L Pérez-Lago1, S Izco2, M Herranz1, G Tudó3, M Carcelén2, I Comas4, O Sierra2, J González-Martín3, M J Ruiz-Serrano1, J Eyene5, E Bouza6, D García de Viedma7. 1. Servicio de Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER Enfermedades respiratorias, CIBERES, Spain. 2. Servicio de Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain. 3. Servei de Microbiologia, Hospital Clinic-CDB, Barcelona, Spain; IS Global, Barcelona, Spain. 4. Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain; CIBER en Epidemiología y Salud Pública (CIBERESP), Spain. 5. Programa Nacional TB y Lepra, Malabo, Equatorial Guinea. 6. Servicio de Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER Enfermedades respiratorias, CIBERES, Spain; Departamento de Medicina, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain. 7. Servicio de Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBER Enfermedades respiratorias, CIBERES, Spain. Electronic address: dgviedma2@gmail.com.
Abstract
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.
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.