Epidemiology of Campylobacter Infections among Children in Egypt

Abstract

Campylobacter is a frequently isolated bacterial pathogen among children with diarrhea. Data are lacking on the distribution and spectrum of disease associated with Campylobacter species and Campylobacter jejuni capsular polysaccharide (CPS) types. This information is essential because current vaccine research seeks to target specific CPS types. An effective CPS-conjugate vaccine will need to cover CPS types that are both common and associated with severe disease. The US Naval Medical Research Unit-3 conducted several prospective cohort studies researching diarrheal disease in Egypt from 1995 to 2003. In total, 1,057 children were enrolled and followed to a maximum age of 36 months. We analyzed Campylobacter-positive stool samples that were collected while subjects were symptomatic, along with corresponding clinical data. Of 441 Campylobacter isolates, 322 represented primary infections (189 C. jejuni, 127 Campylobacter coli, six unspeciated). There were 19 C. jejuni CPS types identified; eight accounted for 63.5% of primary C. jejuni infections. We also screened for the presence of the type-6 secretion system (T6SS), a putative virulence determinant. The T6SS was found in 18.0% of C. coli isolates and 57.6% of C. jejuni isolates (P < 0.001), and was not uniformly distributed among CPS types (P < 0.001). Strains with the T6SS were not associated with more severe disease. Clinical presentations across species and CPS types appeared similar. This study adds to the growing epidemiological data and also provides some analysis of the clinical spectrum associated with infection by specific Campylobacter species, C. jejuni capsule types, and possible virulence determinants.

Distribution of genes related to Type 6 secretion system and lipooligosaccharide that induced ganglioside mimicry among Campylobacter jejuni isolated from human diarrhea in Thailand

“…The hcp gene was associated with 10 capsule types of C. jejuni isolates whereas a variable hcp prevalence was reported by others. Sainato et al [43] reported a hcp gene prevalence of 33.3% in HS2 isolates, but up to 86.2% was noted in this study. Moreover, numbers of hcp-C. jejuni isolates were more significant in children than travelers (22.2%, 86.7%; p = 0.0001), especially in HS8/17 isolates.…”

“…None of the T6SS genes were detected in 34 C. jejuni isolated from human diarrheal cases in Pakistan [29]. In our study, hcp was found in 62.6% of the 524 cases, and this proportion was similar to studied isolates in Vietnam (60.6%) and Egypt (57.6%) [28,43].…”

“…This is similar to the finding by Agnetti et al [44], where no significant difference in the clinical manifestations and the course of disease between patient with hcppositive and -negative C. jejuni isolates. Similarly, the presence of hcp gene in C. jejuni and C. coli from stool did not have any significant association to clinical outcome in Egyptian children [43].…”

Isolation and molecular characterization of Campylobacter jejuni from chicken and human stool samples in Egypt

“…Generally, Campylobacter is the most common bacterium that causes gastroenteritis globally in humans and can be lethal to young children, geriatric patients and immunocompromised patients (Sainato et al, 2018).…”

One health approach of campylobacteriosis in Egypt: An emerging zoonotic disease

“…Recently, the epidemiology of Campylobacter among an Egyptian pediatric population was described and the results pointed out to the variability in Campylobacter spp. and C. jejuni capsular polysaccharide (CPS) diversity in this population; furthermore, the high prevalence of type-6 secretion system (T6SS) among C. jejuni isolates as there was no significant associations between clinical illness and Campylobacter spp., C. jejuni CPS types, or suspected virulence factors [12].…”