Why Has the Management of Latent Tuberculosis Been Relegated in High Burden Countries? An Ounce of Prevention is Worth A Pound of Cure

Abstract

Latent tuberculosis infection (LTBI) is defined as the persistent immune response to stimulation by Mycobacterium tuberculosis antigens without evidence of clinically manifest active tuberculosis (TB). The lifetime risk of reactivation TB for an immunocompetent person with documented LTBI is estimated to be 5-15%. The most recent estimates of global latent tuberculosis infection (LTBI) is that approximately 1.7 billion people are infected worldwide, of which 10% are infected with an isoniazid-resistant strain. Prevention of new infections of Mycobacterium tuberculosis and their progression to active disease is critical to reduce the burden of disease and death caused by TB. Several high-risk groups, including individuals living with HIV and household contacts regardless of their age will benefit with treatment of LTBI. Unfortunately, according to the literature, globally, the proportion of LTBI subjects initiating treatment ranges from 24% to 98%, while the proportion of people completing LTBI treatment varies from 19% to 90%. Treatment of LTBI, as part of an integral approach to TB control, will facilitate the achievement of the targets of the WHO End TB strategy and eventually contribute to the elimination of TB.