The protozoan parasite Trypanosoma cruzi, is the agent of Chagas' disease, an incurable form of heart disease common in Latin America. Trypanosoma cruzi is usually transmitted to people in Latin America by kissing bugs.
A parasite believed to be T. cruzi is found in wild animals in the United States. Little is known about this indigenous trypanosome, particularly with respect to its ability to cause disease in animals or humans. We have found that this organism infects a high percentage of opossums, raccoons and kissing bugs in Georgia. We also determined that the parasite is morphologically and genetically indistinguishable from strains of T. cruzi others have isolated from infected humans in Latin America, so we are now certain that the Georgia parasite is indeed T. cruzi, not a T. cruzi look-alike. One of my graduate students (Stephanie Pietrzak) discovered that our local strain of the parasite induces mild, probably asymptomatic myocarditis in raccoons. In laboratory mice, the parasite is definitely less pathogenic than its Latin American cousins.
An interesting offshoot of this study is our work with nonhuman primates (ring-tailed lemurs from Madagascar and lion-tailed macaques from India) which were translocated to St. Catherine's Island, Georgia by the Wildlife Conservation Society as part of an endangered species recovery effort. We found that a number of these animals got infected with the Georgia raccoon strain of T. cruzi after arriving on St. Catherine's. We have evidence that the primates infected themselves by eating kissing bugs found on the Island. We hope that our work with this parasite will help to interrupt the cycle of transmission on the island and assist in the assessment of the potential impact of the parasite on these endangered non-human primates.
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