A measles outbreak is spreading within New York City’s Orthodox Jewish community, with 21 cases coming from a single yeshiva in Williamsburg, Brooklyn, according to city health officials.
The New York City Department of Health announced Thursday that 121 people have contracted measles since the outbreak began in October, and 31 cases have been newly identified. The vast majority of cases have affected children, particularly in the Borough Park and Williamsburg neighborhoods of Brooklyn. The outbreak’s initial case was acquired when a person visited Israel, where a measles outbreak is in progress, according to health officials.
Health officials have worked to promote measles vaccination in the Orthodox community, and in December required students at yeshivas in parts of Borough Park and Williamsburg to stay home from school if they had not received the full course of the measles, mumps and rubella (MMR) vaccine. There has traditionally been some resistance to vaccines in the insular Orthodox community, though health department representatives said the vaccination rate in this population is roughly equivalent to that in New York City as a whole. About 7,000 children in those communities were vaccinated due to the city’s campaign, health officials said.
But at least one yeshiva, Yeshiva Kehilath Yakov in Williamsburg, broke the city’s mandate in January and allowed an unvaccinated, but asymptomatic, student to return to school. The student turned out to have measles, resulting in 21 cases connected to this yeshiva alone, according to health officials.
Speaking with WNYC, the city’s Deputy Commissioner of Disease Control, Dr. Demetre Daskalakis, said that if the yeshiva had followed proper procedures, “the unvaccinated kid who got measles wouldn’t have been in the school and there wouldn’t have been a bunch of other [unvaccinated] students in the school and they wouldn’t have gotten measles. So we would actually be at closer to what would be the tail end of this outbreak.”
Representatives from the school did not immediately provide a comment to TIME.
Measles is a viral infection that causes symptoms including fever, runny nose, cough and a rash that affects the face and body. In severe cases, measles complications can include pneumonia, brain swelling and death. It’s highly contagious and is spread through the air. No one has died from New York City’s measles outbreak, through eight people have been hospitalized.
Measles was declared eradicated from the U.S. in 2000, but the disease is having a resurgence in several parts of the country — particularly in areas where vaccine resistance is common, including some pockets of the Pacific Northwest.