ABSTRACT
Objective To analyze the serotypes and antimicrobial susceptibility profile of Group B Streptococcus (GBS) in perinatal pregnant women.Methods The vaginal and rectal specimens were collected from pregnant women at 35 to 37 weeks of pregnancy for culture and identification.The serotypes were analyzed using agglutination assay.Antimicrobial susceptibility testing was conducted by using Kirby-Bauer method,and interpreted according to 2009 CLSI breakpoints.The data were analyzed via WHONET 5.6 software.Results The prevalence of GBS was 10.4％ (264/2 533) in the 2 533 perinatal pregnant women.Serotype Ⅲ,Ⅰa and Ⅰb was identified in 54.9％ (84/153),17.6％ (27/153) and 13.1％ (20/153) of the GBS,respectively.All the GBS isolates were susceptible to penicillin,cefiriaxone and vancomycin.But 32.9％,68.1％ and 62.1％ of the isolates were resistant to levofloxacin,erythromycin and clindamycin,respectively.The antibiotic resistance rate of serotype Ⅲ isolates to the above three antibiotics was significantly higher than the other serotypes.Conclusions GBS may colonize both vagina and rectum of pregnant women.Vaginal and rectal secretions should be sampled simultaneously for better screening GBS.GBS serotype Ⅲ was the predominant serotype.Penicillin can be used as the first-choice treatment for GBS infections in pregnant women and newborns.GBS-positive pregnant women should be given the intervention treatment immediately to ensure the health of perinatal infants.