Penetration of the fluoroquinolones in tuberculosis lesions is heterogeneous even in fully cellular areas, is driven by macrophage content and decreases as the distance from lesion outer rim increases.
A fluoroquinolone resistant variant of Salmonella Typhi has emerged that is likely to be widespread in the Indian subcontinent; therefore fluoroquinolones should not be recommended for empirical typhoid fever therapy in this setting.
The major evolutionary routes to drug resistance in Salmonella Typhi are associated with fitness benefits, not fitness costs, implying that prudent antimicrobial use will have no effect as a public health intervention in controlling typhoid fever.
Mutations in several components of a bacterial ribosome are shown to broadly decrease antibiotic and stress sensitivity, and readily accessible reversion mutations allow these ribosomal mutations to serve as stepping stones to high level antibiotic resistance.
Interventions in feedlots and abattoirs place selective pressure on the beef cattle resistome, which differentially impacts the public health risk of antimicrobial resistance from beef production sources.
HIV co-infection does not affect Mycobacterium tuberculosis mutation rates and does not drive the emergence of antimicrobial resistance within patients in the largest outbreak of multidrug-resistant tuberculosis in Latin America to date.
The genetic make-up of dominating MDR-TB clades in Central Asia is shaped by programmatic and socio-economic changes that led to fixation of resistance and bacterial fitness related mutations in the Soviet era.