High prevalence of Campylobacter jejuni CC21 and CC257 clonal complexes in children with gastroenteritis in Tehran, Iran

Abstract

Background Campylobacter jejuni (C. jejuni) is a leading cause of acute gastroenteritis in human worldwide. The aim of study was to assess the distribution of sialylated lipooligosaccharide (LOS) classes and capsular genotypes in C. jejuni isolated from Iranian children with gastroenteritis. Furthermore, the level of dnaK gene expression in C. jejuni strains with selected capsular genotypes and LOS classes was intended. Moreover, a comprehensive study of C. jejuni MLST-genotypes and inclusive comparison with peer sequences worldwide was intended. Methods Twenty clinical C. jejuni strains were isolated from fecal specimens of 280 children aged 0–5 years, suspected of bacterial gastroenteritis, which admitted to 3 children hospitals from May to October, 2018. Distribution of sialylated LOS classes and specific capsular genotypes were investigated in C. jejuni of clinical origin. The expression of dnaK in C. jejuni strains was measured by Real-Time-PCR. MLST-genotyping was performed to investigate the clonal relationship of clinical C. jejuni strains and comparison with inclusive sequences worldwide. Results C. jejuni HS23/36c was the predominant genotype (45%), followed by HS2 (20%), and HS19 and HS4 (each 10%). A total of 80% of isolates were assigned to LOS class B and C. Higher expression level of dnaK gene was detected in strains with HS23/36c, HS2 and HS4 capsular genotypes and sialylated LOS classes B or C. MLST analysis showed that isolates were highly diverse and represented 6 different sequence types (STs) and 3 clonal complexes (CCs). CC21 and CC257 were the most dominant CCs (75%) among our C. jejuni strains. No new ST and no common ST with our neighbor countries was detected. Conclusions The C. jejuni isolates with LOS class B or C, and capsular genotypes of HS23/36, HS2, HS4 and HS19 were dominant in population under study. The CC21 and CC257 were the largest CCs among our isolates. In overall picture, CC21 and CC353 complexes were the most frequently and widely distributed clonal complexes worldwide, although members of CC353 were not detected in our isolates. This provides a universal picture of movement of dominant Campylobacter strains worldwide.

Local accessory gene sharing among Egyptian Campylobacter potentially promotes the spread of antimicrobial resistance

“…Although one isolate in our collection was from ST-45 CC, this host generalist CC is often one of the most commonly isolates lineages in clinical surveillance studies worldwide [6,[101][102][103]. Notably, however, it is often absent (or under-represented) in studies conducted in LMICs [71,104,105]. This is consistent with observations from other LMICs, where local differences in disease epidemiology are reflected by the absence of common Campylobacter lineages, and the presence of rare or unique STs [71,[106][107][108].…”

Local accessory gene sharing drives lineage-specific acquisition of antimicrobial resistance in Egyptian Campylobacter spp.

“…Although one isolate in our collection was from ST-45 CC, this host generalist clonal complex is often one of the most commonly isolates lineages in clinical surveillance studies worldwide (De Haan et al, 2010;Shin et al, 2013;Sopwith et al, 2008). Notably however, it is often absent (or under-represented) in studies conducted in LMICs (Pascoe et al, 2020;Sarhangi et al, 2021). This is consistent with observations from other LMICs, where local differences in disease epidemiology are reflected by the absence of common…”

Monitoring AMR in Campylobacter jejuni from Italy in the last 10 years (2011–2021): Microbiological and WGS data risk assessment

“…Several studies were performed in Italy and show how common this CC is not only in chickens but also in strains isolated from turkeys, cattle and bulk tank milk (Lo Schiavo et al., 1991 ; Bianchini et al., 2014a , b ). The most common CC among chicken C. jejuni isolates was the CC‐21 according to that documented worldwide (Pezzotti et al., 2003b ; EFSA and ECDA, 2014 ; Lucarelli et al., 2016 ; Cito et al., 2018 ; Sarhangi et al., 2021 ). CC‐828 was also described as predominant and with similar results to CC‐21 and shared between chicken and human campylobacteriosis (Pezzotti et al., 2003a ).…”

“…Thus, next‐generation sequencing (NGS) tools and whole genome sequencing (WGS) in particular, provide a powerful approach for epidemiological trace‐back efforts (On, 2005 ). The tracking and tracing of living animals and animal‐derived food within the food chain is part of the monitoring process (Harlizius et al, 2004 ; Sarhangi et al., 2021 ). In addition to epidemiological tracing, NGS provides additional data to investigators that can include identification of specific markers for detection efforts and assessment of unique virulence factors that may be strain specific.…”