The Health Department is warning of an ongoing outbreak of measles in Brooklyn's ultra-Orthodox Jewish communities, fueled in part by anti-vaccine propaganda promoted by religious leaders and organizations.

In the last month, officials have confirmed at least 17 cases of measles in ultra-Orthodox families in Williamsburg and Borough Park. That number is expected to rise, officials said, as additional cases are currently under investigation.

Twelve of the 17 victims did not receive the measles vaccination despite being eligible for it—a fairly common situation in a community suffering from widespread scare-mongering about the effectiveness of vaccines. Among the many sources of misinformation, a Jewish organization called Parents Teaching and Advocating for Children’s Health [PEACH] has been sending pamphlets to Orthodox homes promoting long-refuted conspiracy theories linking vaccines to autism. Rabbi William Handler, an ultra-Orthodox leader in Brooklyn, has also voiced support for the anti-vaxxer movement, and recently told Vox that parents who "placate the gods of vaccination" are engaging in "child sacrifice."

Measles, a highly contagious respiratory disease that can be fatal for small children, was declared eradicated from the United States in 2000. But the disease has periodically cropped up in tight-knit communities, including among the Amish in Ohio and the Somali-American population in Minnesota. In the last decade, opposition to vaccines in the ultra-Orthodox neighborhoods of Williamsburg, Borough Park and Crown Heights has led to occasional measles clusters, as well as a wave of whooping cough.

Provided by the Department of Health

To combat the spread of false information, the Health Department recently began targeting Orthodox newspapers, schools, and health care providers with an awareness campaign about the highly-infectious disease. Officials say they're already starting to see an increase in vaccination rates among the affected communities. But the isolation of the ultra-Orthodox enclaves, combined with their own close proximity and frequent trips out of the country, remains an obstacle to fully eliminating the disease.

"Parents who oppose vaccinations for measles and all other illnesses not only put their own children at risk, but endanger other children and families as well," said City Council Health Chair Mark Levine. "As Israel and other nations are facing outbreaks, the risk of measles affecting our New York communities is particularly acute in neighborhoods where international travel is common and frequent."

According to the Health Department, the initial Brooklyn case was acquired by children during a visit to Israel, where there is currently a major outbreak of the disease. The Orthodox community in Rockland County is also experiencing its own resurgence of measles, with at least 55 confirmed infections in recent weeks.

"As the measles outbreak continues to spread relentlessly, it is imperative that every member of our community protect themselves and their families by getting vaccinated," said Rabbi Avi Greenstein, Executive Director of the Boro Park Jewish Community Council.

"We need to take away the lesson of how important it is for every one of us to avail ourselves of modern medicine and not to trust in herd immunity, but rather to follow the vaccination schedule recommended by medical professionals to protect our families and our entire community."