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Review
. 2016 Oct;79(4):201-206.
doi: 10.4046/trd.2016.79.4.201. Epub 2016 Oct 5.

Tuberculosis Infection and Latent Tuberculosis

Seung Heon Lee  1
Affiliations
Review

Tuberculosis Infection and Latent Tuberculosis

Seung Heon Lee. Tuberc Respir Dis (Seoul). 2016 Oct.

Abstract

Active tuberculosis (TB) has a greater burden of TB bacilli than latent TB and acts as an infection source for contacts. Latent tuberculosis infection (LTBI) is the state in which humans are infected with Mycobacterium tuberculosis without any clinical symptoms, radiological abnormality, or microbiological evidence. TB is transmissible by respiratory droplet nucleus of 1-5 µm in diameter, containing 1-10 TB bacilli. TB transmission is affected by the strength of the infectious source, infectiousness of TB bacilli, immunoresistance of the host, environmental stresses, and biosocial factors. Infection controls to reduce TB transmission consist of managerial activities, administrative control, engineering control, environmental control, and personal protective equipment provision. However, diagnosis and treatment for LTBI as a national TB control program is an important strategy on the precondition that active TB is not missed. Therefore, more concrete evidences for LTBI management based on clinical and public perspectives are needed.

Keywords: Infection; Infection Control; Latent Tuberculosis; Transmission; Tuberculosis.

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Conflict of interest statement

No potential conflict of interest relevant to this article was reported.

Figures

Figure 1
Figure 1. Schematic presentation of factors determining the likelihood of transmitting tuberculosis (TB) infection. BCG: bacillus Calmette–Guérin.
Figure 2
Figure 2. Schematic diagram for latent tuberculosis infection (LTBI) screening in tuberculosis (TB) contacts and noncontacts in Korea.
See this image and copyright information in PMC

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