Molecular Characterization of Cryptosporidium spp. in Wild Rats of Tehran, Iran Using 18s rRNA Gene and PCR_RFLP Method

Background: Wild Rats have been implicated as potential reservoirs of Cryptosporidium spp., thereby responsible for transimission of the infection to humans by acting as natu- ral sources of C. parvum, a zoonotic species. Recently, and possibly due to much closer and more frequent contacts to these animals, concerns have raised about spread of the disease among human environments. Objectives: The purpose of this study is molecular characterization of Cryptosporidium in rats of Tehran. Materials and Methods: Rats were hunted randomly from diferent zones of Tehran and their stool samples were studied by Polimerase Chain Reaction (PCR) method us- ing 18s rRNA gene. Subsequently, positive (i.e. infected) samples were characterized and sequenced. Results: Reported rates of Cryptosporidium infection among 77 rats by implementation of staining as well as nested PCR methods were %13 and 27.3 %, respectively. In order to recognize type of infective agent, all positive cases were tested by PCR – RFLP (Restriction Fragment Length Polyformism) method by which C. parvum pattern was obsereved. . The obsereved patten inPCR-RFLP test was checked via sequence determination method in all positive isolations and the results were approved. Conclusions: The results reveal that wild rats in Tehran are reservoirs of C. parvum that could be transmitted to humans. Also, it illuminates hygienic importance of freewild- rats eradication throughout the city.