This graph comes from the Washington Post. Before 1993 there were many US measles cases, mainly due to waning of vaccine-induced immunity. Then an additional MMR dose was added to the vaccine schedule in the US, and measles immunity improved. There is no endemic measles in the US, helped by the fact there is no animal reservoir.
People who are incubating cases of measles, and are infectious, continue to enter the US from abroad. This caused 23 separate outbreaks in the US in 2014. However, there is very reduced measles transmission within the US, due both to high levels of immunity and careful case-finding by public health workers, who recommend quarantines, vaccinations or use of immune serum when necessary. There have been no deaths from measles in the US since 2003.
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