Prevalence of Toxoplasma gondii infection in Myocastor coypus in a protected Italian wetland

BACKGROUND: Toxoplasma gondii is the causative agent for a major zoonosis with cosmopolitan distribution. Water has been implicated in outbreaks of toxoplasmosis in recent years. Coypus (Myocastor coypus), commonly nutria, are large semi-aquatic invasive rodents, naturalized throughout European countries, including most wetlands of Central Italy. The habitat of these animals is both terrestrial and aquatic, making them a species highly exposed to the parasite. FINDINGS: The occurrence of the infection was evaluated using a modified agglutination test (MAT) in 74 adult coypus from a naturalized population living in a wetland of Central Italy. Nested PCR (n-PCR) assay was carried out on some of them. Positive T. gondii MAT results were found in 44 animals (59·4%), 30 males (68·2%) and 14 females (31·8%). Antibody titers were ranging from 20 to 40960, while 12 out of 23 (52·2%), examined animals, 8 males (66·7%) and 4 females (33·3%), resulted positive to n-PCR. All n-PCR positive animals were seropositive, showing antibody titers ranging from 640 to 40960. CONCLUSIONS: Our results indicate that examined animals are heavily parasitized with Toxoplasma. This suggests that coypus could be a reservoir of this parasite, because they can be eaten both by scavenger animals and by humans, and that these animals would play a role in maintaining the cycle of T. gondii.