Two Avastrovirus Species Discovered in Psittaciformes Expand the Host Range of the Family Astroviridae.

Metatranscriptomics has recently revealed greater species richness and host range of the Avastrovirus genus, quadrupling the number of avian orders known to host them in less than a decade. Despite this growing awareness of astrovirus presence in wild birds, limited attention has been paid to these viruses in the context of disease in Australian avifauna. Here we used unbiased RNA sequencing of intestinal samples from a galah (Eolophus roseicapilla) and an Australian king parrot (Alisterus scapularis) with a chronic diarrhoeal and wasting disease to detect the entire genomes of two novel astrovirus species. We propose naming these viruses Avastrovirus eolorosei (PQ893528) and Avastrovirus aliscap (PQ893527). The phylogenetic positions of these viruses highlight the importance of current and future metatranscriptomic virus screening in investigations of avian host landscapes beyond Galloanserae. This is also the first documentation of avastrovirus infections in Psittaciformes and the first to report their potential role as disease agents in them.