Entamoeba and Giardia parasites implicated as hosts of CRESS viruses

Cormac M. Kinsella, Aldert Bart, Martin Deijs, Patricia Broekhuizen, Joanna Kaczorowska, Maarten F. Jebbink, Tom van Gool, Matthew Cotten and Lia van der Hoek

While several studies have discussed or attempted to identify an association between viruses with circular Rep-encoding single-stranded DNA genomes (CRESS viruses) and gut parasites, no CRESS virus was known to infect any protozoan. Metagenomic virus discovery done by Kinsella et al provides the evidence that Entamoeba and Giardia are hosts of CRESS viruses, via networks of viral recombination anchored to specific hosts. This analysis reveals two CRESS virus families (Naryaviridae and Nenyaviridae) infecting Entamoeba parasites, while a third (Vilyaviridae) infects Giardia duodenalis. The trio - named after the after the three rings from Tolkien’s canon - supplements five CRESS virus families already known to infect eukaryotes, extending the CRESS virus host range to protozoa.

Published September 2020 in Nature Communications