What should you know about a gamma TB test?

A positive result may indicate TB infection, including infection without current symptoms. It does not alone distinguish inactive infection from active disease. A negative result makes infection less likely, but timing, immune health, recent exposure, and the quality of the sample can affect interpretation. If active tuberculosis is suspected, symptoms, examination, chest imaging, and sometimes sputum testing help complete the assessment.

Have the blood sample taken at the arranged laboratory and tell the clinician about previous TB tests, vaccination history, exposure, travel, immune-suppressing medicines, and symptoms. Do not treat a positive result as proof that you are contagious. The clinician may recommend [Chest X-Ray](/treatments/diagnostics-and-screening/chest-x-ray/) or another assessment. Read more about [Tuberculosis Screening](/treatments/diagnostics-and-screening/tuberculosis-screening/) and ask how results affect your care.

Seek prompt medical assessment for a cough lasting several weeks, coughing blood, fever, night sweats, unexplained weight loss, chest pain, or worsening breathlessness. Seek emergency help for severe breathing difficulty, confusion, or coughing up a large amount of blood. Do not wait for a screening result if you feel seriously unwell.

Ask whether your result is positive, negative, or indeterminate; whether a repeat sample is needed; and whether you need imaging or treatment. Ask what symptoms should prompt urgent review and whether close contacts require assessment. You can also ask how the result will be recorded for occupational or travel paperwork.