An exploration of measles vaccination, mortality, and
outbreak trends in the United States, 2003-2015.
Measles was officially declared eliminated from the United States in 2000 due to the widespread success of the measles vaccine. In many countries around the world, however, measles still represents a serious problem. According to the World Health Organization, deaths worldwide associated with the disease have dropped significantly in recent years, but global mortality rates give us a sobering perspective into what can be a highly deadly disease.
The MMR vaccine is used to prevent measles, mumps, and rubella, and is generally first administered to children at the age of 12-15 months. Here, we sampled data from the National Immunization Survey (NIS) to understand the vaccination coverage of children 19-36 months in the United States, who are expected to have already received their first dose. Herd immunity, the phenomenon by which the community has enough immune indiviudals to resist infection, generally requires 90-95% vaccination.
In the past 10 years, the United States' average immunization rate has been in this range, but there are some pockets that are way under the herd immunity range and at risk for outbreaks. Colorado's rate is quite low, and both Ohio and Connecticut's rates have been dropping. On the other hand, New Hampshire's rate has been consistently above that required for herd immunity over the past few years. Mississippi and West Virginia are the only states that allow only medical (and not religious or philosophical) exemptions from vaccination for students attending public school - interestly, they have quite high rates of vaccination for kindergarten students, but not necessarily for toddlers!
Measles outbreaks are more than just a statistic: they're a story. We've curated all of the measles-related articles from the CDC's Morbidity and Mortality Weekly Report (MMWR) in order to provide a comprehensive visualization of measles outbreaks in the United States since 2003. Hover over each of the outbreaks to get our summarization of the corresponding CDC report. It's interesting that many measles outbreaks are centralized around religious communities! Note, too, that each outbreak is tied to a particular location abroad: with measles officially declared eliminated from the United States, new cases must be brought in from overseas.