Update on the Measles Outbreak

The country’s measles outbreak has surpassed 1,000 cases for the first time in 30 years, the Centers for Disease Control and Prevention revealed as of May 10, 2025.

The data, which is based on confirmed measles cases reported to CDC, show that the disease has now hit 1,001 people in a total of 31 states, a sharp uptick from the 285 reported cases in all of 2024.

In 2025 alone, there have been a total of 14 outbreaks, which is categorized as three or more related cases—93% of the 1,001 cases were from these outbreaks. As of May 11, 2025, the ongoing measles outbreak in the United States has resulted in three confirmed deaths. These fatalities include two unvaccinated children in Texas and one unvaccinated adult in New Mexico. This marks the first time since 2015 that measles-related deaths have been reported in the US.

Key Highlights

Epicenter in Texas: Texas accounts for the majority of cases, with 709 reported infections. The outbreak is concentrated in a Mennonite community and has spread to neighboring states, including New Mexico, Oklahoma, and Kansas.

Vaccination Status: Approximately 96% of the 1,001 cases involved individuals who were unvaccinated or had unknown vaccination status. Children under age 5 represent one-third of the cases.

Declining Vaccination Rates: National MMR vaccination rates among US kindergartners have declined from 95.2% in the 2019-2020 school year to 92.7% in 2023-2024, undermining herd immunity.

Hospitalizations: Approximately 13% of those infected have required hospitalization.

The Centers for Disease Control and Prevention (CDC) has issued a Health Alert Network advisory, emphasizing the importance of MMR vaccination, especially before international travel. The CDC continues to work closely with state and local health departments to monitor and contain the outbreak.