Date of Award
Delfina C. Dominguez
Background: Recognized by the World Health Organization (WHO) as two of the world’s thirteen most neglected tropical diseases (NTD), both T. cruzi and Leishmania spp. parasites are accountable for Chagas disease and Leishmaniasis, respectively and they continue to rank among the most important public health problems in South America. Together, Leishmaniasis and Chagas affect 300 million people. Wildlife reservoirs play an important role in the maintenance and transmission of parasites in sylvatic transmission cycles. In the last decade studies have been conducted in this region of El Paso, Texas, and other parts of the world to detect both parasites in known reservoirs in wild and domestic animals with positive results.
Problem Statement: In the last decade, three studies have been conducted with the intention to identify both these parasites in dogs, cats and sylvatic animals and have provided proof of their presence in this border region and these mentioned species as reservoirs. However, bats have not been studied in this region although they are mammals that migrate every year from South America where bats have been presented as novel reservoirs of Leishmania spp. and known reservoirs for T. cruzi. There are no routine surveillance studies being conducted in the city of El Paso, Tx. to monitor either Leishmaniasis or Chagas disease.
Objectives: The objective of this research is to determine the presence of Leishmania spp. and T. cruzi parasites in the El Paso region by testing the heart, spleen and if dermal lesions observed skin tissue from bats captured in the region.
Method: This study is a cross sectional, observational study collecting tissue samples of wild bats for a period of 5 months. Bats that tested negative for rabies were donated and delivered in conical tubes by TDSHS, Zoonosis Control, Animal Services. Tissue samples were obtained from the heart, spleen and skin of each bat and DNA was extracted then utilizing Polymerase Chain Reaction (PCR) to identify both parasites DNA. PCR content included 12.5 µL of PCR master mix, 1 µL of reverse primer and 1µL of forward primer, 8.5 µL of nuclease free water and 2 µL of DNA template. Primers 121 and 122 were used to amplify 330 bp of the kinetoplast minicircle DNA from T. cruzi. Primers LITSR and L5.8S were used to amplify 320 bp of the ITS1 region for Leishmania spp. DNA. Once PCR was completed, electrophoresis was performed, and bands were visualized with iBrightFL1000 Invitrogen imaging system.
Results: A total of 32 bats were subject of this study, with seven different species observed. Out of 32 bats, 19 (59%) were positive for T. cruzi infection and 5 (16%) tested positive for Leishmania spp. infection.
Conclusion: The city of El Paso, Texas receives each April a cauldron of bats that migrate from south America where bats have been presented as novel reservoirs of Leishmania spp. and are known reservoirs for T. cruzi, they feed, reproduce, and stay all through summer and leave by October. This period may extend due to climate change. This study gives sufficient evidence to add bats as a reservoir for these 2 diseases transmission cycles and to raise concern for more infectious disease epidemiological studies to be performed in our border region as leishmaniasis and Changas disease may no longer be considered only tropical diseases or travelers diseases. May this study serve as a platform to continue research and surveillance both parasites.
Recieved from ProQuest
Sandoval, Edith, "Identification Of Leishmania Spp. And T. Cruzi Parasites In Bats Captured In El Paso, Texas Region: Bats As A New Reserviour" (2021). Open Access Theses & Dissertations. 3347.