Editor’s note: For more AAP News coverage of the measles outbreak, visit https://bit.ly/Measles2025.
Confirmed measles cases in the U.S. increased 12.4 percent in one week, with the Centers for Disease Control (CDC) and Prevention now reporting 800 confirmed cases.
The total number of cases, reported April 18 by the CDC, is an increase of 88 cases since the agency’s last update one week prior. The total is likely an undercount as it may represent only those ill enough to seek medical care. Of the total, 96% are unvaccinated or individuals whose vaccine status is unknown.
The outbreak includes three deaths. Two of the deaths were unvaccinated school-age children in Texas who had no underlying conditions. They are the first measles-related deaths in the U.S. in a decade.
“As pediatricians, we grieve for the loss of every child,” said Valerie B. Smith, M.D., M.P.H., FAAP, president of the Texas Pediatric Society (AAP Texas Chapter). “Pediatricians in west Texas and surrounding states where the outbreak has spread are working diligently to stop the spread of measles in their community through vaccination and to treat children who are ill. We are indebted to them for their tireless commitment to their community.”
Eighty-five people have been hospitalized with measles this year, including 47 children under 5 years of age and 21 children between the ages of 5 and 19 years.
There have been 10 outbreaks (defined as three or more related cases) with 94% of the confirmed cased being outbreak-associated. Measles cases have been reported in 25 jurisdictions: Alaska, Arkansas, California, Colorado, Florida, Georgia, Hawaii, Indiana, Kansas, Kentucky, Maryland, Michigan, Minnesota, New Jersey, New Mexico, New York City, New York state, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont and Washington.
The CDC count does not include the state of Montana, which is reporting the state’s first case of measles since 1990. According to the Department of Public Health and Human Services and the Gallatin City-County Health Department, five cases have been confirmed in Gallatin County. All five are either unvaccinated or have an unknown vaccine status and were exposed to measles while traveling outside of Montana.
The state of Michigan confirmed a measles outbreak in Montcalm County, the state’s first outbreak since 2019. There have been seven total confirmed measles cases in the state this year, according to the Michigan Department of Health and Human Services.
The largest outbreak continues in west Texas near the New Mexico border. The Texas Department of State Health Services has reported 597 cases of measles as of April 18, an increase of 36 cases since its previous update three days prior. Gaines County has reported more than 62% of the state’s total cases. New Mexico has reported 63 measles cases, with 59 of those in Lea County, which borders Gaines County.
The AAP and CDC recommend health care professionals ensure all patients are up to date on measles-mumps-rubella (MMR) vaccination to prevent infection and spread. The first dose is given at 12-15 months of age, and the second is given at 4-6 years of age. One dose of MMR is 93% effective against measles, and two doses are 97% effective.
The measles virus is transmitted by contact with infectious droplets or by airborne spread when an infected person breathes, coughs or sneezes. Measles virus can remain infectious in the air up to two hours after an infected person leaves an area.
Illness onset (high fever, cough, runny nose and red, watery eyes) begins a week or two after someone is exposed. A few days later, a rash breaks out as flat, red spots on the face and then spreads down the neck and trunk to the rest of the body. A person is contagious about four days before the rash appears to four days after.
Other measles symptoms may include small spots in the cheek area inside the mouth, diarrhea and ear infection. Measles can lead to pneumonia, swelling of the brain, deafness, intellectual disability and death.
Measles was officially declared eliminated from the United States in 2000, however, declining vaccination rates have led to multiple outbreaks in recent years. The country will lose its measles elimination status if endemic measles virus transmission continues in a defined geographic area for 12 months or more.
