Infection and Drug Resistance (Dec 2022)
Genetic Diversity, Antibiotic Resistance, and Virulence Gene Features of Methicillin-Resistant Staphylococcus aureus Epidemics in Guiyang, Southwest China
Abstract
SuWen Yang,1– 3,* Bing Wang,2,4,5,* Jing Li,6 Xue Zhao,7 Yan Zhu,8 Qian Sun,9 HongMei Liu,2,4,5 XiaoJun Wen1 1School of Basic Medical Sciences, Basic Medical School, Guizhou Medical University, Guiyang, 550025, People’s Republic of China; 2Engineering Research Centre of Medical Biotechnology, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 3People’s Hospital of Kaiyang, Guiyang, 550300, People’s Republic of China; 4Key Laboratory of Biology and Medical Engineering, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 5School of Biology and Engineering, Guizhou Medical University, Guiyang, Guizhou, 550025, People’s Republic of China; 6Department of Microbial Immunology, The First Affiliated Hospital of Guizhou Medical University, Guiyang, 550004, People’s Republic of China; 7Department of Clinical Laboratory, The First People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China; 8Department of Clinical Laboratory, The Fourth People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China; 9Department of Emergency Medicine, The First People’s Hospital of Guiyang, Guiyang, 550002, People’s Republic of China*These authors contributed equally to this workCorrespondence: XiaoJun Wen; HongMei Liu, Guizhou Medical University, Guiyang, 550025, People’s Republic of China, Email [email protected]; [email protected]: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common pathogens of community- and hospital-acquired infections, and its prevalence is increasing globally. Guiyang is the capital city of Guizhou Province, Southwest China; as the transport and tourism centre of Southwest China, Guizhou Province is bordered by Yunnan, Sichuan, Chongqing, and Guangxi Provinces. Although MRSA prevalence is increasing, little is known about its aspects in the area. The purpose of this study was to analyse MRSA molecular characteristics, antimicrobial resistance, and virulence genes in Guiyang.Methods: In total, 209 MRSA isolates from four hospitals (2019– 2020) were collected and analysed by antimicrobial susceptibility testing and molecular classification by the MLST, spa, and SCCmec typing methods. Isolate antibiotic resistance rates were detected by a drug susceptibility assays. PCR amplification was used to detect the virulence gene-carrying status.Results: Twenty-four STs, including 4 new STs (ST7346, ST7347, ST7348, and ST7247) and 3 new allelic mutations, were identified based on MLST. The major prevalent ST type and clone complex were ST59 (49.8%) and CC59 (62.7%), respectively. Spa type t437 (42.1%) and SCCmec IV (55.5%) were identified by spa and SCCmec typing methods as the most important types. Drug sensitivity data showed that the multidrug resistance rate was 79.0%. There were significant differences in multidrug resistance rates and virulence gene-carrying rates for seb, hla, hlb, cna and bap between ST59 and non-ST59 types.Conclusion: ST59-SCCmecIV-t437 is a major epidemic clone in Guiyang that should be monitored by local medical and health institutions. The situation differs from other adjacent or middle provinces of China, which may be due to the special geographical location of the region and the trend in antibiotic use or lifestyle. This study provides empirical evidence for local medical and health departments to prevent and control the spread of MRSA.Keywords: methicillin-resistant Staphylococcus aureus, MRSA, multilocus sequence type, MLST, Staphylococcal protein A type, SPA, Staphylococcal chromosomal cassette mec type, SCCmec, multidrug-resistant organism, virulence gene
