BackgroundFoods with animal origins and particularly milk play a considerable role in transmission of Helicobacter pylori. The current study was performed to assess phenotypic characters of antibiotic resistance and genotyping pattern of vacA, cagA, iceA, oipA and babA2 alleles amongst the H. pylori strains isolated from raw milk.MethodsSix-hundred and thirty raw milk samples were collected and cultured on Wilkins Chalgren anaerobe media. Antibiotic resistance and genotyping patterns were studied using disk diffusion and PCR, respectively.ResultsSixty-seven out of 630 (10.63%) raw milk samples were positive for H. pylori. Ovine raw milk (17.27%) samples had the highest prevalence of H. pylori, while camel (5.00%) had the lowest. H. pylori strains harbored the highest prevalence of resistance against ampicillin (82.08%), tetracycline (76.11%), amoxicillin (74.62%), metronidazole (65.67%) and erythromycin (53.73%). Prevalence of resistance against more than 10 types of antibiotics was 17.91%. VacA s1a (83.58%), m1a (80.59%), s2 (77.61%) and m2 (68.65%), cagA (73.13%) and babA2 (44.77%) were the most commonly detected genotypes. We found that S1am1a (56.71%), s2m1a (56.71%), s1 am2 (43.28%) and s2 m2 (43.28%) were the most commonly detected genotyping pattern. Frequency of cagA-, oipA- and babA2- genotypes were 26.86%, 62.68% and 55.22%, respectively. We found that S1a/cagA+/iceA1/oipA−/babA2- (28.35%), m1a/cagA+/iceA1/oipA−/babA2- (28.35%) and s2/cagA+/iceA1/oipA−/babA2- (26.86%) were the most commonly detected combined genotyping pattern.ConclusionsSimultaneous presence of vacA, cagA, iceA, oipA and babA2 genotypes in antibiotic resistant H. pylori strains indicates important public health issue regarding the consumption of raw milk. However, additional researches are required to find molecular genetic homology and other epidemiological aspects of H. pylori in milk.

Dairy products play a considerable role in transmission of Helicobacter pylori. The current study was done to assess phenotypic characters of antimicrobial resistance and genotyping pattern of vacA, cagA, and iceA alleles among the H. pylori strains isolated from dairy products. Eight‐hundred dairy samples were collected and cultured. Antimicrobial resistance and genotyping patterns were assessed using disk diffusion and polymerase chain reaction, respectively. Thirty‐one out of 800 (3.87%) traditional dairy product samples were positive for H. pylori. Cheese (11.53%) samples had the highest incidence of H. pylori, while yoghurt (1.11%) had the lowest. Helicobacter pylori strains harbored the highest incidence of resistance against ampicillin (93.54%), amoxicillin (93.54%), tetracycline (90.32%), erythromycin (80.64%), and metronidazole (77.41%). VacA s1a (90.32%), m1a (90.32%), s2 (80.64%) and m2 (77.19%), cagA (51.61%), and iceA1 (32.25%) were the most routinely identified genotypes. S1am1a (67.74%), s2m1a (64.51%), and s1am2 (51.61%) were the most routinely identified genotyping pattern. Simultaneous presence of vacA, cagA, and iceA genotypes in antimicrobial resistant H. pylori strains indicates important public health issue regarding the consumption of dairy products. However, additional researches are required to find molecular genetic homology and other epidemiological aspects of H. pylori in dairy products. Practical applications Due to the high consumption rate of dairy samples, they should have a high microbial quality. Foods with animal origins and especially dairy samples are considered as a probable source of Helicobacter pylori infections. The incidence of contamination of dairy samples by H. pylori is fairly high, and nearly all of the isolates exhibited resistance against several types of antimicrobials and harbored pathogenic vacA, cagA, and iceA genotypes, so the risk of probable foodborne diseases caused by H. pylori in such products should not be neglected. Additionally, dairy samples may act as a reservoir of H. pylori with ability to transfer antimicrobial resistance and virulent genotypes.