Genotyping of Helicobacter pylori strains isolated from raw milk and dairy products

Subject Areas : Food Microbial Contamination

Soolmaz Mousavi ¹ , Farhad Safarpoor Dehkordi ² , Yousef Valizadeh ³

1 - Young Researchers and Elites Club, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.
2 - Young Researchers and Elites Club, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.
3 - Young Researchers and Elites Club, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.

Received: 2017-04-15 Accepted : 2017-08-23 Published : 2017-11-22

Keywords: Milk, Helicobacter pylori, Dairy products, genotyping,

Abstract :

So far, transmission pathways and epidemiological aspects of Helicobacter pylori are not identified well. Role of water and food materials in transmission of Helicobacter pylori to human is probable. The present study was carried out to genotyping of Helicobacter pylori strains isolated from the samples of raw milk and dairy products collected from Isfahan province. In total, 250 samples of milk and dairy products were collected and transferred to the laboratory. DNA extraction was done and detection of 16S rRNA gene of the Helicobacter pylori was performed using from the PCR test. Positive samples were analyzed for presence of various genotypes of VacA and CagA. From a total of 250 samples of milk and dairy products, 37 samples (14.8%) were infected with Helicobacter pylori. Sheep milk had the highest (25%) and traditional cheese (2%) had the lowest rate of infection. Statistically significant difference was seen between the type of sample and prevalence rate of Helicobacter pylori. VacA s1a (27.02%), VacA m1a (24.32%) and CagA (21.62%) were the most frequently detected genotypes. S1am1a (16.21%) and s1am2 (5.40%) genotypes had the highest frequency amont combined genotypes. Genotypic similarity of Helicobacter pylori strains of various samples represented their similar source of infection. Genotypic similarity pattern of our study and conducted studies on clinical samples of human represented transmission of Helicobacter pylori strains from infected staffs of milking and saling of milk and dairy products to samples.