Drug resistance and serotypes of 91 strains of Streptococcus pneumoniae

OBJECTIVE To investigate the antibiotics resistance and the prevalence of serotypes of Streptococcus pneumoniae isolated from the clinical patients in Chongqing.METHODS The capsular serotypes were identified by Quellung reaction and compared with the spectrum of the pneumococcal conjugate vaccine.Minimal inhibition concentrations(MICs) of the antibiotics were determined by the broth microdilution method.RESULTS The age profile of clinical patients infected by 91 strains of S.pneumoniae revealed a typical twin-peak distribution,with most patients being either 5 years old(51.7%) or ≥50 years old(27.5%).Among 91 clinical isolates,90 were divided into 20 serotypes and 1 was unable to serotype.The most prevalent serotypes of S.pneumoniae isolates were 19F,19A,6B,and PVC13 was expected to cover 74.4%.The majority of 91 isolates were resistant to common antibiotics.53.8% of 67 BLAs were penicillin non-susceptible S.pneumoniae.CONCLUSION The prevalent serotypes are 19F,19A,and 6B in Chongqing,and PVC13 is an effective vaccine to prevent the S.pneumoniae infections.The antibiotics resistance of S.pneumoniae strains is very serious,the majority of the isolates are multidrug-resistant,thus it is necessary to focus on the clinical reasonable use of antibiotics.