Molecular detection of trypanosomatids among cave-dwelling bats from Colombia

Bats play crucial roles in various ecosystems including caves. Although the presence of trypanosomatid species in bats has been documented in Colombia, their diversity in cave-dwelling bats remains unclear. This study aimed to characterize the frequency and diversity of protists from the family Trypanosomatidae circulating in bats from the Macaregua cave ecosystem in Santander, Colombia. A total of 112 specimens from the three permanently residing bat species were examined for trypanosomatid presence through the amplification and sequencing of a region of the 18S rRNA gene in blood samples. We report an overall trypanosomatid detection rate of 42.9% (n = 48), involving the three evaluated bat species: Carollia perspicillata (19/43, 44.2%), Natalus tumidirostris (17/39, 43.6%), and Mormoops megalophylla (12/30, 40.0%). The trypanosomatids were classified by amplicon sequencing and phylogenetic analysis as Trypanosoma spp. (33/112, 29.5%), Leishmania spp. (8/112, 7.1%), and Crithidia spp. (9/112, 8%). In addition, two individuals simultaneously carried more than one genus: Trypanosoma and Leishmania (MT087, C. perspicillata), and Trypanosoma and Crithidia (MT120, M. megalophylla). Some of the samples positive for trypanosomatids were characterized at the species level using the same method with the Cytochrome B gene, identifying Trypanosoma cruzi cruzi (TcI-III and TcBat), Trypanosoma cruzi marinkellei, and Leishmania braziliensis in the evaluated bats. We describe the presence of pathogenic trypanosomatids (T. cruzi cruzi, T. cruzi marinkellei, and L. braziliensis), as well as monoxenous trypanosomatids such as Crithidia spp. as the Trypanosomatidae protists carried by bats in cave ecosystems from Colombia. The discussion on how bats become infected by these parasites and their potential role in wild transmission cycles is provided below.