Reptarenaviruses in Wild- and Captive-Origin Boid and Pythonid Snakes in Peru.

Abstract

Viral pathogens represent an increasing threat to wildlife health and biodiversity. Most studies of reptile viruses are in captive populations, while knowledge of viral occurrence and diversity in free-ranging reptiles is limited. Some reptarenaviruses (family Arenaviridae) are causative agents of boid inclusion body disease (BIBD), an important disease of captive boas and pythons that can be associated with substantial morbidity and mortality in some species. Peru is home to both diverse boid snakes and significant illegal reptile trade. This represents a unique and uninvestigated opportunity for reptarenaviral surveillance to better understand the presence of these viruses in boas in Peru. Oral swabs from 28 individual snakes representing four native boa taxa (Boa constrictor constrictor; the endemic subspecies B. c. ortonii; Epicrates cenchria; and Eunectes murinus), one non-native boa taxon (B. imperator), and two non-native python taxa (Python bivittatus and Python regius) were screened for reptarenaviruses using reverse transcription-PCR and Sanger sequencing. Overall, 64.3% (18/28) of snakes were positive for reptarenaviruses, including 70% (14/20) of wild-origin snakes and 50% (4/8) of captive-origin snakes. Reptarenavirus PCR-positive snakes included both native taxa, including the red-tail boa (Boa constrictor constrictor; 64.3%, 9/14 snakes), Orton's boa (B. c. ortonii; 75%, 3/4 snakes), green anaconda (Eunectes murinus; 100%, 2/2 snakes), and exotic taxa, including the Central American boa (B. imperator; 100%, 2/2 snakes), Burmese python (Python bivittatus; 50%, 1/2 snakes), and ball python (Python regius; 50%, 1/2 snakes). Of the positive snakes, 14 snakes yielded sequences with 99.6-100% nucleotide identity to reference sequences of Reptarenavirus giessenae, one of the best characterized reptarenaviruses documented in association with BIBD. Two additional wild caught red-tail boas yielded reptarenavirus sequences with highest nucleotide identity to unclassified reptarenavirus (S7/S10) strains, and two snakes had mixed chromatograms compatible with amplification of more than one template. These results represent the first molecular confirmation of reptarenaviruses in Peru and suggest that globally significant viruses of captive snakes may be present in wild Peruvian boa populations.