LI Sheng, HE Jian, YANG Xiao-yan, XIN You-quan, JIN Juan, ZHANG Qi, BAI JI-xiang, YANG Han-qing, WU Hai-lian, DAI Rui-xia
Objective To determine the minimum inhibitory concentration (MIC) of 11 antibiotics against 46 strains of Yersinia pestis from the natural plague foci in Gansu province, China and master the sensitivity of these strains to the 11 antibiotics in this region, and to provide a scientific basis for the effective prevention and control of plague. Methods According to American Association of Clinical and Laboratory Standards (CLSI)(2017-M100), the agar dilution method was used to determine the MICs of ofloxacin, ciprofloxacin, sulfamethoxazole/trimethoprim, kanamycin sulfate, streptomycin sulfate, ceftriaxone sodium, ampicillin, chloramphenicol, spectinomycin hydrochloride, cefuroxime sodium, and tetracycline hydrochloride against 46 strains of Y. pestis. Results None of the 46 strains of Y. pestis tested were found to have resistance to one or more of the 11 antibiotics. Among the 11 antibiotics, ceftriaxone sodium had the highest in vitro antibacterial activity (MIC90, 0.03 μg/ml), followed by ciprofloxacin (MIC90, 0.06 μg/ml), sulfamethoxazole/trimethoprim (MIC90, 0.12 μg/ml), ofloxacin (MIC90, 0.25 μg/ml), ampicillin (MIC90, 0.50 μg/ml), cefuroxime sodium (MIC90, 1.00 μg/ml), kanamycin sulfate, streptomycin sulfate, tetracycline hydrochloride, and chloramphenicol (MIC90, 4.00 μg/ml), and spectinomycin hydrochloride had the lowest antibacterial activity (MIC90, 16.00 μg/ml). Conclusion The 46 strains of Y. pestis from the natural plague foci in Gansu province are all sensitive to the 11 antibiotics. Monitoring of drug-resistant strains should be continued in order to detect drug-resistant Y. pestis in the early stage, choose antibiotics rationally, and develop the individualized treatment regimen.
