Molecular typing and antibiotic resistance of Shigella isolated from 2011 to 2014 in Shandong Province / 中华疾病控制杂志

ABSTRACT

Objective To study the characteristics and epidemic trend of Shigella in Shandong province through the analysis of serotype, virulence genes, molecular typing and drug sensitivity. Methods The serotype was classified using the method of slide agglutination. Polymerase chain reaction (PCR) was used to amplify the related virulence genes. The molecular typing was carried out by pulsed field gel electrophoresis (PFGE), and the antibiotic sensitivity of the strains was determined by micro-broth dilution method. Results The main serogroups of 44 Shigella strains were Shigella flexneri (54.55%) and Shigella sonnei (43.18%). The carrying rates of ipaH, Set1, Sen and ial were 100%, 43.18%, 56.82% and 50.00%, respectively. By PFGE typing, the strains of Shigella flexneri were divided into 18 patterns with a low similarity. The strains of Shigella sonnei were divided into 14 patterns, and the similarity of 89.47% of the strains was more than 90%. 44 strains of Shigella had different levels of resistance to 14 of the 15 antibiotics. 93.18% of the strains were multidrug resistant. Conclusion The Shigella in Shandong province is dominated by serogroups of Shigella flexneri and Shigella sonnei, with high virulence gene carrying rate, clustering distribution and severe antibiotic resistance. It is necessary to strengthen the monitoring on serotype, traceability and antibiotic resistance of Shigella in Shandong province.