colorado and California, which have easy opt-out rules, have fallen below the 95% compliance levels needed to keep their populations healthy, and recent outbreaks of measles in New York City, mumps in Columbus, Ohio, and whooping cough in California directly correlate with poor vaccination levels. A multistate measles outbreak in the southwest that is only now subsiding was similarly linked linked to a single infected person who visited Disneyland and spread the virus among unvaccinated visitors there.

Meantime, states with high vaccination rates are experiencing few of these problems. Most notable among them are Mississippi and West Virginia, which have neither religious nor philosophical opt-outs and thus have first-in-the-nation vaccine compliance levels of 99.9%.

Now some states are pushing back. As TIME reported, the California state Senate has just advanced a bill to eliminate both philosophical and religious exemptions, leaving only demonstrated medical problems as a reason for parents to refuse vaccines. Legislators who opposed the bill objected to eliminating the religious exemption, and their argument does have merit. Not only does the new bill raise First Amendment issues, statistics also make it clear that it’s not the faith community that’s causing most of the trouble. According to the New England Journal of Medicine, states that have a personal belief exemption have 2.54 times the vaccine refusal rate of states that have only the faith exemption. Left to themselves, the religious refuseniks would not be causing too much of a problem

But California legislators know the population they’re dealing with. Anti-vaxxers are like water, flowing to the nearest handy opening. Close off the personal belief portal, and they’ll just slosh over to the religious side, claiming a sudden spiritual epiphany that excuses them from vaccinating. The only way to keep kids safe is to close both exit routes.

The victims in all this are the truly devout. Lawmakers have long made clear that not all religious objections to medical procedures will be tolerated, particularly when it comes to the welfare of minors. Parents who cite religious beliefs in refusing to treat a child for, say, leukemia will likely lose that child to the state, which will provide the necessary care.

In the case of vaccines, however, there is—or was—a workaround. With the thinning of the herd, however, religious practices have to come second to saving the lives and health of babies. People of faith may resent the states, but if blame is to be laid, it belongs to the anti-vaxxers. They’re a crowd that’s always excelled at making avoidable messes, and they’ve just added one more to their long and growing list of them.

Write to Jeffrey Kluger at


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