TABLE 1

MICs of different antimicrobial agents for selected Borrelia burgdorferisensu lato and relapsing-fever Borrelia strainsa

Antimicrobial and methodMIC rangeb (mg/liter)
B. burgdorferi sensu latoRelapsing-fever Borrelia strain
PKoB31HT31LB-2001HS1
Amoxicillin
    Microscopy41–23216–3216–32
    MIC120.5888
    MIC2221688
Doxycycline
    Microscopy220.50.125–0.250.5
    MIC110.1250.250.06250.25
    MIC210.50.50.1250.25
Ceftriaxone
    Microscopy0.1250.06–0.1250.0625–0.250.25–0.50.25–0.5
    MIC10.06250.031250.031250.031250.125
    MIC20.06250.031250.06250.1250.125
Azithromycin
    Microscopy0.01280.01280.003–0.0060.0030.0128
    MIC10.01280.0030.0030.0030.0128
    MIC20.01280.02560.0030.0030.006
Amikacin
    Microscopy2565126451232–64
    MIC15125123251264
    MIC2256512641,02464
  • a PKo, B. afzelii reference strain; B31, B. burgdorferi sensustricto reference strain; HT31, B. miyamotoi tick isolate (Japan); LB-2001, B. miyamotoi tick isolate (United States); HS1, B. hermsii reference strain.

  • b Ranges are results of tests that were conducted in quadruplicate.