Measles Outbreak in Texas Officially Ends
The Texas Department of State Health Services announced on Monday that a significant measles outbreak, which affected 762 individuals, has concluded. Officials noted that it has been over 42 days since a new case was recorded in any of the counties that previously showed evidence of ongoing transmission.
This outbreak contributed to the highest number of measles cases in the United States in more than three decades. As of August 5, the Centers for Disease Control and Prevention reported a total of 1,356 confirmed measles cases nationwide this year. To put that in perspective, there were only 285 cases in 2024.
The outbreak started in January within a rural Mennonite community known for low vaccination rates. Notably, more than two-thirds of the reported cases involved children, and unfortunately, two unvaccinated children succumbed to the virus; both had no known underlying health issues. During the outbreak, 99 individuals were hospitalized, which accounted for about 13 percent of all cases.
Measles is an extremely contagious respiratory illness that can temporarily weaken the immune system, making people susceptible to secondary infections like pneumonia. In some rare instances, it can result in brain swelling and long-lasting neurological damage. It can also lead to complications during pregnancy, such as premature births or low birth weight. The most effective prevention method is the measles, mumps, and rubella (MMR) vaccine, which is 93 percent effective after one dose and 97 percent effective after two doses.
An outbreak is deemed over after 42 days without new cases since this period is double the maximum incubation time for the virus, which is the longest duration between exposure and symptom development.
The CDC defines an outbreak as three or more linked cases, and this Texas outbreak has been associated with cases in neighboring states, as well as Mexico and Canada.
Even though the Texas outbreak has ended, measles cases continue to arise in other parts of the country. The CDC has indicated that 40 additional states have reported cases, with a total of 32 outbreaks in the US for 2025—compared to just 16 in 2024.
These ongoing outbreaks jeopardize the US measles elimination status, which indicates no domestic spread for over 12 months. This status was achieved in 2000 after a substantial increase in vaccination rates, but nearly slipped away in 2019 due to a significant outbreak in under-vaccinated Orthodox Jewish communities in New York.
As vaccination rates decline across the US, public health researchers are raising alarms about the potential for more outbreaks of measles and other diseases. One recent peer-reviewed study warned that, if current vaccination trends continue, measles could reestablish itself and become endemic in the country within the next twenty years.
