Publications by authors named "Y Kazawa"
Article Synopsis
- The study investigates the decline of streptococcal toxic shock syndrome (STSS) cases in Japan, particularly its connection to group A Streptococcus (GAS) strains, and aims to understand the reasons behind this decrease.
- Researchers analyzed 526 GAS isolates from STSS patients between 2019 and 2022, noting a significant decrease in the prevalence of emm1 strains after the COVID-19 pandemic began.
- The findings suggest that changes in public health measures during the pandemic, such as mask-wearing, may have reduced infections, particularly those from strains linked to pharyngeal infections, contributing to the reduction in STSS cases.
The incidence of streptococcal toxic shock syndrome (STSS) due to group B Streptococcus (GBS) has been increasing annually in Japan and is becoming a serious challenge. Furthermore, in recent years, penicillin- or clindamycin-resistant strains used in treating streptococcal toxic shock syndrome have been reported. However, no report analyzed >100 isolates of group B Streptococcus causing streptococcal toxic shock syndrome.
View Article and Find Full Text PDFBackground: Streptococcus dysgalactiae subspecies equisimilis (SDSE) has emerged as an important cause of severe invasive infections including streptococcal toxic shock syndrome (STSS). The present study aimed to identify genes involved in differences in invasiveness between STSS and non-invasive SDSE isolates.
Methods: STSS and non-invasive SDSE isolates were analysed to identify csrS/csrR mutations, followed by a comparative analysis of genomic sequences to identify mutations in other genes.
Streptococcal toxic shock syndrome (STSS) is a severe invasive infection characterized by the sudden onset of shock, multi-organ failure, and puerperal sepsis and shows high mortality. Its primary cause is group A streptococcus (GAS, Streptococcus pyogenes). In this study, we genotyped the cell-surface M virulence protein gene (emm) from 621 GAS isolates obtained from patients with STSS in Japan in 2013-2018 and performed antimicrobial susceptibility testing using the broth microdilution method.
View Article and Find Full Text PDFArticle Synopsis
- Invasive infections caused by 89 strains, particularly from clade 3, are on the rise globally, including in Japan where specific features of these strains are largely unknown.
- This study analyzed 89 STSS isolates and 72 non-STSS isolates from Japan (2011-2019) using whole-genome sequencing, revealing that most belonged to clade 3, regardless of whether they caused severe disease.
- The research also identified critical factors associated with invasive disease in these strains, such as specific mutations and the absence of a gene for hyaluronidase, contributing to our understanding of their genetic characteristics.