TABLE 4

Fraction of drug resistance acquired through person-to-person transmission versus de novo evolution of resistance within individual patients for each druga

DrugNo. of acquisitionsEstimated % de novoEstimated % transmission
First-line drugs
    Isoniazid71090
    Rifampin91387
    Ethambutol152278
    Pyrazinamide94753
Second-line drugs
    Amikacin102674
    Ethionamide93961
    Ofloxacin275446
Other drugs
    Streptomycin101387
  • a Parsimony was used to estimate the number of times genotypic resistance was gained in isolates with AST results. This number was divided by the total number of phenotypically resistant isolates to estimate the fraction of resistance to each drug acquired through de novo evolution, while the remaining fraction was assigned to acquisition from person-to-person transmission.