Seroprevalence of Toxoplasma gondii Among Wild Rats (Rattus rattus) in Ahvaz District, Southwestern Iran

Background: The protist pathogen Toxoplasma gondii infects humans and other animals such as wild rats (Rattus rattus) worldwide. Wild rats are infected with T. gondii due to ingestion of food or water contaminated with oocysts and may play an important role in the transmission of T. gondii infection to humans. Objectives: The aim of the present study was to determine the seroprevalence of T. gondii among wild rats in Ahvaz district, southwestern Iran. Materials and Methods: We determined the seroprevalence of T. gondii among wild rats (R. rattus) in Ahvaz district between February 2008 and January 2011. Immunochromatographic assay (ICA) to detect serum antibodies against T. gondii was performed for 127 adult wild rats. The rats were captured in cages and brought alive to the Veterinary Hospital of Shahid Chamran University. The rats were classified according to sex and season and region of capture. The results were analyzed by Chi-square analysis and Fisher’s exact test. Results: Thirty-one of the 127 serum samples (24.41%) had antibodies against T. gondii (95% Confidence interval; 16.9–31.9%). Prevalence was higher in female rats (24.66%) than in male rats (24.07%). The rats caught during summer (34.48%) and in the east region of Ahvaz district (36.36%) showed high prevalence. However, the gender, season and region of collection did not significantly affect the prevalence of infection (P > 0.05). Conclusions: Our study showed that the seroprevalence of T. gondii was relatively high (24.41%) among wild rats in the Ahvaz district of Iran. The high prevalence of T. gondii infection in rodents may be of epidemiological importance as infected rodents are a potential route for T. gondii transmission to Felidae via ingestion of tissue cysts