title: Strain diversity of mycobacteria isolated from pulmonary tuberculosis patients at Debre Birhan Hospital, Ethiopia.
abstract: BACKGROUND
  Ethiopia ranks seventh in the list of 22 high tuberculosis (TB) burden countries, with an incidence rate of 379 cases per 100,000 population for TB all forms. However, information on the genomic diversity of Mycobacterium tuberculosis in Ethiopia is limited.
  
  
  OBJECTIVE
  To investigate the molecular characteristics of M. tuberculosis strains implicated in pulmonary TB in the study area.
  
  
  RESULTS
  A cross-sectional study was conducted using socio-demographic, clinical and culture data combined with molecular typing analysis. The proportion of TB and M. tuberculosis isolates was not associated with risk factors (P > 0.05). Of 99 sputum samples, 80.8% were culture-positive. Speciation of isolates showed that 88.8% were M. tuberculosis. Further characterisation led to the identification of 27 different spoligotype patterns of M. tuberculosis; the most dominant shared types were SIT149, SIT53 and SIT54. Of the 27 strains, three strains were new and were reported to the SITVIT database. More than two thirds of the strains belonged to the Euro-American lineage.
  
  
  CONCLUSIONS
  This study shows the presence of several clusters and new strains of M. tuberculosis circulating in pulmonary TB patients in the study area, suggesting recent transmission. Nationwide studies are recommended to map the population structure of M. tuberculosis and set control measures.
authors.affiliation: Faculty of Veterinary Medicine, University of Gondar, Gondar, Ethiopia. legesse_lg@yahoo.com
authors.forename: L
authors.initials: L
authors.lastname: Garedew
authors.forename: A
authors.initials: A
authors.lastname: Mihret
authors.forename: G
authors.initials: G
authors.lastname: Mamo
authors.forename: T
authors.initials: T
authors.lastname: Abebe
authors.forename: R
authors.initials: R
authors.lastname: Firdessa
authors.forename: Y
authors.initials: Y
authors.lastname: Bekele
authors.forename: G
authors.initials: G
authors.lastname: Ameni
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003430:Cross-Sectional Studies; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D016680:Genome, Bacterial; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification*; D012307:Risk Factors; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology / Q000382:microbiology*; D055815:Young Adult