Molecular identification of Sarcocystis species in raw hamburgers using PCR-RFLP method in Kashan, central Iran.

The prevalence of bovine Sarcocystosis is high in the most regions of the world. It can be a human health problem due to consumption of raw or under cooked hamburgers or other bovine meat products. This study was carried out to investigate the prevalence and species identification of Sarcocystis among of hamburgers, using PCR-RFLP methods in Kashan, central Iran. Overall 200 raw industrial hamburgers samples with at least 60% meat were randomly collected from nine different brands in Kashan, central Iran. The genomic DNA was extracted and a PCR-RFLP method was used to amplify an approximately 900 bp fragment at the 18S rRNA(SSU) gene, restriction enzyme BclI was used for species identification. The results showed that 58 (29%) of 200 tested hamburger samples were infected to Sarcocystis spp. The prevalence rate was 31.25 and 26.9% in the hamburgers with 90 and 60-75% meat, respectively. According to PCR-RFLP analysis, 43 (74.1%) of the 58 isolates were Sarcocystis cruzi , 12 (20.7%) showed co-infection to S. cruzi and Sarcocystis hirsuta , 2 (3.5%) was mixed infected to S. cruzi and Sarcocystis hominis , 1 (1.7%) showed the pattern of mix infection to three species. This study revealed one-third of industrial hamburger were infected to S. cruzi or mixed infection of S. cruzi with other bovine sarcocytosis. To prevent cattle infection, the possible ingestion of the disposal sporocyst stage from dogs must be eliminated. Although in this study, the prevalence of S. hominis was low and cannot be considered as a major zoonosis, it should be recommended avoiding eating under cooked hamburger and other bovine meat products to prevent human infection.