A snapshot of genetic lineages of Mycobacterium tuberculosis in Ireland over a two-year period, 2010 and 2011

Irish Mycobacteria Reference Laboratory, St. James Hospital, Dublin, Ireland.
Eurosurveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin (Impact Factor: 5.72). 01/2013; 18(3).
Source: PubMed


Mycobacterial interspersed repetitive-unit-variable-number tandem repeat typing alone was used to investigate the genetic lineages among 361 Mycobacterium tuberculosis strains circulating in Ireland over a two-year period, 2010 and 2011. The majority of isolates, 63% (229/361), belonged to lineage 4 (Euro-American), while lineages 1 (Indo-Oceanic), 2 (East-Asian) and 3 (East-African–Indian) represented 12% of isolates each (42/361, 45/361, and 45/361, respectively). Sub-lineages Beijing (lineage 2), East-African–Indian (lineage 1) and Delhi/central-Asian (lineage 3) predominated among foreign-born cases, while a higher proportion of Euro-American lineages were identified among cases born in Ireland. Eighteen molecular clusters involving 63 tuberculosis (TB) cases were identified across four sub-lineages of lineage 4. While the mean cluster size was 3.5 TB cases, the largest cluster (involving 12 Irish-born cases) was identified in the Latin American–Mediterranean sub-lineage. Clustering of isolates was higher among Irish-born TB cases (47 of 63 clustered cases), whereas only one cluster (3/63) involved solely foreign-born individuals. Four multidrug-resistant cases identified during this period represented lineages 2 and 4. This study provides the first insight into the structure of the M. tuberculosis population in Ireland.

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Available from: Margaret Fitzgibbon, Jan 15, 2015
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    Eurosurveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin 02/2013; 18(4). · 5.72 Impact Factor
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