Identification of Sarcocystis spp. in Hamburgers Distributed in Fouman City, North of Iran Using Dab Smear and Digestion Methods

Abstract

Introduction: Human infection with Sarcocystis species can be attributed to the consumption of raw or inadequately cooked meat, such as hamburgers, containing encapsulated parasites.  Materials and Methods: This cross-sectional study was conducted between April and September 2022 in Fouman, Iran. A total of 182 hamburger samples, comprising two types of traditional hamburgers and industrial hamburgers, were collected. Result: Out of 182 hamburger samples of different types, 34% of them were found to be infected with Sarcocystis spp. The infection rate within industrial and traditional hamburgers was 21.5% and 56%, respectively. Notably, a statistically significant difference was observed between Sarcocystis-infested traditional and industrial hamburgers (p < 0.05). Among the two distinct groups of 182 hamburgers, the microscopic digestion method revealed the presence of Sarcocystis bradyzoites in all 51 infected traditional beef burgers and 19 positive industrial beef burgers. However, in the dab smear method, just 33 and 12 positive samples were respectively identified in traditional and industrial beef burgers and a statistically significant difference was observed between efficiency of these two methods (p < 0.05). Infection with macroscopic parasite cysts was not observed in any of hamburger samples. Similarly, no statistically significant association was identified between the meat content percentage and the infection rate in industrial hamburgers (p > 0.05).  Conclusion: Considering the high abundance of Sarcocysts micro cysts in frozen raw hamburgers, it is recommended to fully cook this food product and avoid consumption when only partially cooked.