Prevalence of the M1UK sublineage among emm1 Streptococcus pyogenes invasive strains isolated in the Czech Republic from December 2022 to May 2023.

Výskyt sub-linie M1 UK mezi invazivními kmeny Streptococcus pyogenes typ emm1 izolovanými od prosince 2022 do května 2023 v České republice.

Publisher: Ceská lékarská spolecnost J.E. Purkyne Country of Publication: Czech Republic NLM ID: 9431736 Publication Model: Print Cited Medium: Print ISSN: 1210-7913 (Print) Linking ISSN: 12107913 NLM ISO Abbreviation: Epidemiol Mikrobiol Imunol Subsets: MEDLINE

Original Publication: Praha : Ceská lékarská spolecnost J.E. Purkyne, c1994-

Streptococcus pyogenes*/genetics ; Streptococcus pyogenes*/isolation & purification ; Streptococcal Infections*/microbiology ; Streptococcal Infections*/epidemiology ; Antigens, Bacterial*/genetics ; Carrier Proteins*/genetics ; Bacterial Outer Membrane Proteins*/genetics; Humans ; Czech Republic/epidemiology ; Adolescent ; Child ; Adult ; Child, Preschool ; Middle Aged ; Prevalence ; Young Adult ; Bacterial Proteins/genetics ; Infant ; Female ; Male ; Exotoxins/genetics ; Aged

Aims: Since December 2022, an increase in invasive disease caused by Streptococcus pyogenes has been observed in the Czech Republic, with a shift in the clinical presentation and age of patients. Unlike in previous years, invasive disease is more common in children and adolescents under 18 years of age and in previously healthy middle-aged adults. An increase has been noticed in the number of S. pyogenes isolates from primarily sterile sites such as haemoculture, cerebrospinal fluid, pleural effusion fluid, joint fluid, and postmortem specimens. Routine emm gene typing revealed emm1 to be the predominant emm type of S. pyogenes. Between January 2023 and July 2023, 46% of all S. pyogenes isolates from invasive cases were assigned to the emm1 type. The globally spread M1UK sublineage is characterized by differences in the expression of seven genes, including the streptococcal pyrogenic toxin A (speA) gene, compared to historical emm1 iGAS strains. The aim of this study is to determine whether the more toxigenic M1UK sublineage is associated with the increase in invasive disease in the Czech Republic.
Methods: Whole genome sequencing of 41 S. pyogenes isolates from patients with invasive disease recovered in the Czech Republic in 2018 and 2019 and from December 2022 to May 2023 was performed using the MiSeq instrument (Illumina). Bioinformatics analysis was performed using freely available online tools the Bacterial and Viral Bioinformatics Resource Center.
Results: Based on whole genome sequencing data of 41 emm1 isolates of S. pyogenes from patients with invasive infectious disease recovered in 2018 and 2019 and from December 2022 to May 2023, the M1UK sublineage was found to be predominant from December 2022 to May 2023.
Conclusion: The reason for the spread of the M1UK sublineage in the Czech Republic late in 2022 and in the first half of 2023 is not entirely clear, but it may be related to reduced immunity due to limited GAS transmission during lockdowns, especially in children. Another factor that may have contributed to the high incidence of invasive infectious diseases is the seasonal circulation of respiratory viruses.

Keywords: GAS; Phylogenetic analysis; Streptococcus pyogenes; outbreak iGAS; superantigen; whole genome sequencing

0 (Antigens, Bacterial)
0 (Carrier Proteins)
0 (streptococcal M protein)
0 (Bacterial Outer Membrane Proteins)
0 (Bacterial Proteins)
0 (Exotoxins)

Date Created: 20240726 Date Completed: 20240727 Latest Revision: 20240904

20240904

10.61568/emi/11-6306/20240424/137080

39060098