Measles Map Shows States With Reported Cases in 2024

Cases of measles have been recorded in at least 11 U.S. states since the start of the year, as local health officials attempt to prevent the spread of the disease.

There have been confirmed cases in parts of California, Delaware, Florida, Georgia, Pennsylvania, Maryland, Missouri, New Jersey, New York, Ohio and Washington. Officials are investigating whether others who had close contact with those infected may have contracted it as well.

Measles is a highly contagious illness caused by a virus that spreads through an infected person's breath, coughs or sneezes. Symptoms tend to include a cold-like illness and a rash of tiny red spots. However, it can cause complications and, in some cases, lead to death.

The latest area to see an outbreak linked to an elementary school is Broward County in Florida, where six people were diagnosed with measles earlier this week. The first case was detected in a third grader with no history of travel who tested positive on February 16.

The state's Surgeon General Joseph Ladapo attracted criticism for deferring to parents as to whether to send their children to school, citing the area's high vaccination rate. This is in contrast to Centers for Disease Control and Prevention (CDC) guidance that unvaccinated students must be excluded from school.

Cases have also been recorded in New York City, according to the CDC. The New York State Department of Health has said that there were no cases in the state outside of the city.

On February 3, the director of the Ohio Department of Health reported the state's first case of 2024, in a child from Montgomery County, which includes the city of Dayton. The department said at the time it wasn't aware of any additional cases, but it was working to identify others who may have been exposed.

On February 1, the Maryland Department of Health confirmed a positive case in a Montgomery County resident who traveled internationally prior to becoming infected.

Also on February 1, the Los Angeles County Department of Public Health in California announced that a resident had contracted the illness and had traveled through Los Angeles International Airport in the afternoon of January 25.

On January 18, the Georgia Department of Public Health confirmed a case of measles in an unvaccinated resident of the Atlanta area, who was exposed to it abroad. On January 12, health officials in Clay County, Missouri, also confirmed a case of measles in a Liberty resident, following travel via Kansas City International Airport.

Prior to that, on January 11, the Delaware Division of Public Health announced that 20 to 30 people may have been exposed to someone who had been at the Nemours Children's Hospital in Wilmington and wasn't showing symptoms of the disease, but was infectious, on December 29, 2023.

On January 13, the Camden County Health Department in New Jersey said it was "closely monitoring" a confirmed case of measles in the area who had visited two nearby health care facilities earlier in the month.

Health officials in Philadelphia, Pennsylvania, have been tracking an outbreak of measles in the city. As of January 22, there had been nine confirmed cases. One of those cases was in nearby Montgomery County.

Officials in Washington state said that, as of January 6, six epidemiologically connected cases of measles had been identified in Clark and Wahkiakum counties. They stressed that the risk to the public was deemed low and the infections likely occurred in mid to late December.

Health officials in the U.S. urged people to get the MMR vaccine. One dose is 93 percent effective at preventing measles, while two doses are 97 percent effective.

Figures compiled by the CDC show, as of February 15 this year, there have been 20 new cases of measles reported in the U.S., excluding those recorded in Florida this week.

The worst year for measles in the U.S. since 1992 came in 2019, when there were 1,274 cases recorded nationwide.