Submitted to: Journal of Parasitology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/1/2010
Publication Date: 5/1/2011
Citation: Houk, A.E., Goodwin, D.G., Zajac, A.M., Barr, S.C., Dubey, J.P., Lindsay, D.S. 2011. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozonn cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossum, Didelphis virginiana, from Southern Louisian. Journal of Parasitology. 96:1119-1122. 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 undercooked meat from infected animals and food and water contaminated with oocysts. In the present study scientists document seroprevalences of Toxoplasma in and other related zoonotic parasites in opossums from Louisiana. The results will be of interest to biologists, parasitologists, and veterinarians.
Technical Abstract: We examined the prevalence of antibodies to zoonotic protozoan parasites (Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoan’s of veterinary importance (Neospora caninum, Sarcocystis neurona and Besnoitia darlingi) in a population of North American opossums (Didelphis virginiana) from Louisiana. Samples from 30 opossums were collected as part of a survey for T. cruzi in Louisiana opossums. Frozen sera from these 30 opossums were examined using an indirect immunofluorescent antibody test (IFAT) against in vitro produced antigenic stages of these protozoans. Additionally, 24 of the 30 samples were examined using haemoculture and all 30 were examined in the modified direct agglutination test (MAT) for antibodies to To. gondii. The prevalence of reactive IFAT samples were as follows: 60% for T. cruzi, 27% for To. gondii, 23% for E. cuniculi, 17% for S. neurona, 47% for B. darlingi, and 0% for N. caninum. Hemaculture revealed that 16 (67%) of 24 samples were positive for T. cruzi compared to 18 of 30 (60%) by IFAT. The sensitivity and specificity for the IFAT compared to hemaculture was 100% for each. The modified direct agglutination test revealed that 9 (30%) the 30 samples from opossums had antibodies to T. gondii compared to 8 (27%) using the IFAT. The sensitivity and specificity of the IFAT compared to the MAT was 100% and 72%, respectively.