elahe ghorbani marghmaleki

Campylobacter spp. are the main cause of human gastroenteritis. The 16SrRNA sequencing is one of fast molecualr method to detect this fastidious. In this study, we compared the sequencing of 16srRNA genewith four housekeeping genestodetect Campylobacter spp. in patients with diarrhea and healthy people.

60 samples of Campylobacter DNA extracted from stool samples of 30 patients with diarrhea and 30 healthy people were used. In order to detect Campylobacter, we designed primers for proliferation of 16SrRNA, cadF, dnaJ, slyD, and rpoA genes using Primer 3, Mega 4.0 and Blast software. Then the PCR products were sequenced using ABI system.

The sequencing showed concordance of PCR-products with deposited sequences in the Gene Bank. Among diarrhea patients, 53.3% of samples were significantly (p< 0.05) positive for slyD and cadF genes and 50% of samples were positive using 16SrRNA, rpoA, and dnaJ genes by PCR assay. The average of sensitivity and specificity were found 53.33% and 83.33%, respectively.

Due to various copies of repeated sequences of 16SrRNA gene, analyzing its amplicons on electrophoresis may be more difficult than the slyD and cadF genes. According to our results, among the 5 studied genes; the highest detection rate was related to slyD and cadF genes. Although, dnaJ and rpoA genes, instead of 16SrRNA gene, can be considered as appropriate genes for molecular detection of Campylobacter bacteria.

Thermophilic Campylobacter is the first cause of gastroenteritis infection in human. Nowadays, the prevalence of Campylobacter spp. is higher than other bacteria causing intestinal infection such as Salmonella and Shigella. This study was designed to compare the frequency of Campylobacter species in poultry slaughterhouse workers and poultry meat sellers (exposed group) and in healthy people (non-exposed group) in Arak city. Among the 104 samples, 52 samples were collected from the slaughterhouse workers and poultry meat sellers, and 52 samples were collected from the control group. The stool samples were taken from the slaughterhouse workers, poultry meat seller, and healthy people who had not received antibiotics for the last two weeks. For enrichment, the samples were enriched in Preston broth medium at 37℃ for 48 hrs under the microaerophilic conditions. Then they were sub cultured using a passive filtration method on Brucella agar at 37℃ for 72 hrs under the microaerophilic conditions. Finally, the samples were directly tested using genus- and species specific PCR primers. Of 52 samples collected from the slaughterhouse workers and poultry meat sellers, 11 (21.1%) samples were positive for the presence of Campylobacter spp. by PCR, and of 52 samples collected from the healthy people, 2 (3.8%) samples were reported as positive. The most frequent species isolated from the 2 groups were C.jejuni (53.84%) and C.coli (23.07%), respectively. Chicken is identified as one of the important sources of Campylobacter infections in humans, which may contaminate poultry Slaughterhouse workers and chicken meat sellers, which in turn, they could potentially transmit Campylobacter strains to healthy people and chicken meat.