PURPOSE: The purpose of this study was to investigate the potential relationship between MMR vaccination coverage and measles incidence in the US, as well as to examine the demographic characteristics and socio-economic status of unvaccinated individuals to determine if there are certain sub-populations who are routinely not receiving the MMR vaccine. METHODS/PROCEDURES: This retrospective cohort study determined the MMR vaccination coverage per year and compared it to the measles incidence for the same year. RESULTS: Results from this study suggest that regional differences in MMR vaccination rates spanning across multiple sub-populations are associated with the increasing measles incidence in the US. CONCLUSIONS: The correlations between MMR vaccination coverage and measles incidence in the US should be investigated further to determine what specific programs can be put in place to increase MMR vaccination rates state-wide and among vulnerable sub-populations.

Measles is a potentially deadly illness that has been declared no longer endemic in the United States of America since 2000.1 However, in the past few years, imported cases of the measles have continued to cause hospitalization and deaths among those citizens who remain unvaccinated, or have waning immunity, against measles, especially children. The Measles, Mumps and Rubella (MMR) vaccine has been available since 1963 and is routinely given to children in the first two years of life.1 Endemic cases of measles are increasing each year, specifically in undervaccinated communities. In 2018-2019, there was an outbreak of measles in the Williamsburg neighborhood of Brooklyn, New York. Investigating the knowledge, attitudes and opinions on the measles virus and the MMR vaccine in the Williamsburg neighborhood may facilitate discussions that could increase the vaccination rate among its population, as well as elucidate more effective strategies for vaccination in the future. Comparing attitudes from the Williamsburg neighborhood with a population across the Hudson River, in the East Village, which has previously had higher rates of vaccination, could shed light on how to target and tailor vaccination campaigns to different populations in New York City moving forward.2–4