Volume 101, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Two strains—M (sublineage 4.1) and Ra (sublineage 4.3)—have long prevailed in Argentina among patients with multidrug-resistant tuberculosis (MDR-TB). Recently, budget constraints have hampered the surveillance of MDR-TB transmission. Based on whole-genome sequence analysis, we used M- and Ra-specific single nucleotide polymorphisms to tailor two multiplex allele-specific polymerase chain reactions (PCRs), which we applied to 252 stored isolates (95% of all newly diagnosed MDR-TB cases countrywide, 2015–2017). Compared with the latest data available (2007–2009), the M strain has receded (80/324 to 20/252, < 0.0001), particularly among cross-border migrants (12/58 to 0/53, = 0.0003) and HIV-infected people (30/97 to 7/74, = 0.0007), but it still accounts for 4/12 new cases of extensively drug-resistant TB. Differently, the Ra strain remained stable in frequency (39/324 to 33/252) and contributed marginally to the extensive drug-resistance load (1/12). Our novel strategy disclosed recent trends of the two major MDR-TB strains, providing meaningful data to allocate control interventions more efficiently.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...


Data & Media loading...

  • Received : 24 May 2019
  • Accepted : 29 Jul 2019
  • Published online : 14 Oct 2019
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error