Dallas County Health and Human Services is investigating a possible tuberculosis exposure at MacArthur High School that occurred during the 2025-26 school year, according to health officials and Irving ISD.
The district strongly recommends that students returning to MacArthur as 10th-, 11th-, or 12th-graders this school year get tested for tuberculosis if they have not already been tested.
Incoming freshmen do not need to be tested, according to the district.
What We Know About the Possible Exposure
Dallas County Health and Human Services said the potential exposure occurred at MacArthur High School sometime during the previous school year. Officials have not disclosed when or where on campus the possible exposure occurred.
The agency said the risk to the general public remains low.
The testing recommendation is focused in part on identifying latent, or inactive, tuberculosis. People with latent TB infection generally do not have symptoms and cannot spread the bacteria to others, but the infection can become active tuberculosis in some cases if left untreated.
Irving ISD is offering tuberculosis testing to eligible students. Dallas County Health and Human Services or the Texas Department of State Health Services do not require the testing.
Officials have not released information about a potential source case, how many people may have been exposed, or whether any active tuberculosis cases have been identified in connection with the investigation.
Who Should Get Tested?
The district is recommending testing for students who:
- Attended MacArthur High School during the 2025-26 school year and are returning as 10th-, 11th-, or 12th-graders.
- Have not already been tested for tuberculosis.
Incoming ninth-grade students are not included in the testing recommendation.
Parents and students who have questions about testing can contact Irving ISD or MacArthur High School for additional information about available testing.
What Is Tuberculosis?
Tuberculosis is an infectious disease caused by bacteria that most commonly affects the lungs. Active tuberculosis can spread through the air when an infected person coughs, speaks, or sings.
Latent TB infection is different. A person can carry the bacteria without feeling sick or being contagious. Health officials may recommend testing after a potential exposure to determine whether someone has been infected.
Dallas County Health and Human Services said the overall risk remains low, but testing can help identify infections that may otherwise go undetected.
The investigation remains ongoing, and additional information about the possible exposure was not immediately available.
Provided by Dallas Express
