Measles Cases and Outbreaks
Updated on April 19, 2024. CDC updates this page weekly on Fridays.
As of April 18, 2024, a total of 125 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 69% of cases (86 of 125) 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
125
|
| Age
Under 5 years: 57 (46%) |
| Vaccination Status
Unvaccinated or Unknown: 83% |
U.S. Hospitalizations in 2024
54%of cases hospitalized (68 of 125 cases) for isolation or for management of measles complications. |
| Percent of Age Group Hospitalized
Under 5 years: 65% (37 of 57) |
Weekly Measles Cases by Rash Onset Date
2023-2024* (as of April 18, 2024)
Note: rash onset date is currently unknown for one reported case in 2024, which is not included in this figure.
Measles Cases in 2024
as of April 18, 2024
Yearly Measles Cases
as of April 18, 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
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.
From January 1 to December 31, 2022, a total of 121 measles cases were reported by 6 jurisdictions. *
For more information please see the following reports:
- Notes from the Field: Measles Outbreak — Central Ohio, 2022–2023
MMWR. August 4, 2023
From January 1 to December 31, 2021, a total of 49 measles cases were reported by 5 jurisdictions. *
For more information please see the following reports:
From January 1 to December 31, 2020, 13 individual cases of measles were confirmed in 8 jurisdictions.*
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
- National Update on Measles Cases and Outbreaks — United States, January 1–October 1, 2019
MMWR. October 11, 2019 - Notes from the Field: Community Outbreak of Measles — Clark County, Washington, 2018–2019
MMWR. May 17, 2019 - Notes from the Field: Measles Outbreaks from Imported Cases in Orthodox Jewish Communities — New York and New Jersey, 2018–2019
MMWR. May 17, 2019
From January 1 to December 31, 2018, 382 individual cases of measles were confirmed in 28 jurisdictions.*
For more information please see the following reports:
- Measles Outbreak — Minnesota April–May 2017
MMWR. July 14, 2017
For more information please see the following reports:
For more information please see the following reports:
- Measles — United States, January 4–April 2, 2015
MMWR. April 17, 2015 - Measles Outbreak — California, December 2014–February 2015
MMWR. Feb 20, 2015
For more information please see the following reports:
- Measles Outbreak in an Unvaccinated Family and a Possibly Associated International Traveler — Orange County, Florida, December 2012–January 2013
MMWR. Sep 12, 2014 - Notes from the Field: Measles in a Micronesian Community — King County, Washington, 2014
MMWR. Sep 12, 2014 - Measles — United States, January 1–May 23, 2014
MMWR May 29, 2014 - Notes from the Field: Measles — California, January 1–April 18, 2014
MMWR. Apr 25, 2014
For more information please see the following reports:
- Measles — United States, January 1-August 24, 2013
MMWR. Sep 13, 2013 - Notes from the field: Measles outbreak among members of a religious community — Brooklyn, New York, March–June 2013
MMWR. Vol 62, No 36;752-3 09/13/2013 - Notes from the field: Measles outbreak associated with a traveler returning from India — North Carolina, April–May 2013
MMWR. Vol 62, No 36;753
*Jurisdictions refer to any of the 50 states, New York City, and the District of Columbia.