The Dallas County Health and Human Services Department and the Texas Department of State Health Services are investigating possible tuberculosis exposure at MacArthur High School in Irving. Health officials recommended tuberculosis testing for students who attended MacArthur High School during th e 2025–2026 school year and are returning as 10th-, 11th-, or 12th-graders, out of an abundance of caution. Officials said the testing recommendation does not apply to incoming 9th-graders, new students, or students who were already tested during the 2025–2026 school year. Testing is recommended because inactive, or latent, tuberculosis often causes no symptoms, officials said. According to officials, the risk to the public remains low, and the recommendation does not mean students were exposed to or have tuberculosis. What is Tuberculosis (TB)? Tuberculosis is caused by a bacterium and typically affects the lungs but can also infect the brain, kidneys and spine, according to the Centers for Disease and Prevention. TB can affect multiple parts of the body at the same time. Not everyone infected with TB germs becomes sick, but those who do get sick must seek medical care. If not treated properly, TB can be fatal. What are the symptoms of TB? Symptoms of TB include a cough lasting three weeks or more, chest pain, coughing up blood or sputum, weakness or fatigue, weight loss, loss of appetite, chills, fever and night sweats. How does TB spread? TB spreads through the air from one person to another when an infected person with active TB speaks, coughs, or sings. Germs can remain airborne for several hours and are more likely to spread indoors and in poorly ventilated areas. TB facts The CDC estimates that as many as 13 million people in the US live with inactive TB, and that 1 in 10 of those people will get sick with active TB. Without treatment, TB can be fatal. There were 9,633 reported cases of TB in the US in 2023. World Health Organization Mar 9, 2025 World Health Organization warns of possible tuberculosis surge because of USAID cuts World Health Organization Oct 30, 2024 Tuberculosis infected 8 million people last year, the most WHO has ever tracked Colleges Universities May 20, 2024 Girl, 16, who battled tuberculosis, becomes youngest graduate at Texas Woman's University This story uses functionality that may not work in our app. Click here to open the story in your web browser. ...read more read less