Novel avian calicivirus genome with type IV internal ribosomal entry site (IRES) in black-headed gull (Chroicocephalus ridibundus) in Hungary.

In this study, a taxonomically novel avian calicivirus detected and characterized by next generation sequencing, RT-PCR and Sanger sequencing methods in faecal specimen collected from black-headed gull (Chroicocephalus ridibundus) in Hungary. The complete genome length of the calicivirus strain gull/HA15097/HUN/2018 (PZ810127) is remarkably long, 8,845 nucleotides, which had type IV internal ribosomal entry site (IRES) at the 5', and a stem-loop-II-like (s2m) sequence motif at the 3' untranslated regions. The VP1 capsid protein had less than 26% aa identity to the members of the known calicivirus genera. Caliciviruses appear to be widespread not only in mammals including humans but also in various bird species.