A novel strategy based on genomics and specific PCR reveals how a multidrug resistant Mycobacterium tuberculosis strain became prevalent in Equatorial Guinea 15 years after its emergence

• Published in: Clinical microbiology and infection
• Main Authors: Pérez-Lago, Laura, Izco, Santiago, Herranz, Marta, Tudó i Vilanova, Griselda, Carcelén, María, Comas, Iñaki, Sierra, Olalla, González Martín, Julián, Ruiz-Serrano, María J, Eyene, Juan, Bouza Santiago, Emilio, García-de-Viedma, Darío
• Format: Journal Article
• Language: English
• Published: European Society of Clinical Microbiology and Infectious Diseases 13-10-2016
• Subjects: Equatorial Guinea; Genomics; Genòmica; Guinea Equatorial; Mycobacterium tuberculosis
• ISSN: 1198-743X

OBJECTIVE: Molecular epidemiology techniques in tuberculosis (TB) can identify high-risk strains that are actively transmitted. We aimed to implement a novel strategy to optimize the identification and control of multidrug-resistant (MDR) TB in a specific population. METHODS: We developed a strain-specific PCR tailored from whole genome sequencing (WGS) data to track a specific MDR prevalent strain in Equatorial Guinea (EG-MDR). RESULTS: The PCR was applied prospectively on remnants of GeneXpert reaction mixtures owing to the lack of culture facilities in Equatorial Guinea. In 147 (93%) of 158 cases, we were able to differentiate between infection by the EG-MDR strain or by any other strain and found that 44% of all rifampicin-resistant TB cases were infected by EG-MDR. We also analysed 93 isolates obtained from Equatorial Guinea 15 years ago, before MDR-TB had become the problem it is today. We found that two of the scarce historical MDR cases were infected by EG-MDR. WGS revealed low variability-six single nucleotide polymorphisms acquired by this strain over 15 years-likely because of the lack in the country of a specific program to treat MDR-TB. CONCLUSIONS: Our novel strategy, which integrated WGS analysis and strain-specific PCRs, represents a low-cost, rapid and transferable strategy that allowed a prospective efficient survey and fast historical analysis of MDR-TB in a population.