Trends in molecular characteristics and antimicrobial resistance of group B streptococci: a multicenter study in Serbia, 2015–2020

Abstract

Group B Streptococcus (GBS) is a major cause of neonatal morbidity and mortality. Serbia has not fully implemented preventive measures against GBS neonatal diseases. Therefore, we aimed to assess the maternal GBS colonisation and invasive neonatal disease rate, to reveal the trends of antimicrobial resistance and serotype distribution of GBS from various patient groups. Randomly selected non-invasive (n = 991) and all invasive GBS (n = 80) collected throughout Serbia from 2015 to 2020 were tested for antimicrobial susceptibility, capsular typing, and hvgA detection. Overall, 877/5621 (15.6%) pregnant women were colonised with GBS. Invasive GBS infections incidence in infants (0.18/1000 live births) showed a decreasing trend (0.3 to 0.1/1000 live births). Type III was overrepresented in infants with invasive infections (n = 35, 58.3%), whereas type V predominated among colonised adults (n = 224, 25.5%) and those with noninvasive (n = 37, 32.5%) and invasive infections (n = 8, 40%). The hypervirulent clone III/ST17 was highly associated with invasive infections (n = 28, 35%), particularly late-onset disease (n = 9, 47.4%), showing an increase from 12.3 to 14.8%. The GBS resistance to erythromycin and clindamycin was 26.7% and 22.1%, respectively, with an upward trend. The emergence of the hypervirulent clone III/ST17 and the escalation in GBS resistance highlight an urgent need for continuous monitoring of GBS infections.

Genomic Characterization of Serotype III/ST-17 Group B Streptococcus Strains with Antimicrobial Resistance Using Whole Genome Sequencing

“…The prevalence of antibiotic resistance to clindamycin and erythromycin varies greatly in different geographic areas, with studies from Asia reporting a much higher resistance rate than Western countries [35,36]. The GBS resistance to erythromycin and clindamycin was 26.7-46% and 22.1-47%, respectively, with an upward trend [35][36][37]. No specific relationship between antibiotic resistance and specific serotypes was found in previous studies [30,[34][35][36].…”

Molecular epidemiology of Streptococcus agalactiae in non-pregnant populations: a systematic review

“…No study originated from the African, Eastern Mediterranean or Southeast Asian regions. Twelve studies [7, 14–16, 19, 21, 22, 25, 27–30] only investigated the genomic epidemiology of GBS in diseased adults, whereas the remaining considered GBS concomitantly in non-pregnant populations and neonates and/or pregnant women (8–11, 13, 17, 18, 20, 23, 26, 31–33; ). Overall, a total of 14 208 participants were described across the included studies, with a total of 14 110 GBS isolates being analysed.…”

Bacterial and Host Determinants of Group B Streptococcal Infection of the Neonate and Infant

“…In more recent studies interrogating invasive disease or GBS exposure in infants and neonates, proportions of EOD versus LOD varied greatly in each study ( Table 1 ). Most of the invasive isolates observed in these cohorts belong to serotype III (range 40.7–77.9%), with the next most common belonging to serotypes Ia/b or V ( Kang et al, 2017 ; Martins et al, 2017 ; Guan et al, 2018 ; Guo et al, 2018 ; Kao et al, 2019 ; Li et al, 2019 ; Wu et al, 2019 ; Plainvert et al, 2020 ; Awwad et al, 2021 ; Kekic et al, 2021 ; Lohrmann et al, 2021 ). Interestingly, serotype Ia (55.6%) and V (83.1%) were most common among the American and Icelandic infants, respectively, although in both cases serotype III was second ( Björnsdóttir et al, 2019 ; Nanduri et al, 2019 ).…”

“…Some guidelines also call for cephalosporins, vancomycin, clindamycin, or azithromycin for IAP in women with low or high risk of penicillin allergy ( Le Doare et al, 2017b ; Zhu and Lin, 2021 ). Resistance to cephalosporins (ceftriaxone and cefuroxime) and vancomycin were observed in a small study of Palestinian newborns and infants ( Awwad et al, 2021 ), while clindamycin resistance appears to be relatively common with consistently high rates in different geographical regions ( Martins et al, 2017 ; Guan et al, 2018 ; Guo et al, 2018 ; Kao et al, 2019 ; Li et al, 2019 ; Nanduri et al, 2019 ; Wu et al, 2019 ; Awwad et al, 2021 ; Kekic et al, 2021 ; Lohrmann et al, 2021 ). These findings highlight the importance of antibiotic susceptibility tests in clinical settings particularly when penicillin cannot be prescribed.…”