New York

The 242 cases in New York (excluding New York City) included 206 in Rockland County and 36 in nearby counties. Most patients resided in orthodox Jewish neighborhoods with low school immunization rates. The median patient age was 5 years (range = 0 days* to 63 years). The 2017–2018 New York State School Immunization Survey measles vaccination rate for students in prekindergarten through grade 12 was 98%; however, documented measles vaccination coverage in schools in the outbreak area was only 77%. To prevent disease spread in schools, Rockland County and neighboring Orange County have excluded unvaccinated students from school for 21 days after a measles exposure. To further control spread after school exposures, in areas of Rockland County with measles cases, exclusions from school were expanded to include all nonimmune students at schools that had measles immunity rates of <95% as documented by 2 valid doses of measles-mumps-rubella vaccine (MMR) or serologic evidence of immunity. To provide opportunities for vaccination, approximately 20 community vaccination events open to all ages were held in Rockland County and two in Orange County.

During October 1, 2018–April 30, 2019, Rockland County administered 19,661 MMR doses. NYSDOH, RCDOH, and private medical providers held nine informational events and distributed educational materials focused on measles prevention to 45,000 homes. A culturally appropriate and detailed vaccine education book was distributed to 15,000 Rockland County and 10,000 Orange County homes and medical providers. Orthodox Jewish leaders were engaged in the outbreak response, with rabbinical leaders supporting vaccination efforts and community groups advocating for vaccination. As of April 30, 2019, transmission was ongoing. This has been the largest measles outbreak in New York (outside New York City) since 1992 and, at 7 months, the longest documented outbreak in the United States since endemic measles was eliminated in 2000 (2).