Identification of lineages and sublineages of the Mycobacterium tuberculosis complex using advanced molecular strategies and WGS in Seville, Spain (2015–2022)

Abstract

Introduction

Tuberculosis (TB) in the Virgen del Rocío university hospital health area, included in the Seville Health District, Spain, exceeds the rate of 17 cases/100,000 inhabitants. Within the Mycobacterium tuberculosis complex (MTBC), M. tuberculosis sensu stricto comprises seven phylogenetic lineages (L1–L4 and L7–L9). The objective of this work is to know the circulating lineages in the area.

Methods

Molecular typing and sequencing were performed to identify circulating lineages from 2015 to 2022.

Results

From 2015 to 2019, the following were identified: L4 (95.95%, n = 355), L2 (1.62%, n = 6), and L6 (1.08%, n = 4). From 2020 to 2022: L4 94.62% (n = 123); L1 1.5% (n = 2); L3 1.5% (n = 2) and L2 0.76% (n = 1).

Conclusions

The emergence of different lineages in our area and their recognition are key to contributing to disease control. These findings demonstrate the need to continue surveillance and apply sequencing to understand and control the dynamics of TB transmission.

Resumen

Introducción

La tuberculosis (TB) en el área sanitaria hospital universitario Virgen del Rocío, incluido en el Distrito sanitario Sevilla, España, supera la tasa de 17 casos/100.000 habitantes. Dentro del complejo Mycobacterium tuberculosis (MTBC), M. tuberculosis sensu stricto comprende siete linajes filogenéticos (L1–L4 y L7–L9). El objetivo de este trabajo es conocer los linajes circulantes del área.

Métodos

Se realizó tipificación molecular y secuenciación para identificar los linajes circulantes de 2015 a 2022.

Resultados

De 2015 a 2019 se identificaron: L4 (95,95%, n = 355), L2 (1,62%, n = 6) y L6 (1,08%, n = 4). De 2020 to 2022: L4 94.62% (n = 123); L1 1,5% (n = 2); L3 1,5% (n = 2) y L2 0,76% (n = 1).

Conclusiones

La aparición de linajes diferentes en nuestra área y reconocerlos es clave para contribuir al control de la enfermedad. Estos hallazgos evidencian la necesidad de continuar con la vigilancia y aplicar la secuenciación para controlar la dinámica de la transmisión de TB.