Prevalence and Genotyping of <i>Helicobacter pylori</i> Isolated From Meat, Milk and Vegetable in Iran

Abstract

Background: Despite the considerable clinical role of Helicobacter pylori, its certain routes of transmission and origin have not been reported. Based on the argumentative hypothesis, foods play an imperative role in the spread of H. pylori to humans. Objectives: The current research was done to investigate the prevalence rate and distribution of Vacuolating Cytotoxin A and Cytotoxin Associated Gene A genotypes in the H. pylori strains isolated from meat, milk, and vegetables. Methods: A total of 340 food samples were collected and directly moved to the laboratory. Samples were cultured and H. pylori colonies were approved using the gram staining, urease test, and 16s rRNA-based polymerase chain reaction (PCR) amplification. Positive strains were tested for distribution of vacA and cagA genotypes using the multiplex-PCR. Results: Out of 340 samples, 40 (11.76%) harbored H. pylori. Prevalence of H. pylori in meat, milk, and vegetable samples were 7.33%, 16%, and 12.50%, respectively. Ovine milk (26%) was the most commonly contaminated sample. The most commonly detected genotypes were vacA s1a (87.50%), vacA m1a (87.50%), vacA s2 (82.50%), cagA (80%), and vacA m2 (62.50%). Genotypes of S1am1a (62.50%), s2m1a (55%), s1am2 (50%), s2m2 (45%), and m1am2 (42.50%) were the most commonly detected combined genotypes. Conclusions: Milk, vegetables, and meat, are latent sources of H. pylori. Similarity in the genotyping pattern of H. pylori strains of various samples represents their similar sources of infection. Further studies are required for finding the exact sources of H. pylori strains.