Genetic characterization of a novel G3P[14] rotavirus strain causing gastroenteritis in 12 year old Australian child.

A genotype G3P[14] rotavirus strain was identified in a 12year old child presenting to the Emergency Department of the Royal Children's Hospital, Melbourne, with gastroenteritis. G3P[14] strains have been previously identified in rabbits in Japan, China, the USA and Italy and a single lapine-like strain from a child in Belgium. Full genome sequence analysis of RVA/Human-wt/AUS/RCH272/2012/G3P[14] (RCH272) revealed that the strain contained the novel genome constellation G3-P[14]-I2-R3-C3-M3-A9-N2-T6-E2-H3. The genome was genetically divergent to previously characterized lapine viruses and the genes were distantly related to a range of human bovine-like strains and animal strains of bovine, bat and canine/feline characteristics. The VP4, VP6, NSP2, NSP3, NSP4 and NSP5 genes of RCH272 clustered within bovine lineages in the phylogenetic analysis and shared moderate genetic similarity with an Australian bovine-like human strain RVA/Human-tc/AUS/MG6/1993/G6P[14]. Bayesian coalescent analysis suggested these genes of RCH272 and RVA/Human-tc/AUS/MG6/1993/G6P[14] were derived from a population of relatively homogenous bovine-like ancestral strains circulating between 1943 and 1989. The VP7, VP1, VP2 and NSP1 genes shared moderate genetic similarity with the Chinese strain RVA/Bat-tc/CHN/MSLH14/2011/G3P[3] and the VP3 gene clustered within a lineage comprised of canine and feline strains. This strain may represent the direct transmission from an unknown host species or be derived via multiple reassortment events between strains originating from various species. The patient lived in a household containing domesticated cats and dogs and in close proximity to a colony of Gray-headed Flying-foxes. However, without screening numerous animal populations it is not possible to determine the origins of this strain.