Latent Tuberculosis Infection

Alternate Terms:
  • Tuberculosis (Latent)
  • TB (Latent)
 Begin Learning with Healthy Advice:
Influenza (Flu), Pneumonia & Lower Respiratory Infection
Tuberculosis (TB)



Latent Tuberculosis Infection Definition by Healthwise:

Latent tuberculosis infection

A latent (inactive) tuberculosis (TB) infection is the presence of TB bacteria in a person's lungs even though he or she does 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 tuberculosis skin test.

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.

Author: Maria G. Essig, MS, ELS
Medical Review: Caroline S. Rhoads, MD - Internal Medicine
R. Steven Tharratt, MD, MPVM, FACP, FCCP - Pulmonology, Critical Care, Medical Toxicology
Last Updated: April 23, 2009

healthwise logo © 1995-2012 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

This information does not replace the advice of a doctor. Healthwise discalims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use.