Measles Cases and Outbreaks
Updated on April 12, 2024. CDC updates this page weekly on Fridays.
Measles vaccine
Prevent measles and talk to your healthcare provider about the measles, mumps, and rubella (MMR) vaccine, especially if planning to travel.
Measles and travel
Did you know that measles can be found around the world?
As of April 11, 2024, a total of 121 measles cases were reported by 18 jurisdictions: Arizona, California, Florida, Georgia, Illinois, Indiana, Louisiana, Maryland, Michigan, Minnesota, Missouri, New Jersey, New York City, New York State, Ohio, Pennsylvania, Virginia, and Washington.
There have been 7 outbreaks (defined as 3 or more related cases) reported in 2024, and 71% of cases (86 of 121) are outbreak-associated. For comparison, 4 outbreaks were reported during 2023 and 48% of cases (28 of 58) were outbreak-associated. For more information on the ongoing outbreak in Chicago, Illinois see the Chicago Department of Public Health Measles Update.
U.S. Cases in 2024
Total cases
121
|
| Age
Under 5 years: 57 (47%) |
| Vaccination Status
Unvaccinated or Unknown: 82% |
U.S. Hospitalizations in 2024
56%of cases hospitalized (68 of 121 cases) for isolation or for management of measles complications. |
| Percent of Age Group Hospitalized
Under 5 years: 65% (37 of 57)
|
Number of measles cases reported by week
2023-2024* (as of April 11, 2024)
Note: rash onset date is currently unknown for three reported cases in 2024.
Measles Cases Reported in 2024
as of April 11, 2024
Number of measles cases reported by year
as of April 11, 2024
*2023-2024 case counts are preliminary and subject to change.
History of Measles Cases
Measles was officially eliminated from the United States in 2000, meaning there is no measles spreading within the country and new cases are only found when someone contracts measles abroad and returns to the country. Achieving measles elimination status in the U.S. was a historic public health achievement. The below figure illustrates how common measles was before vaccines and how vaccine policy enabled elimination.
*2023 data are preliminary and subject to change.
†Elimination is defined as the absence of endemic measles transmission in a region for ≥ 12 months in the presence of a well-performing surveillance system.
MMR Vaccine Coverage for Kindergarteners by School Year (2009-2023)
The Measles, Mumps, Rubella (MMR) vaccine is very safe and effective. When more than 95% of people in a community are vaccinated (coverage >95%), most people are protected through community immunity (herd immunity). However, vaccination coverage among U.S. kindergartners has decreased from 95.2% during the 2019–2020 school year to 93.1% in the 2022–2023 school year, leaving approximately 250,000 kindergartners at risk each year over the last three years. To dive into vaccine coverage data for MMR, visit VaxView | CDC.
At local levels, vaccine coverage rates may vary considerably, and pockets of unvaccinated people can exist in states with high vaccination coverage. When measles gets into communities of unvaccinated people in the U.S., outbreaks can occur.
Previous Years
Measles cases in 2023
During January 1-December 31, 2023, a total of 58 measles cases were reported by 20 jurisdictions: California, Colorado, District of Columbia, Florida, Hawaii, Idaho, Illinois, Kentucky, Maryland, Missouri, New Jersey, New York City, Ohio, Oregon, Pennsylvania, Texas, Utah, Virginia, Washington, and Wisconsin.
Measles cases in 2022
From January 1 to December 31, 2022, a total of 121 measles cases were reported by 6 jurisdictions. *
Measles cases in 2021
From January 1 to December 31, 2021, a total of 49 measles cases were reported by 5 jurisdictions. *
Measles cases in 2020
From January 1 to December 31, 2020, 13 individual cases of measles were confirmed in 8 jurisdictions.*
*Jurisdictions refer to any of the 50 states, New York City, and the District of Columbia.
Measles cases in 2019
- From January 1 to December 31, 2019, 1,274 individual cases of measles were confirmed in 31 states.
- This is the greatest number of cases reported in the U.S. since 1992. The majority of cases were among people who were not vaccinated against measles. Measles is more likely to spread and cause outbreaks in U.S. communities where groups of people are unvaccinated.
- For more information please see the following reports:
- Increase in Measles Cases – United States, January 1-April 26, 2019 MMWR. May 3, 2019
- National Update on Measles Cases and Outbreaks – United States, January 1-October 1, 2019. MMWR. October 11, 2019