Toxoplasma gondii infection in wild mustelids and domestic cats across an urban-rural gradient from Southern Chile

Authors: BARROS, MACARENA - Universidad Andres Bello (UNAB); CABEZON, OSCAR - Autonomous University Of Barcelona; Dubey, Jitender; ALMERIA, SONIA - Autonomous University Of Barcelona; RIBAS, MARIA - Autonomous University Of Barcelona; ESCOBAR, LUIS - University Of Minnesota; RAMOS, BARBARA - Universidad Andres Bello (UNAB); MEDINA-VOGEL, GONZALO - Universidad Andres Bello (UNAB)

Submitted to: PLoS Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/31/2018
Publication Date: 6/20/2018
Citation: Barros, M., Cabezon, O., Dubey, J.P., Almeria, S., Ribas, M., Escobar, L., Ramos, B., Medina-Vogel, G. 2018. Toxoplasma gondii infection in wild mustelids and domestic cats across an urban-rural gradient from Southern Chile. PLoS Pathogens. https://doi.org/10.1371/journal.pone.0199085.
DOI: https://doi.org/10.1371/journal.pone.0199085

Interpretive Summary: Toxoplasma gondii is a single-celled parasite of all warm-blooded hosts worldwide. It causes mental retardation and loss of vision in children, and abortion in livestock. Cats are the main reservoir of T. gondii because they are the only hosts that can excrete the resistant stage (oocyst) of the parasite in the feces. Humans become infected by eating under cooked meat from infected animals and food and water contaminated with oocyst. Assessing environmental contamination with oocysts is technically difficult because of low numbers of oocysts in food and water. Marine mammals are useful indicators of contaminants in sea. Here, authors found antibodies to T. gondii in 59% of 73 American mink, 77% of 13 Southern river otters, 68% of 65 domestic cats and in two of two kodkods (Leopardus guigna), a wild felid species in South America. T. gondii DNA was detected in tissues from one American mink and one Southern river otter. The present study confirms the widespread distribution of T. gondii in Southern Chile, and shows a high exposure of semi aquatic mustelids and domestic cats to the parasite. Cats and anthropogenic disturbance have a role in the maintenance of T. gondii infection in ecosystems of southern Chile. These results will be of interest to parasitologists, veterinarians and epidemiologists.

Technical Abstract: The increase in human population and domestic pets, such as cats, are generating important consequences in terms of habitat loss and pathogen pollution of coastal ecosystems with potential to generate negative impacts in marine biodiversity. Toxoplasma gondii is the etiological agent of zoonotic disease toxoplasmosis, and is associated to cat abundance and anthropogenic disturbance. The presence of T. gondii oocysts in the ocean has negatively affected the health status of the threatened Southern sea otter (Enhydra lutris nereis) populations. The present study analyzed seroprevalence (modified agglutination test, MAT, cut-off 1:25) and presence of T. gondii DNA in American mink (Neovison vison), Southern river otters (Lontra provocax) and domestic cats (Felis silvestris catus) in 4 different areas in Patagonia in Southern Chile comprising studies in rivers and lakes in Andean foothills and mountains, marine habitat and island coastal ecosystems. Mean seroprevalence of T. gondii in the study was 64% of 151 total animals sampled: 59% of 73 American mink, 77% of 13 Southern river otters, 68% of 65 domestic cats and in two of two kodkods (Leopardus guigna). T. gondii DNA was detected in tissues from one American mink and one Southern river otter. The present study confirms the widespread distribution of T. gondii in Southern Chile, and shows a high exposure of semiaquatic mustelids and domestic cats to the parasite. Cats and anthropogenic disturbance have a role in the maintenance of T. gondii infection in ecosystems of southern Chile.