Are Human P14 Rotavirus Strains the Result of Interspecies Transmissions from Sheep or Other Ungulates That Belong to the Mammalian Order Artiodactyla ?

A limited number of human G6P14 rotavirus strains that cause gastroenteritis in humans have been isolated in Europe and Australia. The complete genome sequences were determined for five of these human strains--B10925-97 (isolated in Belgium in 1997), 111/05-27 (Italy, 2005), PA169 (Italy, 1987), MG6 (Australia, 1993), and Hun5 (Hungary, 1997)--and their genetic relatedness to animal rotavirus strains was evaluated by sequencing the complete genome of the sheep rotavirus OVR762 (G8P14; Spain, 2002), the guanaco (Lama guanicoe) rotavirus strains Arg/Chubut/99 and Arg/Río Negro/98 (G8P14 and G8P1, respectively; Argentina, 1999 and 1998), the sable antelope strain RC-18/08 (G6P14; South Africa, 2008), and the bovine rotavirus strain Arg/B383/98 (G15P11; Argentina, 1998). These analyses revealed an overall consensus genomic constellation (G6/G8)-P14-I2-(R2/R5)-C2-M2-(A3/A11)-N2-T6-(E2/E12)-H3, together with a few gene reassortments, and the phylogenetic analyses confirmed that the P14 human strains evaluated in this study were closely related to rotavirus strains isolated from sheep, cattle, goats, guanacos, and antelopes and to rabbits (albeit to a lesser extent), suggesting that one (or more) of these animal species might be the source of the human G6P14 strains. The main feature of the genotype and phylogenetic analyses was the close overall genomic relatedness between the five human G6P14 rotavirus strains and the ovine and antelope rotavirus strains. Taken together, these data strongly suggest a common origin for the human P14 strains and those of the even-toed ungulates belonging to the mammalian order Artiodactyla, with sheep probably playing a key role in the interspecies transmission responsible for the introduction of P14 rotavirus strains into the human population.