Tuberculosis (TB)

TB preventive care

A field worker interviews a woman holding her infant, writing notes in a book.
Vanessa Vick

One third of the world’s population is estimated to have latent TB infection (LTBI); in other words, they do not have active TB disease but may develop it through a process of reactivation of dormant bacilli that start multiplying and produce active TB. The lifetime risk of reactivation for a person with documented LTBI is estimated to be 5-10%, with the majority developing TB disease within 18 months of initial infection. However, the risk is considerably higher in the presence of predisposing factors, such as HIV infection. The management of LTBI is an innovative element of the “prevention package” of WHO’s End TB Strategy.

fact buffet


3 out of 10persons globally are thought to have latent TB infection

LTBI factsheet
pdf, 781kb


60-90%risk reduction of developing active TB with currently available treatment

Latent TB Infection: Updated and consolidated guidelines for programmatic management

Active TB

5-10%of people infected with TB bacteria have a lifetime risk of developing active TB disease.


Key topics

Latent TB infection (LTBI)

Latent tuberculosis infection (LTBI) is a state of persistent immune response to stimulation by Mycobacterium tuberculosis antigens without evidence of clinically manifested active TB. A direct measurement tool for M. tuberculosis infection in humans is currently unavailable. One-third of the world’s population is estimated to have LTBI: they do not have active TB disease but may develop it in the near or remote future, a process called “TB reactivation”.

Tuberculosis infection control

The potential impact of TB transmission in health-care and congregate settings on global TB morbidity and mortality has highlighted the urgent need to refocus attention on TB infection control. Lessons must be garnered from successful pilots and innovations, leading to models for national scale-up. This process requires the commitment of all implementing partners, coordination of stakeholder actions, and donor support.

Questions and answers on tuberculosis vaccines

The only existing vaccine against tuberculosis (TB), Bacille Calmette-Guérin (BCG), created in 1921, has variable protective efficacy. WHO recommends vaccinating HIV-uninfected infants with BCG as it provides protection against severe extrapulmonary (non-lung) forms of paediatric TB. However, BCG is unreliable in protecting against pulmonary TB, which accounts for most of the disease burden worldwide. A safe, effective and affordable TB vaccine would represent a major advance in the control of the disease.

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