The Centers for Disease Control just announced that 2012 will most likely be a record year for whooping cough — perhaps the worst in five decades. To date, 18,000 cases of the potentially fatal illness have been reported, more than twice as many as at this point last year, and New York has among the highest rates.

Why the spike? It’s not entirely clear, but it looks like the vaccine is wearing off too soon.

The vaccine for whooping cough, also known as pertussis, is given to kids between age 4 and 6, usually with a booster at 11. But vaccine makers changed their formula in the 1990s, and the new vaccine seems to last fewer years than the old.

Why reformulate? As USA Today reported recently, “Unproved and unscientific claims that there was a connection between the pertussis vaccine and brain injury pushed manufacturers to switch.”

So manufacturers changed their vaccines because of rumors and hysteria. And the result seems to be more cases of whooping cough and more fatalities from a disease we know how to prevent.

Where’s the outrage?

A few months ago, some acquaintances of mine were discussing on Facebook whether to give their children the MMR (measles, mumps, rubella) vaccine, because they’d heard it could cause autism, Asperger’s syndrome and Attention Deficit Disorder.

There’s no evidence for any of those claims. But a number of commenters on the thread had decided to delay giving their children the next dose. And then my children got invited to one of those kids’ birthday parties.

It’s crazy enough that you want to put your own kids at risk, but now you want to put my kids in harm’s way, too?

Vaccines work through “herd immunization.” If enough of the population is vaccinated, then the disease becomes so rare that even those who aren’t vaccinated — like babies who haven’t yet had their full course of shots — won’t catch it. But as soon as the vaccination percentage falls below a certain level, the weakest members of our population will start to suffer the effects.

Medical experts are now concerned about measles outbreaks across the country, particularly in the Northwest, but also in Miami, San Diego and rural Pennsylvania. Two people even contracted it at this year’s Super Bowl. Many of these outbreaks can be traced back to kids whose parents had done “research” and decided not to vaccinate their children.

They’re typically the wealthy and “well-educated.” And they use so-called religious exemptions in the law in order to get around these state-mandated vaccines. Whether these exemptions should exist in matters that concern immediate public-health risks is questionable, but it’s clear that the exemptions are being abused.

When I called my pediatrician to ask whether my kids should attend the aforementioned birthday party, I could practically hear him tearing his heart out on the other end of the line.

I recently heard a mother lecturing another doctor in the practice about how her child simply couldn’t have more than one shot at an appointment: She’d heard it was “bad for him.”

Bad for him? Is it worse than measles or whooping cough?

Doctors have become so frustrated that some have simply stopped seeing kids who aren’t vaccinated. That’s understandable, though it does raise certain ethical questions about the kids who may go untreated.

There’s a better and potentially more effective way to solve this problem: social pressure.

It’s time for sane parents to put an end to this nonsense. Start a chapter of Mothers Against Bad Science (MABS, if you like) and make clear to any parents who haven’t fully vaccinated their children that you’re cutting them off. It’s not worth another goody bag.

Naomi Schaefer Riley writes frequently on religion, education and culture.