Detection of an animal-derived G4P[6] group A rotavirus strain in a symptomatic child, in Italy.

During 2017, a G4P[6] group A rotavirus strain was identified in the feces of an Italian child hospitalized for acute gastroenteritis in Southern Italy. Nucleotide sequencing of the 11 genomic segments, revealed the G4-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 genotype constellation. Phylogenetic analyses of the gene segments investigated revealed high nucleotide sequence identities with G4P[6] RVA strains detected previously in pigs and in humans. The human strains related to the Italian G4P[6] were mainly reported from Asia, and were detected after an inter-species transmission event from swine. This study reports the genotyping and phylogenetic analysis of a G4P[6] RVA strain presenting a genomic constellation never detected before in Italy. In addition, this strain was able to cause AGE symptoms in a healthy child, successively hospitalized. The molecular characterization suggested zoonotic origin and inter-species transmission of this strain from swine, living open the possibility of its importation from abroad.