What should you know about annual TB testing?

A clinician or occupational-health service may recommend repeat testing after new contact with infectious tuberculosis, continued work in a setting with exposure, or another change that increases risk. A calendar alone does not determine whether testing is useful.

A TB blood test or skin test looks for an immune response suggesting infection with tuberculosis bacteria. A positive screening result does not by itself show whether infection is inactive or causing active disease, and it does not identify how recently exposure occurred.

Further assessment may include a symptom review, medical examination, chest X-ray and sometimes sputum testing. Previous BCG vaccination, earlier test results and medicines that suppress immunity help the clinician choose and interpret the test.

Bring records of earlier skin or blood tests, any prior positive result, chest imaging, BCG vaccination and treatment for TB infection or disease. Explain recent close contact, travel or residence in places where exposure occurred, healthcare or congregate-setting work, and any condition or medicine that weakens immune defences.

If a skin test is used, confirm when you must return so the reaction can be read within the required window. Do not repeat a skin test on your own interpretation; swelling must be measured correctly by trained staff. Follow-up matters more than the screening result alone.

Arrange medical assessment if you have a persistent cough, cough up blood, develop unexplained fever or night sweats, lose weight without trying, or have ongoing fatigue, especially after known TB exposure. Symptoms require diagnostic evaluation rather than waiting for the next annual screen.

Contact a healthcare service promptly after close exposure to someone with infectious TB, even if you feel well. The timing and type of testing may depend on when contact occurred, and a clinician may plan a later repeat test if the first assessment was soon after exposure.

Ask what specific exposure or policy makes repeat testing appropriate, whether a blood or skin test suits you, and how a previous BCG vaccination affects the choice. If your result is positive, ask which checks will distinguish inactive infection from active TB and whether treatment is recommended.