Serosurvey and molecular detection of the main zoonotic parasites carried by commensal Rattus norvegicus populations in Tehran, Iran

Abstract Background: Rattus norvegicus are reservoirs of various zoonotic parasites that have become a global public health concern. Considering the distribution of Rattus norvegicus throughout Tehran, this study aims to assess the frequency of zoonotic parasites carried by commensal rodents in Tehran, Iran.Methods: The study considered five regions (North, South, West, East, and center) of Tehran as case studies. The serological method was used for detecting antibodies against Trichomonas vaginalis , Babesia spp, and Cryptosporidium spp using a commercial qualitative rat ELISA kit. The frequency of Toxoplasma gondii was surveyed by the conventional PCR method. Furthermore, nested PCR was used to detect Giardia spp and Leishmania spp in commensal Rattus norvegicus in Tehran.Results: Approximately, 76% of 100 Rattus norvegicus tested were infected with at least one zoonotic parasite, which demonstrates the significant frequency of parasites within the study areas. Seroreactivity against Trichomonas vaginalis , Babesia spp, and Cryptosporidium spp was detected in 5%, 0%, and 1% of Rattus norvegicus tested, respectively. Toxoplasma gondii DNA was detected in 32 out of 100 (32%) Rattus norvegicus , and Leishmania spp and Giardia spp DNA were found in 18 out of 100 (18%) and 76 out of 100 (76%) Rattus norvegicus investigated, respectively.Conclusion: The findings indicate a wide geographical dissemination of Giardia spp, Toxoplasma gondii , and Leishmania spp DNA in Rattus norvegicus within five districts of Tehran. In contrast, other parasites such as Cryptosporidium spp infection rarely occurred in Rattus populations. No evidence for the circulation of Babesia spp was found in this study.