First Record of Amblyomma fuscum (Acari: Ixodidae) on a Nine-Banded Armadillo (Dasypus novemcinctus) with Simultaneous Detection of Medically Important Pathogens: a case report

Abstract The nine-banded armadillo (Dasypus novemcinctus) is a widely distributed wild mammal recognized as a reservoir for zoonotic pathogens like Mycobacterium leprae and Trypanosoma cruzi. This study reports the first record of the rare tick Amblyomma fuscum, a species historically associated with reptilian hosts, parasitizing a D. novemcinctus in Pelotas, Rio Grande do Sul, Brazil, detected through opportunistic sampling of a road-killed specimen. During necropsy, spleen, heart, liver, and blood samples were collected, and total genomic DNA was extracted using the TRIzol® method, which involves phenol–guanidine isothiocyanate-based cell lysis, chloroform phase separation, and ethanol DNA precipitation. PCR assays targeting the Mycobacterium spp., Rickettsia spp. and T. cruzi were performed on spleen tissue, confirming the presence of Mycobacterium spp. and T. cruzi. The tick was tested for Rickettsia spp., Spotted Fever Group Rickettsia spp., Mycobacterium leprae, Babesia spp., Borrelia spp. and B. burgdorferi, Theileria sp., Anaplasma phagocytophilum, and Ehrlichia spp., with M. leprae being the only detected pathogen. This finding expands the known host range of A. fuscum to mammals, challenging the hypothesis of its strict specificity to reptiles, and underscores the epidemiological relevance of D. novemcinctus as a sentinel species. The simultaneous detection of zoonotic agents in both host and ectoparasite highlights the value of systematic monitoring of road-killed fauna for understanding host–parasite–pathogen interactions and assessing public health risks at the wildlife–human interface.