Tuberculosis (TB) Exposure at Meridian High School:  TB Testing Recommendations

December 4, 2024

Central District Health (CDH) has confirmed that exposure to TB may have occurred at Meridian High School in Meridian between August and November 2024. There is no ongoing risk, and people are safe to attend school and school events as usual.

CDH is working with Meridian High School and the West Ada School District to conduct a contact investigation to identify if any TB transmission might have occurred at the school. In the next few days, letters will be sent to all individuals who potentially had exposure and need TB testing.

Providers should be prepared to receive questions or requests for TB testing from people associated with Meridian High School. CDH recommends TB testing only be performed on staff or students who receive a letter indicating they were potentially exposed.

Testing

Testing for TB infection is conducted with a tuberculin skin test (TST, also called a PPD) or a blood test (IGRA, such as a T-SPOT). Please note:

• If a person has had a previous positive TST or IGRA they should not be tested again as the result will likely always be positive.
• If a person has received the BCG vaccine, a blood test is recommended, because a TST can have a false positive result.
• For a person exposed to someone with active TB disease, a TST is positive at 5 mm or greater induration.

Active TB cannot be diagnosed with these tests alone. People who have a positive test for TB infection must have a symptom review and chest x-ray. Common symptoms for active TB are chronic cough, fever, night sweats, and unexplained weight loss lasting three weeks or more. If you are concerned a patient might have active TB, call the Epidemiology Program at 208-327-8625.

CDH is also offering testing to people identified through this contact investigation if they do not have barriers to accessing medical care.

For questions or additional information go to https://www.cdc.gov/tb/testing/?CDC_AAref_Val=https://www.cdc.gov/tb/topic/testing/default.htm or call the Epidemiology Program at 208-327-8625.