title: Finer characterization of Mycobacterium tuberculosis using spoligotyping and 15-loci MIRU-VNTRs reveals phylogeographical specificities of isolates circulating in Guyana and Suriname.
abstract: In this study we used spoligotyping and 15-loci MIRU-VNTRs for a finer characterization of Mycobacterium tuberculosis strains isolated from patients residing in Guyana (n=74) and Suriname (n=80). The mean age of the patients was 38.5years (36.5 and 40.2years for Guyana vs. Suriname), with a male-to-female sex-ratio of 2.25 for Guyana vs. 4.27 in Suriname. Spoligotyping and 15-loci MIRU-VNTRs led to a total of 41 and 65 different patterns respectively, with an overall clustering rate of 83.8% vs. 68.8%. Combined spoligotyping and VNTR analysis led to the detection of 18 clusters of 2-41 isolates, with an overall clustering of 67.5% and a recent "n-1" transmission rate of 55.8%. Importantly, Guyana was characterized by a significantly higher percentage of clustered isolates than Suriname (79.7% vs. 56.3%; p=0.0019). Three big spoligo/MIRU (SIT/MIT) clusters containing >10 isolates each were shared between the 2 countries, and concerned: T1 sublineage cluster 53/861 (n=41, 37 in Guyana vs. 4 in Suriname); EAI6-BGD1 sublineage cluster 1340/860 (n=16, 3 in Guyana vs. 13 in Suriname); and T1 sublineage cluster 131/146 (n=11, 6 in Guyana vs. 5 in Suriname); as well as 2 smaller clusters of 2 and 3 isolates respectively. However, the relative phylogeographical specificities of strains in circulation as well as a lack of drug-resistance observed among strains from Suriname suggested that trans-border transmission of drug-resistant isolates occurred less frequently than thought. Tracing and interrupting transmission channels of a specific clone (SIT53/15-MIT861) should become a priority in Guyana, not only because it is by far most abundant but also because it accounts for almost half of the drug resistant isolates (n=8/17, 47.1%) in our study, and clustered 5/12 (41.7%) MDR isolates.
authors.affiliation: WHO Supranational TB Reference Laboratory, Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de Guadeloupe, Abymes Cedex, Guadeloupe.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Streit
authors.affiliation: Department of Para-Clinical Sciences, Faculty of Medical Sciences, The University of the West Indies, St. Augustine, Trinidad and Tobago.
authors.forename: Shirematee
authors.initials: S
authors.lastname: Baboolal
authors.affiliation: Department of Para-Clinical Sciences, Faculty of Medical Sciences, The University of the West Indies, St. Augustine, Trinidad and Tobago.
authors.forename: Patrick E
authors.initials: PE
authors.lastname: Akpaka
authors.affiliation: WHO Supranational TB Reference Laboratory, Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de Guadeloupe, Abymes Cedex, Guadeloupe.
authors.forename: Julie
authors.initials: J
authors.lastname: Millet
authors.affiliation: WHO Supranational TB Reference Laboratory, Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de Guadeloupe, Abymes Cedex, Guadeloupe. Electronic address: nrastogi@pasteur-guadeloupe.fr.
authors.forename: Nalin
authors.initials: N
authors.lastname: Rastogi
mesh_terms: D016000:Cluster Analysis; D005260:Female; D006172:Guyana / Q000453:epidemiology; D006801:Humans; D020071:Interspersed Repetitive Sequences / Q000235:genetics*; D008297:Male; D018598:Minisatellite Repeats / Q000235:genetics*; D058889:Molecular Typing; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics*; D058974:Phylogeography; D013532:Suriname / Q000453:epidemiology; D014376:Tuberculosis / Q000453:epidemiology / Q000382:microbiology*
keywords: Guyana; MIRU-VNTRs; Mycobacterium tuberculosis; Population structure; Spoligotyping; Suriname