Tuberculosis Testing

There are two tests for TB infection. The first is a blood test: interferon gamma release assay, for example QuantiFERON-TB Gold (QFT). Results are generally available within several days. The second method is the tuberculin skin test (TST) which requires a return visit for the reading in 48 to 72 hours. If either of these tests indicate TB infection, a chest x-ray is the next step for diagnosis.

Tuberculosis Prevention

To prevent TB, avoid contact with people who have active TB disease. Persons with active TB disease must be isolated and treated with specific antibiotics. Healthcare workers must follow TB control plans. Bacille Calmette-Guèrin vaccine (BCG) for tuberculosis is not used in the United States because it does not completely prevent TB. In countries where TB is common, BCG is often given to infants and children. History of BCG vaccine does not affect the blood test for TB but it may affect the tuberculosis skin test.

Tuberculosis Treatment

Latent tuberculosis infection can be treated by taking several months of antibiotics. During treatment, the health care provider monitors the patient’s health and response to the medications. Active tuberculosis disease is also treated with antibiotics, based on the culture and sensitivity of the bacteria. Often, more than one drug is needed. Isolation from other people is required for several weeks until the patient is no longer contagious. Throughout the contagious time, the person with tuberculosis disease must not attend class, jobs or social events. In both active and latent tuberculosis, it is very important to follow the medication schedules, complete all medications and stay in touch with the provider.

Additional Resources

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