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bioRxiv · 10.1101/2025.05.09.652812

Discovery of a Novel Coltivirus in a Newly Identified Bat Bug Species (Heteroptera: Cimicidae) in Cambodia

Abstract

Bats and their ectoparasites are significant reservoirs and potential vectors of emerging zoonotic pathogens, yet the viral diversity within bat-associated arthropods remains poorly characterized. This study reports the identification of a novel coltivirus (order Reovirales), provisionally designated Stricticimex coltivirus (SCCV), in a newly described bat bug species, Stricticimex phnomsampovensis, collected from cave-dwelling wrinkle-lipped free-tailed bats (Mops plicatus) in Cambodia. Metagenomic sequencing and phylogenetic analysis revealed that SCCV clusters within the Coltivirus genus, showing closest similarity to Tai Forest Reovirus (TFRV) previously isolated from African bats. SCCV was detected in 18.4% of examined bat bugs and successfully isolated in VeroE6 cells, with replication confirmed in multiple mammalian cell lines. The discovery of SCCV extends the known diversity and geographic range of Coltivirus and highlights bat ectoparasites as overlooked hosts of potentially zoonotic viruses. These findings underscore the importance of integrated One Health surveillance targeting both bats and their ectoparasites to better assess the risk of pathogen spillover in biodiverse regions with high human-animal contact. Author SummaryIn this study, we identify a novel Coltivirus, named Stricticimex coltivirus (SCCV), in a newly described bat bug species collected from cave-dwelling bats in Cambodia. Using metagenomic sequencing and phylogenetic analysis, we find that SCCV is closely related to Tai Forest Reovirus, previously identified in African bats. We successfully isolated the virus in mammalian cell lines, suggesting potential to infect vertebrate hosts. This discovery not only expands the known diversity of Coltiviruses, but also underscores the role of bat ectoparasites as underexplored reservoirs of potentially zoonotic viruses. Our findings emphasize the importance of integrated One Health surveillance efforts targeting both bats and their ectoparasites to better assess the risk of virus spillover in regions where human and wildlife habitats overlap.

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BibTeXRIS

Siegers, J. Y., Auerswald, H., Maquart, P.-O., Szentivanyi, T., Guillebaud, J., Hoem, T., Suor, K., Pum, L., Khun, L., Nuon, S., Chea, K., Heang, V., Bienes, K. M., Nouhin, J., Boyer, S., Karlsson, E. A.. 2025-05-09. Discovery of a Novel Coltivirus in a Newly Identified Bat Bug Species (Heteroptera: Cimicidae) in Cambodia. https://doi.org/10.1101/2025.05.09.652812

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