Does Trypanosoma infection affect body condition in bats? A study from Atlantic Forest in southern Bahia, Brazil

Bats harbor a remarkable diversity of trypanosomatids and are key hosts in the evolutionary history of the Trypanosoma cruzi clade. However, the effects of these infections on bat biology remain poorly explored, particularly in human-modified Neotropical landscapes. This study investigated the species diversity of Trypanosoma in bats from a shaded cacao agroforestry system within the Atlantic Forest of southern Bahia, Brazil, and evaluated the association between infection and body condition in Carollia perspicillata, the most abundant species sampled. A total of 153 bats representing 14 species and 2 families were captured, and 135 blood samples were screened by nested PCR targeting 18S rDNA. Twenty-eight individuals (20.7%) tested positive, representing four host species. Sequencing and phylogenetic analyses identified three lineages, Trypanosoma sp. Neobat 1, Trypanosoma sp. Neobat 4, and T. dionisii. These findings represent the first records of these taxa in bats from the state of Bahia, expanding the known geographic distribution of these trypanosomatids. Infection was most frequent in C. perspicillata (22.7%), which also harbored the greatest diversity of Trypanosoma lineages. Infected C. perspicillata exhibited significantly lower body condition than uninfected individuals, indicating that Trypanosoma infection is associated with measurable physiological costs in this host species. Nevertheless, the moderate magnitude of this difference is consistent with a long-term host-parasite association in which chronic infections may persist without overt pathological effects. The occurrence of multiple Trypanosoma lineages in sympatric bat species further highlights the ecological role of bats in maintaining trypanosome diversity within agroforestry landscapes. These results reinforce the importance of integrating bat health metrics with molecular surveillance under a One Health framework to improve our understanding of bat-trypanosome interactions in human-modified ecosystems.