Trypanosoma cruzi and Leishmania spp. in rodents in a peri-urban area of Central Mexico.

Rodents are one of the most relevant groups of mammals involved in the process of zoonotic disease transmission. Their ability to adapt to anthropized environments allows them to come into contact with humans with often negative consequences for the latter. The present study designed to detect the presence of Trypanosoma cruzi and Leishmania spp. in rodents living in the peri-urban area of Queretaro in central Mexico. This research was carried out during two seasons of collection of wild and domestic rodents, in three localities within the peri-urban area of the state of Queretaro. These collections were carried out during the dry season of February-May 2017 and in the rainy season of August-November 2017. Samples were obtained from the tail tip, from which DNA was purified using the DNeasy Blood & Tissue Kit. End-point PCR was used for the identification of Trypanosoma cruzi and Leishmania spp. A total of 82 rodents were caught, represented in three families, six genera and seven species, of which 29 (35.3%) were positive for Trypanosoma cruzi; 13 (15.8%) for Leishmania spp.; and 12 individuals presented co-infection with both parasites (14.6%). This study confirmed the presence of Trypanosoma cruzi and Leishmania spp. in synanthropic rodents in the peri-urban area of Queretaro, where Chagas and Leishmaniosis diseases are not considered endemic. It is necessary to continue researching for the presence of vectors, as well as for the detection of diseases caused by parasites in humans and thus be able to confirm the transmission cycle of Trypanosoma cruzi and Leishmania spp. in this central Mexican city.

Gray fox (Urocyon cinereoargenteus) parasite diversity in central Mexico.

Mexico has a long history of parasitological studies in communities of vertebrates. However, the mega diversity of the country makes fauna inventories an ongoing priority. Presently, there is little published on the parasite fauna of gray foxes (Urocyon cinereoargenteus Schereber, 1775) and this study provides new records of parasites for gray foxes in central Mexico. It is a continuation of a series of previous parasitological studies conducted with this carnivore in Mexico from 2003 to the present. A total of 24 foxes in the Parque Nacional El Cimatario (PANEC) were trapped, anaesthetized, and parasites recovered. The species found were Dirofilaria immitis, Ctenocephalides canis, C. felis, Euhoplopsillus glacialis affinis (first report for gray foxes in Mexico) Pulex simulants, and Ixodes sp. Three additional gray fox carcasses were necropsied and the parasites collected were adult nematodes Physaloptera praeputialis and Toxocara canis. The intensive study of the gray fox population selected for the 2013-2015 recent period allowed for a two-fold increase in the number of parasite species recorded for this carnivore since 2003 (nine to 18 parasite species), mainly recording parasitic arthropods, Dirofilaria immitis filariae and adult nematodes. The parasite species recorded are generalists that can survive in anthropic environments; which is characteristic of the present ecological scenario in central Mexico. The close proximity of the PANEC to the city of Santiago de Queretaro suggests possible parasite transmission between the foxes and domestic and feral dogs. Furthermore, packs of feral dogs in the PANEC might have altered habitat use by foxes, with possible impacts on transmission.

Presence of trypanosomatid antibodies in gray foxes (Urocyon cinereoargenteus) and domestic and feral dogs (Canis lupus familiaris) in Queretaro, Mexico.

Trypanosoma cruzi and Leishmania spp. are vector-borne parasitic protozoa, the causative agents of Chagas and Leishmaniasis diseases, respectively. Trypanosoma cruzi and Leishmania spp. have been reported in a wide variety of mammals, including canids, which play an important role in the transmission of these parasites between urban and natural environments. Currently, no studies have been conducted on trypanosomatids in wild canids in Mexico. Using a partially purified fraction of excreted Iron Superoxide dismutase (FeSODe) of T. cruzi, L. mexicana, and L. infantum as antigen for the ELISA and Western blot tests, we detected the presence of antibodies against these parasites in gray foxes (Urocyon cinereoargenteus Schreber, 1775), domestic and feral dogs (Canis lupus familiaris L.) from Queretaro. Our study provides new information regarding the potential of these carnivores as reservoirs of T. cruzi, Leishmania mexicana, and L. infantum for Latin America.