This June, a young man from Rockland county, New York, went to the emergency room. He’d been feverish for five days and was suffering from a stiff neck, pain in his back and abdomen, and constipation. Even more concerning, for two days his legs had been abnormally weak. Doctors suspected the man had acute flaccid myelitis – muscle weakness caused by inflammation of the spinal cord, typically stemming from a viral infection. Lab tests revealed a shocking diagnosis: the culprit was the poliovirus.
Throughout the first half of the 20th century, thousands of children died or were paralyzed due to polio; there were 20,000 cases of polio-induced paralysis in 1952 alone. Polio’s eradication from the US in 1979 thanks to vaccines is one of the greatest achievements of modern medicine. In the 21st century, there had been just three known instances of polio in the US – all thought to be imported – affecting a total of 10 people, with only one involving community spread.
Alerted to the man’s diagnosis, public health experts from the CDC, the New York health department and Rockland county sprang into action. Through wastewater testing, they discovered that the poliovirus had been circulating in Rockland county since May. They also found it in wastewater from neighboring Orange county and New York City. By mid-August, it became clear that not only was this the second case of polio from community transmission since 1979, it was probably a “silent outbreak” that had infected hundreds.
How did this happen?
Polio’s return to the US resulted from the confluence of a complicated set of scientific and societal factors that allowed a mutated version of the virus to start circulating in a susceptible community. This is the story of a life-saving vaccine with an unfortunate loophole that produced that version of the virus, and a calculated anti-vaccine campaign that created a vulnerable population.
The poliovirus found in New York is not the same virus that once ripped through urban communities. Thanks to vaccination, that original, “wild” poliovirus has been eliminated from all but two countries: Pakistan and Afghanistan. But paradoxically, most polio cases that emerge nowadays – including the one infecting the man from Rockland – are derived from the vaccine itself.
There are two types of polio vaccine, both developed during the 1950s. The oral polio vaccine, created by Albert Sabin, uses a live, weakened form of the virus to induce immunity. It is not dangerous to the person who receives it; the virus cannot pass from the patient’s gut to their spinal cord, where it could cause paralysis.
But the weakened vaccine virus can acquire mutations that turn it into a live virus. As a result, for a few weeks after someone receives the vaccine, they excrete infectious, vaccine-derived poliovirus. Vaccine-derived poliovirus poses no threat to vaccinated people. But anyone unvaccinated is at risk.
Since the Covid pandemic, the pool of unvaccinated, vulnerable people has grown. The oral polio vaccine is typically used in developing countries because it is easier to administer and can be stored at room temperature. But just like everything else during the pandemic, campaigns using the oral polio vaccine were disrupted. So far this year, there have been an estimated 20 outbreaks occurring around the world, all from vaccine-derived poliovirus.
The other type of polio vaccine, developed by Jonas Salk, uses an inactivated version of the virus. While that vaccine is safer – a dead virus can’t mutate and come back to life – it doesn’t provide as robust protection. Because the oral vaccine travels through the gut, it offers local immunity there and prevents the vaccinated person from becoming reinfected. The inactivated vaccine, which is delivered via injection, stimulates an immune response that stops the virus from damaging neurons and causing symptoms but doesn’t actually prevent infection.
Since 2000, the inactivated polio vaccine has been used exclusively in the US. That means the current outbreak originated somewhere the oral polio vaccine is used, and was unwittingly brought into the US by a person who didn’t know they were infected. (Experts don’t yet know where from.) It also means that much of the vaccine detected in the wastewater in New York is probably from vaccinated people infected with vaccine-derived virus but who don’t have any symptoms and aren’t at risk of paralysis.
“A virus that reverted from the vaccine emerged from a kid that was vaccinated, and because other humans that were around were not vaccinated or resistant to the virus, the virus has started to take hold in the human population,” explains Raul Andino, a professor of microbiology and immunology at the University of California, San Francisco. “This case of imported virus came into New York and took hold in the whole population because everybody’s susceptible to infection … Basically, we have a silent epidemic, and that doesn’t cause a problem until somebody is not vaccinated.”
Just up the Hudson River from New York City lies Rockland county, where a handful of villages and small towns are notable for two things: having one of the largest populations of ultra-Orthodox Jews in the country, and extraordinarily low vaccination rates. Those low rates – only 37% in one zip code – created precisely the kind of host community that Andino said the poliovirus could exploit.
They’re also not an accident. Low vaccination rates in Orthodox communities across New York are the result of an organized campaign waged by national anti-vaccine groups for years.
Vaccine hesitancy is not characteristic of Orthodox Judaism. The vast majority of rabbis and Jewish scholars interpret several passages in the Torah and other Jewish texts as being supportive of vaccines.
“This is not an Orthodox Jewish problem. In most Orthodox Jewish neighborhoods, it’s 100% vaccination,” says Aaron Glatt, chief of infectious diseases at Mount Sinai South Nassau and an Orthodox rabbi. “The Jewish religion mandates you to get vaccinated, as far as I’m concerned. That’s my official opinion as a rabbi. I tell my congregation, you have to get vaccinated. That’s the Jewish way of protecting lives.”
Orthodox mothers in Israel who choose not to vaccinate their children acknowledge that they are doing so against the advice of their rabbis, according to a 2021 paper published in the Journal of Religion and Health. Their motivations resemble those of other vaccine-hesitant parents, often rooted in standard anti-vaccine messaging, such as being “more afraid of the vaccines than of the diseases”.
“I think that there are people that may not be fully well connected to accurate information, and they are preyed upon by individuals that know exactly how to take advantage of these populations,” says Glatt. “And it’s across all ethnic groups; it’s across all religions.”
Indeed, anti-vaccine pockets have sprouted up across the US – some organic, others seeded by national groups – including in wealthy, liberal enclaves in Marin county, California; Portland, Oregon; and Clark county, Washington, as well as in an Amish community in Ohio and among Somali refugees in Minnesota.
Questions about vaccines started to emerge in the early 2000s with a new generation of parents who had no first-hand knowledge of vaccine-controlled diseases such as measles and polio, says Saad Omer, director of the Yale Institute for Global Health. “In the minds of successive cohorts of parents, the salience of real or perceived side effects go up compared to the salience of actual disease,” Omer says. “That happened over several decades because vaccines were so successful in controlling polio in the US.”
Seizing this opportunity, national anti-vaccine groups became aggressive evangelizers, and their messaging has taken hold in communities that Omer says share several common traits, such as having strong values of purity (either secular or religious) and liberty – a combination of “my body is a temple” and “you can’t tell me what to do”.
An outbreak becomes likely when these groups – which are often tight knit and insular – have frequent outside exposures, particularly through travel. For example, a measles outbreak occurred among the Ohio Amish community when two unvaccinated members contracted the virus while visiting the Philippines (reports conflict as to whether the trip was for charitable or missionary purposes).
Experts interviewed for this article weren’t sure when vaccine hesitancy initially emerged in the Rockland Orthodox community. The first organized action appears to have been a phone hotline through which anti-vaccine activists “would promote a lot of misinformation” to parents with questions about vaccination, says Dorit Reiss, a professor at the University of California Hastings College of Law.
The movement gained traction in the mid-2010s with the publication of the Vaccine Safety Handbook, put out by an anti-vaccine group called Parents Educating and Advocating for Children’s Health. Commonly known as the Peach pamphlet, the material was distributed to Jewish communities throughout New York and into Pittsburgh.
The handbook promotes standard anti-vaccine messaging, but “everything has a Jewish flavor to it,” says Miriam Knoll, co-founder and chief executive of the Jewish Orthodox Women’s Medical Association (Jowma). “It used a lot of Jewish wording and ideas to make things up about [vaccines].”
No one knows who funded the effort or why, although Reiss says Barbara Loe Fisher, head of the National Vaccine Information Center (the country’s oldest anti-vaccine organization), and Moishe Kahan, a member of the local Orthodox community who sells supplements, were among the names credited with writing the handbook. “This is a collaboration between local anti-vaccine activists and the National Vaccine Information Center, and it’s a very misleading pamphlet,” says Reiss.
The consequences of the campaign became clear in 2018 when an unvaccinated child contracted the virus on a trip to Israel and triggered a measles outbreak in New York. Israel has a high national vaccination rate (upwards of 97%), but some Orthodox communities in the country have also absorbed anti-vaccine messaging. Measles and polio outbreaks – including the current one – have occurred simultaneously in both countries.
The New York measles outbreak ultimately affected 649 people, 93% of whom were Orthodox Jews. The situation attracted national attention and intensified campaigns from both sides of the issue. Rallies held in Rockland and Brooklyn in 2019 featured Andrew Wakefield, the disgraced British scientist who started the fraudulent claim that vaccines cause autism, and former Hollywood producer Del Bigtree, who directed the documentary Vaxxed: From Cover-Up To Catastrophe and is now chief executive of the anti-vaccination group Informed Consent Action Network.
In response, a group of Orthodox Jewish nurses formed Emes, which stands for Engaging in Medical Education with Sensitivity, and also means “truth” in Yiddish. They put out a rebuttal to the Peach handbook entitled “A Slice of Pie: Parents Informed and Educated”. A local Orthodox businessman also funded a pamphlet, printed in English and Yiddish, that quoted prominent Orthodox rabbis explaining how the Torah supports vaccination. The state of New York stepped in too, officially removing the religious exemption to school vaccine mandates in 2019.
Thanks to these types of efforts, public health groups started “making progress” in counteracting anti-vaccine sentiments across the country, Omer says. But then the Covid pandemic hit.
Recent data revealed that childhood vaccination rates have declined worldwide since 2020 – the biggest backslide in 30 years. The reason is probably twofold: first, reduced access to routine pediatric appointments disrupted vaccination schedules, particularly in east Asian and Pacific nations. Second, at least in the US, growing distrust of government public health agencies and the spread of anti-vaccine talking points has taken a toll.
Knoll says that, anecdotally, physicians who serve the Orthodox Jewish community are seeing parents who “were never anti-vax, always vaccinated their kids with all routine pediatric vaccines, but now with their younger kids, they’re very hesitant to vaccinate. Why? Because of distrust sowed through the pandemic.”
However, she also says that the paralyzed young man in Rockland appears to have served as a wake-up call for many parents. A Jowma colleague of Knoll’s who works in Rockland county reported that in the past week, “half of her patients were people who came in for a polio vaccine”.
Knoll says that when asked why they didn’t come in sooner, the parents’ most common response was: “It just wasn’t a priority.” But once they heard about the case, “they got scared, so they came in.”