Human and bovine serotype G 8 rotaviruses may be derived by reassortment

The origin of, and relationship between human and bovine serotype G 8 rotaviruses were investigated by genomic hybridisation. Radiolabelled mRNAs of human G 8 rotaviruses 69 M (isolated in Indonesia) and HAL 1271 (isolated in Finland), and bovine rotaviruses KK 3 (G 10) and NCDV (G 6), were used as probes. The products of liquid hybridisation between the probes and the genomic RNA of human and bovine rotaviruses, including bovine G 8 rotavirus 678 (isolated in Scotland) and two other Finnish human G 8 rotaviruses HAL 1166 and HAL 8590, were examined by separation in polyacrylamide gels. The genomes of Finnish human G 8 rotaviruses were similar to those of bovine G 6 and G 10 rotaviruses. Neither Indonesian human G 8 nor bovine G 8 viruses had high levels of similarity to each other or to other bovine and human rotaviruses. Thus these three epidemiologically distinct G 8 rotaviruses have different origins and may be derived by reassortment with rotaviruses of a third, as yet unknown, host species. The similarity between the Finnish isolates and the bovine isolate NCDV suggests that they have diverged recently and that these human G 8 rotaviruses may be derived from a zoonotic infection, or alternatively, from the live rotavirus vaccine of bovine origin which has been used to vaccinate Finnish children.