Measles cases in the United States have surpassed 900, with infections confirmed in 24 states, according to newly released data from the Centers for Disease Control and Prevention.
At least 177 new cases were reported in the past week alone, bringing the national total to 910 confirmed infections so far this year.
Majority of Cases Among the Unvaccinated
CDC data shows that approximately 94% of measles cases involve individuals who are unvaccinated or whose vaccination status is unknown.
A small percentage of cases occurred among vaccinated individuals:
- 2% had received one dose of the MMR (measles, mumps, rubella) vaccine
- 3% had received the recommended two doses
Health officials note that one MMR dose is about 93% effective against measles, while two doses are approximately 97% effective.
Only six cases this year were linked to international visitors, indicating that most transmission is occurring domestically.
States Reporting Infections
Cases have been confirmed in 24 states, including:
Arizona, California, Colorado, Florida, Georgia, Idaho, Kentucky, Maine, Minnesota, Nebraska, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Utah, Vermont, Virginia, Washington and Wisconsin.
The majority of infections are occurring in individuals under age 19. About 3% of patients nationwide have required hospitalization, according to the CDC.
South Carolina and Florida Outbreaks Drive Surge
A significant outbreak in South Carolina — centered around Spartanburg County near the North Carolina border — has contributed to rising case numbers. As of this week, 933 cases have been confirmed there, with most infections linked to close contact with known patients.
In southern Florida, an outbreak at Ave Maria University has also led to dozens of confirmed cases, according to local health and campus officials.
Meanwhile, last month marked one year since a measles outbreak began in West Texas. Public health experts warn that if cases in other states are tied to that outbreak, the U.S. could risk losing its measles elimination status — a designation achieved after years of containment.
Vaccination Rates Decline
The CDC recommends two doses of the MMR vaccine — the first between 12 and 15 months of age and the second between 4 and 6 years old.
However, federal data shows vaccination rates have declined in recent years:
- 2019–2020 school year: 95.2% of kindergarteners vaccinated
- 2024–2025 school year: 92.5% vaccinated
Health experts warn that declining immunization rates leave communities vulnerable to outbreaks of preventable diseases like measles.
With cases continuing to rise, public health officials are urging families to ensure vaccinations are up to date to help prevent further spread.
For more health updates, stay tuned to Que Onda Magazine.