In 2022, a provisional total of 121 cases of measles from 6 states were reported to CDC. The sharply limited global travel and social interactions precipitated by the COVID-19 pandemic, which began in early 2020, also reduced the opportunities for introduction and transmission of measles, mumps, and rubella viruses in the United States. Current CDC measles surveillance updates can be found at www.cdc.gov/measles/cases-outbreaks.html.
Since the pre-vaccine era, there has been a more than 99% decrease in mumps cases in the United States. However, outbreaks still occasionally occur. In 2006, there was an outbreak affecting more than 6,584 people in the United States, with many cases occurring on college campuses. In 2009, an outbreak started in close-knit religious communities and schools in the Northeast, resulting in more than 3,000 cases. Since 2015, numerous outbreaks have been reported across the US, in college campuses, prisons, and close-knit communities, including a large outbreak in northwest Arkansas where almost 3,000 cases were reported in 2016. These outbreaks have shown that when people with mumps have close contact with a lot of other people (such as among residential college students and families in close-knit communities) mumps can spread, even among vaccinated people. However, outbreaks are much larger in areas where vaccine coverage rates are lower. A provisional total of 322 cases of mumps were reported to CDC in 2022.
Rubella was declared eliminated (the absence of endemic transmission for 12 months or more) from the United States in 2004. Fewer than 10 cases (primarily import-related) have been reported annually in the United States since elimination was declared. Rubella incidence in the United States has decreased by more than 99% from the pre-vaccine era. A provisional total of 3 cases of rubella, and no cases of congenital rubella syndrome, were reported in 2022.