Characterization and Phylogenetic Analysis of Campylobacter Species Isolated from Paediatric Stool and Water Samples in the Northwest Province, South Africa

Abstract

Antibiotic-resistant Campylobacter could adversely affect treatment outcomes, especially in children. We investigated the antibiotic susceptibility profiles, virulence potentials and genetic relatedness of Campylobacter spp. from paediatric and water samples in the North West Province, South Africa. Overall, 237 human and 20 water isolates were identified using culture and real-time polymerase chain reaction (PCR). The antibiotic susceptibility profiles were determined using the disk diffusion method. Gradient strips were used to determine the minimum inhibitory concentration of each antibiotic. Antibiotic resistance (gryA, tetO and 23S rRNA 2075G and 2074C) and virulence (cadF and ciaB) genes were also investigated using PCR. A phylogenetic tree to ascertain the clonality between water and clinical isolates was constructed using MEGA 7. Overall, 95% (water) and 64.7% (human) of the isolates were resistant to at least one antibiotic tested. The highest resistance was against clarithromycin (95%) for water and ampicillin (60.7%) for human isolates. The 23S rRNA 2075G/2074C mutation was the most expressed resistance gene. Phylogenetic reconstruction revealed eight intermixed clades within water and human Campylobacter isolates. This study suggests the possible circulation of potentially pathogenic antibiotic-resistant Campylobacter in the Northwest Province, South Africa with drinking water being a possible vector for disease transmission in this area.

Campylobacteriosis Agents in Meat Carcasses Collected from Two District Municipalities in the Eastern Cape Province, South Africa

“…Multiple antibiotic resistance genes were highly detected in most of the isolates (Table 6), and this is in agreement with the multiple phenotypic resistance profiles displayed by the isolates (Table 5). Multiple resistance genes in the Campylobacter isolates were detected, and our results are in agreement with the reports of Chukwu et al [74] and Wieczorek et al [91]. There was a high rate of detection of resistance genes in chloramphenicol (catll (91.78%)), tetracycline (tetA (68.82%)), ciprofloxacin (gyra (61.76%)), ampicillin (ampC (55%)), gentamycin (aac(3)-IIa (aacC2) a (40.98%)), and tetracycline (tetM (38.71%) in the Campylobacter isolates.…”

“…Similarly, the high occurrence rate of the cadF (37.25%) gene and the lower prevalence of the flaA (1.96%) gene were detected in the Campylobacter isolates from meat samples, and these results are akin with the reports of Andrzejewska et al [77] and Ripabelli et al [78]. Our results also corroborated the report of Chukwu et al [74], who also detected the cadF gene in Campylobacter strains isolated from water and paediatric stools. The ciaB gene was screened for but was not detected, and our findings are contrary to the reports of Melo et al [79], Melo et al [80], and Zhong et al [81] who reported high detection rates of the ciaB gene in meats and in retailed food samples.…”

“…Though, what has been clear about Campylobacter infections and has been proposed as virulence determinants includes Campylobacter's invasive capability, adherence to intestinal mucosa, ability to produce toxins, and flagella-mediated motility [73]. Thus, the presence of these specific genes associated with Campylobacter invasion, adhesion, toxin production, and colonisation are all essential for the process of infection, and the mechanism by which they cause disease in humans is assumed to be multifactorial [74]. From the PCR results of the virulence gene assessed, most Campylobacter species were detected to harbour a high proportion of cadF, flaA, and iam genes responsible for colonisation, invasion, and adherence, and our results corroborate the report of Abu-Madi et al [75].…”

Mixed Aetiology of Diarrhoea in Infants Attending Clinics in the North-West Province of South Africa: Potential for Sub-Optimal Treatment

“…Genus-and species-specific primers were used for the identification of Campylobacter together with the cycling conditions have previously been described [101,102]. Additionally, the identification of Arcobacter to the genus level and the simultaneous identification of A. butzleri, A. cryaerophilus and A. skirrowii was as previously described by [103].…”

“…Isolates that harboured the mdh gene were tested for the presence of eight VGs-eaeA (EPEC/EHEC), eagg (EAEC), ipaH (EIEC), ST and LT (ETEC), stx1, stx2 and flicH7 (EHEC)-as previously described [106,107]. All the PCR assays included a positive control consisting of DNA from a reference strains obtained from the Microbiology Laboratories of the Natural Resources and the Environment (NRE) and CSIR, as well as previously characterised by Abia et al [101]. A reaction mixture void of template DNA was also included in each PCR assay as a no template control.…”