ABSTRACT
OBJECTIVES: Compare the molecular epidemiology of tuberculosis (TB) between two large Canadian provinces-Ontario and British Columbia (BC)-to identify genotypic clusters within and across both provinces, allowing for an improved understanding of genotype data and providing context to more accurately identify clusters representing local transmission. DESIGN: We compared 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) genotyping for 3,314 Ontario and 1,602 BC clinical Mycobacterium tuberculosis isolates collected from 2008 through 2014. Laboratory data for each isolate was linked to case-level records to obtain clinical and demographic data. RESULTS: The demographic characteristics of persons with TB varied between provinces, most notably in the proportion of persons born outside Canada, which was reflected in the large number of unique genotypes (n = 3,461). The proportion of clustered isolates was significantly higher in BC. Substantial clustering amongst non-Lineage 4 TB strains was observed within and across the provinces. Only two large clusters (≥10 cases/cluster) representing within province transmission had interprovincial genotype matches. CONCLUSION: We recommend expanding analysis of shared genotypes to include neighbouring jurisdictions, and implementing whole genome sequencing to improve identification of TB transmission, recognize outbreaks, and monitor changing trends in TB epidemiology.
Subject(s)
Mycobacterium tuberculosis/genetics , Tuberculosis/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Typing Techniques , British Columbia/epidemiology , Child , Child, Preschool , Female , Genotyping Techniques , Humans , Infant , Infant, Newborn , Male , Middle Aged , Molecular Epidemiology , Ontario/epidemiology , Tuberculosis/transmission , Whole Genome Sequencing , Young AdultABSTRACT
A collection of 1,308 clinical Mycobacterium tuberculosis isolates from Ontario, Canada, was genotyped by IS6110 restriction fragment length polymorphism (RFLP) and mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. RFLP or >12 MIRU-VNTR loci were necessary for resolution of Indo-Oceanic strains. The low clustering rate and high strain diversity indicate that, in Ontario, most tuberculosis results from reactivation of latent infections.
Subject(s)
Bacterial Typing Techniques/methods , DNA Fingerprinting/methods , DNA, Bacterial/genetics , Minisatellite Repeats , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/isolation & purification , Polymorphism, Restriction Fragment Length , Tuberculosis/epidemiology , Cluster Analysis , DNA Transposable Elements , Genotype , Humans , Molecular Epidemiology , Mycobacterium tuberculosis/genetics , Ontario/epidemiology , Polymorphism, GeneticABSTRACT
The Seeplex TB Detection-2 assay (Rockville, MD) is a nested endpoint PCR for the Mycobacterium tuberculosis complex (MTBC) targets IS6110 and MPB64 that utilizes dual priming oligonucleotide technology. When used to detect the presence of MTBC DNA in formalin-fixed paraffin-embedded tissue specimens, the sensitivity and specificity of this assay is equivalent to a labor-intensive traditional endpoint PCR assay and is more sensitive than a commercial real-time PCR assay.
