Article ID: JJID.2020.592
The Vibrio species undergo cryptic changes in their genetic material for better adaptability, which accounts for antibiotic resistance. In the present study, we investigated the emergence and spread of sensitivity to polymyxin B by V. cholerae O1 El Tor strains from 1995 to 2019 in Odisha, India. The results exhibited that out of 1200 V. cholerae O1 strains, 89.4% were resistant and remaining 10.6% strains were sensitive to polymyxin B. The sensitivity to polymyxin B by V. cholerae O1 strains emerged from 2005 to 2019 except 2015 that clearly signifies the presence of classical biotype characteristics possessed by El Tor variant V. cholerae O1 strains. The Etest assay revealed some interesting trait of polymyxin B susceptibility on ctxB1 and ctxB7 genotypes of V. cholerae O1 strains. The minimum inhibitory concentration (MIC) of ctxB7 genotypes showed reduced MIC values of ≤ 4µg/ml; whereas ctxB1 genotypes exhibited higher MIC values of 24 and 32µg/ml.
