Molecular Typing of Mycobacterium Tuberculosis Strains: A Fundamental Tool for Tuberculosis Control and Elimination

Abstract

Tuberculosis (TB) is still an important cause of morbidity and mortality worldwide. An improvement of the strategies for disease control is necessary in both low- and high-incidence TB countries. Clinicians, epidemiologists, laboratory specialists, and public health players should work together in order to achieve a significant reduction in TB transmission and spread of drug-resistant strains. Effective TB surveillance relies on early diagnosis of new cases, appropriate therapy, and accurate detection of outbreaks in the community, in order to implement proper TB control strategies. To achieve this goal, information from classical and molecular epidemiology, together with patient clinical data need to be combined. In this review, we summarize the methodologies currently used in molecular epidemiology, namely molecular typing. We will discuss their efficiency to phylogenetically characterize Mycobacterium tuberculosis isolates, and their ability to provide information that can be useful for disease control. We will also introduce next generation sequencing as the methodology that potentially could provide in a short time both, detection of new outbreaks and identification of resistance patterns. This could envision a potential of next generation sequencing as an important tool for accurate patient management and disease control.

Keywords: Tuberculosis; molecular typing; multidrug resistance; outbreak investigation; whole genome sequencing.

Figure 1.

The different methods used in molecular typing of Mycobacterium tuberculosis show different features in terms of technical challenges and resolution power of the genetic distances between the strains analyzed.

Figure 2.

A concerted use of classical and molecular epidemiology tools is required to control tuberculosis at local and regional level.