Skip to Main Content

Healthwise® Health Information

Health library

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. 0-9

Latent tuberculosis infection

Top of the page

Latent tuberculosis infection

A latent (inactive) tuberculosis (TB) infection is the presence of TB bacteria in a person's lungs even though they do not have symptoms of TB (such as coughing, weight loss, fatigue, or fever).

A person with latent tuberculosis infection has no signs of active TB on a chest X-ray, and no TB-causing bacteria can be found in the mucus from the person's lungs (sputum). The only proof that the person has a TB infection is a positive TB skin test or TB blood test (interferon-gamma release assay or IGRA).

People who have a latent TB infection do not spread the disease to other people. They may need to take medicine to prevent the bacteria from becoming active in the future.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

This information does not replace the advice of a doctor. Ignite Healthwise, LLC, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.

To learn more about Ignite Healthwise, LLC, visit webmdignite.com.

© 2024 Ignite Healthwise, LLC. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Ignite Healthwise, LLC.

This information does not replace the advice of a doctor. Ignite Healthwise, LLC, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.