When I first heard that the measles outbreak in New York was particularly bad among Orthodox (actually, ultra-Orthodox) Jews, I assumed it was because of some religious prohibition about vaccines in that group. That’s also what I read here and there in comments around the blogosphere.
But apparently it’s not true. There is no conflict between traditional Jewish law and vaccinations, even among the strictest sects.
So, what’s going on? It’s not easy to get an answer. But here’s an exceptionally interesting article:
… a careful look at the data available on vaccination rates in Orthodox Jewish communities, and reports by members of the community and their doctors, indicate that the Hasidic community is vaccinated on par with the rest of the city…
…[T]he vaccination rate [in Chasidic communities is] around 96 percent. The threshold for herd immunity for measles is presumed to be 93 to 95 percent.
That information also is supported by Jane Zucker, New York City’s assistant commissioner of the Bureau of Immunization. Zucker told Vox that most school-age children in the community are vaccinated at levels on par with other schools…
OJPAC also noted in a statement that in upstate Rockland County, where the Orthodox community is also in the midst of a measles outbreak, most schools now have a 95 percent vaccination rate for measles. One yeshiva had 100 percent compliance, as reported by health officials early in the outbreak.
So what really is going on?
The answer may lie in a combination of factors, including the large numbers of young children, delays in receiving the MMR, and vaccine failure.
OJPAC notes that large family size and frequent mingling during holiday and other events create an environment conducive to spreading an infection that is not present in other segments of society.
It’s worth noting here that the CDC has reported more than 400 cases of mumps in 34 states this year and that these outbreaks can occur in highly vaccinated populations, especially where people are in close contact with one another.
There’s also evidence that there’s a higher rate of delay in vaccination in this community:
“Williamsburg … has one of the lowest rates of vaccine coverage among young children, ages 19 to 35 months, in the city,” wrote Belluz.
Zucker told Vox, “We hear they want to wait until the child is older so they know the child doesn’t have autism, then get the child vaccinated.”
But that’s true in all communities these days—just thank the anti-vaxers.
There there’s this:
Another piece of the puzzle is vaccine failure. Recent data from the health department confirms that a known minority of cases are found in vaccinated people…
…[M]ultiple studies show that even two doses of measles vaccine do not appear to confer immunity in 2 to 10 percent of people, a phenomenon called primary failure. Secondary failure refers to the waning of immunity over time.
“Thus, measles outbreaks also occur even among highly vaccinated populations because of primary and secondary vaccine failure, which results in gradually larger pools of susceptible persons and outbreaks once measles is introduced.
But isn’t it much more attention-getting to blame the Orthodox Jews? Just to take one of many examples, this article seems to insinuate (without actually saying so, and without giving any hard facts, unlike the other article) that orthodoxy is to blame. This one, also from the Times, and headlined “‘Monkey, Rat and Pig DNA’: How Misinformation Is Driving the Measles Outbreak Among Ultra-Orthodox Jews,” talks a great deal about an anti-vaccine pamphlet being circulated among ultra-Orthodox Jews without giving the figures that in fact vaccination rates are typical among them, not atypical.
Even without articles like that, that’s a conclusion many people will come to on their own, erroneously—just as I initially did.

