Skip to content

The Difference Between Latent TB Infection and Active TB Disease

Home » Health Information » Infectious Diseases » Tuberculosis » The Difference Between Latent TB Infection and Active TB Disease

A Person With Latent Tuberculosis (TB) Infection

  • Does not feel sick
  • Has no symptoms
  • Cannot spread TB to others
  • Usually has a positive skin test or IGRA blood test
  • Has a normal chest x-ray and sputum test

A Person With Active Tuberculosis (TB) Disease

  • Feels sick
  • Has symptoms that may include:
    • A bad cough that lasts 3 weeks or longer
    • Pain in the chest
    • Coughing up blood or sputum
    • Weakness or fatigue
    • Weight loss
    • No appetite
    • Chills
    • Fever
    • Sweating at night
  • May spread TB to others
  • Usually has a positive skin test or IGRA blood test
  • May have an abnormal chest x-ray and/or positive sputum smear or culture

Reference

Centers for Disease Control and Prevention. “The Difference Between Latent TB Infection and TB Disease”. November 2011.