A diarrheic chicken simultaneously co-infected with multiple picornaviruses: Complete genome analysis of avian picornaviruses representing up to six genera.

In this study all currently known chicken picornaviruses including a novel one (chicken phacovirus 1, KT880670) were identified by viral metagenomic and RT-PCR methods from a single specimen of a diarrheic chicken suffering from a total of eight picornavirus co-infections, in Hungary. The complete genomes of six picornaviruses were determined and their genomic and phylogenetic characteristics and UTR RNA structural models analyzed in details. Picornaviruses belonged to genera Sicinivirus (the first complete genome), Gallivirus, Tremovirus, Avisivirus and "Orivirus" (two potential genotypes). In addition, the unassigned phacoviruses were also detected in multiple samples of chickens in the USA. Multiple co-infections promote and facilitate the recombination and evolution of picornaviruses and eventually could contribute to the severity of the diarrhea in chicken, in one of the most important food sources of humans.