Baby-proofed and bathed in natural light, the apartment had a lovely view of the Hudson River. The playgroup hostess had thoughtfully provided a packet of organic applesauce for each baby.   The talk quickly turned, as it often does with new parents in the same neighborhood, to pediatricians. One mom had found one she liked — not easy in this era of managed care and brusque manners. "But what is her stance on vaccinations?" our hostess inquired anxiously. "Uh, she's all for them," the first mother replied cautiously. After an uncomfortable silence, the hostess revealed that her sister had "a lot of education" about vaccines, and she herself was not planning to inject her child with any of that poison. "What about when she goes to school?" we asked, trying not to sound judgmental. Our hostess was unruffled. By that time, she asserted, so many people will be refusing vaccines, that the state laws — which currently require children attending public school or licensed daycare to have up-to-date shots — will have to be changed. "People," she explained, "are beginning to wake up."

People who don't vaccinate their kids tend to talk in these terms. They used to be passive "sheeple," doing what the doctors and the experts told them. Once they informed themselves, they realized the full horror of injecting helpless infants full of toxins. Kristen Monaghan, a stay-at-home mother in Manhattan's Gramercy neighborhood whose husband works in asset management, recalls that with her first child, Rubin (now twenty-one months), "I was afraid to educate myself." But when she was expecting her second, August, Kristen and her husband attended a talk by Dr. Larry Palevsky, a local anti-vaccine activist and As recently as our parents' generation, it was not unusual to see kids in wheelchairs or iron lungs: polio survivors.pediatrician. Kristen's husband was reluctant to go, assuming that Kristen was worrying needlessly. But she says that, during the break in the lecture, "We turned to each other and said, 'We've been such idiots.'"

Unlike many anti-vaccine activists, Dr. Palevsky comes across in conversation as a reasonable person. He talks about data and scientific "literature," not about government plots and cover-ups. "Parents become convinced," he explains, "that the risk of illness is worse than the risk of the vaccine. But there's no data to support that statement. There are no studies of the long-term effect of vaccinations." He later adds that there are no studies looking at the "real short-term effects of vaccinations, either." It is, of course, these kinds of statements that parents find most terrifying.

They're also pretty misleading; the