Characterization of Group B Streptococcus Recovered from Pregnant Women and Newborns Attending in a Hospital in Beijing, China

Xiaoou Li; Wei Gao; Zhonglan Jia; Kaihu Yao; Jinyan Yang; Jingjing Tong; Yajuan Wang

doi:10.2147/IDR.S395942

Characterization of Group B Streptococcus Recovered from Pregnant Women and Newborns Attending in a Hospital in Beijing, China

Infect Drug Resist. 2023 Apr 27:16:2549-2559. doi: 10.2147/IDR.S395942. eCollection 2023.

Authors

Xiaoou Li¹, Wei Gao², Zhonglan Jia³, Kaihu Yao², Jinyan Yang¹, Jingjing Tong⁴, Yajuan Wang⁵

Affiliations

¹ Department of Neonatology, Haidian District Maternal and Child Health Care Hospital, Beijing, 100080, People's Republic of China.
² Key Laboratory of Major Diseases in Children, Ministry of Education, National Key Discipline of Pediatrics (Capital Medical University), Laboratory of Dermatology, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, People's Republic of China.
³ Department of Clinical Laboratory, Haidian District Maternal and Child Health Care Hospital, Beijing, 100080, People's Republic of China.
⁴ Department of Neonatology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, 100026, People's Republic of China.
⁵ Department of Neonatology, Children's Hospital, Capital Institute of Pediatrics, Beijing, 100020, People's Republic of China.

Abstract

Purpose: We investigate the drug resistance, serotype and multilocus sequence typing (MLST) of Group B streptococcus (GBS) strains obtained from pregnant women and neonates in a hospital in Beijing.

Patients and methods: In this cross-sectional study, 1470 eligible pregnant women at a gestational age of 35-37 weeks presented to our department between May 2015 and May 2016 were included. Vaginal and rectal samples from pregnant women together with sampling from neonatal samples were collected to screen GBS. GBS strains were subject to drug resistance and serotype analysis and MLST.

Results: GBS strains were isolated from 111 pregnant women (7.6%) and 6 neonates (0.99%) from 606 matched neonates. 102 strains from pregnant women and 3 strains from neonates were included in the drug sensitivity test, serotyping and MLST typing. All these strains were susceptible to ampicillin, penicillin, ceftriaxone, vancomycin, linezolid, and meropenem. Sixty strains (58.8%) showed multi-drug resistance. Serious cross-resistance was seen between erythromycin and clindamycin. There were eight serotypes, and 37 strains (36.3%) showed a serotype of type III serving as the major type. All 102 GBS strains isolated from pregnant samples could be divided into 18 STs types. They belonged to five clonal complexes and five single clones, with the predominant type of ST19/III, ST10/Ib, and ST23/Ia, with CC19 as the most common type. Three GBS strains isolated from neonates covered two serotypes (ie type III and Ia) that were consistent with those of the mothers.

Conclusion: Serotype III was the predominant serotype of GBS in this study. The predominant MLST type was ST19, ST10, and ST23, with ST19/III, ST10/Ib, and ST23/Ia serving as the most prevalent and CC19 as the most common clonal complex. GBS strains from neonates were consistent in the clonal complex, serotype, and MLST with these isolated from the mothers.

Keywords: Group B streptococcus; drug resistance; molecular epidemiology; multilocus sequence typing.

Grants and funding

This study was supported by Special Fund of the Pediatric Medical Coordinated Development Center of Beijing Municipal Administration of Hospitals (XTYB201806).