somaye kermani

Vibrio cholerae is one of the important human pathogens that is transmitted through contaminated water and food. In Qom province, due to special weather conditions, diseases caused by Vibrio cholerae are endemic. The aim of this study was the prevalence of Vibrio cholerae in water and vegetables of Qom province and the presence of two virulence genes, hlyA and toxR. During two years (2020-2021), 120 samples of agricultural water (70) and vegetables (50) in Qom province were collected. The samples were cultured on specific media. Suspicious colonies were evaluated by Gram staining and biochemical tests and the serotype Vibrio cholerae was identified by serology test. Finally, Then, the presence of virulence genes was investigated by PCR method and also the antibiotic resistance pattern by disk diffusion method was evaluated in the isolates.  Vibrio cholera bacteria were isolated from 17 samples (16.14%), all of which were Non-O1. The rate of contamination of water and vegetables was 28.14% (10 cases) and 14.00% (7 cases), respectively. In molecular evaluation, the abundance of virulence genes including: toxR (88.32%), rtxA (58.82%), hlyA (47.05%), chxA (5.88%), and 100% of isolates did not have ctxA, ace and tcpA genes. The most antibiotic resistance is related to ampicillin and amoxicillin (34.29%), followed by cefuroxime (17.46%), imipenem (11.76%), and cefoxitin and trimethoprim-sulfamethoxazole (5.88%). The results of this study showed that Vibrio cholerae Non-O1 is present in water and vegetables of Qom province, and as an important source of disease for humans therefore, continuous health monitoring of water and vegetables and proper disinfection of these foods is very important.

Helicobacter pylori is a gram-negative, micro-aerophilic, and spiral-shaped bacillus. Infection with this bacterium can lead to gastritis, ulcers, and even gastric cancer. This study was conducted to evaluate the presence of the cagA gene among patients with gastritis and gastric cancer.

This study was performed in patients with gastritis (n=40) and gastric cancer (n=40). Presence of H. pylori infection in gastritis specimens and in cancerous tissues was investigated by urease test and Giemsa staining, respectively. Using PCR, 16S rRNA and cagA genes were investigated.

Pain and weight loss were the most common complaints of patients. Dyspepsia and duodenal ulcer were the most frequent endoscopic findings. According to pathologic results, intestinal-type G1 adenocarcinoma was detected in most cases. All positive-H. pylori cases were also positive for 16S rRNA. The cagA gene in patients with gastritis and stomach cancer was present in 13 (32.5%) and 11 (27.5%) cases, respectively.

Compared to other studies, low presence of the cagA gene in Qom could be an indication of less virulent strains in this province, but, further studies are recommended to evaluate other genes.