Surveillance and drug resistance analysis of non-typhoid Salmonella in Yuyao, Zhejiang, 2014–2018

ObjectiveTo understand the spread and drug resistance of non-typhoid Salmonella (NTS) in Yuyao, and provide scientific basis for clinical treatment and prevention of NTS infection.

MethodsThe samples of diarrhea patients collected from sentinel hospitals were tested for bacterial enrichment (using selenite brilliant green), isolation, identification, serotyping and drug susceptibility testing from 2014 to 2018.

ResultsA total of 299 NTS strains (12.85%) were detected from 2 327 samples of diarrhea patients, and 35 serotypes and 1 unspecified serotype were identified. The first four predominant serotypes were S. 4,5,12:i:-, S. typhimurium, S. Stanley and S. enteritidis. The detection rate of NTS was highest in summer (16.29%) and lowest in winter (2.33%). The infection cases in children aged ＜5 years accounted for 59.87% of the total. Drug susceptibility test showed that NTS had high resistance rates to penicillin and cephalosporin, low resistance rate to ciprofloxacin. And 111 strains were multidrug resistant. The resistance pattern of ACSSuT mainly existed in S.4,5,12:i:- and S. typhimurium strains.

ConclusionThe predominant serotypes of NTS were S.4,5,12:i:- and S. typhimurium in Yuyao. Children aged ＜5 years were susceptible to NTS infection, suggesting that it is necessary to strengthen the surveillance in children aged ＜5 years. The multidrug resistance of NTS was serious. It is necessary to have a rational use of antibiotics in clinical practice.