Detalle de: TB Transmission: Closing the Gaps

Molecular tools, including RFLP, spoligotyping, and MIRU-VNTR, have greatly enhanced our understanding of tuberculosis transmission [1, 2]. In settings where molecular tools are regularly employed, MIRU-VNTR is perhaps the most frequently used. The size of PCR amplicons spanning either 12, 15, or 24 repeat loci is used to infer a fingerprint for a given isolate, allowing surveillance programs to identify clusters of isolates potentially related by recent transmission. However, the increasing use of genomics in national TB surveillance programs is confirming what many in the TB community have long suspected – that MIRU-VNTR clusters often do not represent epidemiologically linked, recently transmitted cases, particularly for Mycobacterium tuberculosis isolates not belonging to Lineage 4.