G-genotyping of rotaviruses in stool samples in Salento, Italy


Rotaviruses are the most common agents of diarrhoeal illnessin infants and young children. Gastroenteritis caused byrotaviruses is also more likely to be associated with severe dehydration compared to other viral gastroenteritis.We determined the G-genotype of rotaviruses circulating in theSalento. During 2004, 144 stool samples were collected fromsubjects with a positive screening test and stored at -20 °C untilconfirmation could take place using molecular biology techniques. A reverse transcription-polymerase chain reaction (RTPCR) assay for the amplification of gene VP7 of rotavirus wasdeveloped and used; G-genotype was determined by sequencing and phylogenetic analysis. A total of 101 stool samples were detected positive by RT-PCRand 35 were sequence analyzed and classified into G1, G2, G4,G9 and G12 type. The overall relative incidence of G-types inSalento is different to that of other developed countries. Themost prevalent genotype was G2 while genotype G1 was present at low levels. It is also interesting to note the presence ofG9 rotavirus, which is now recognized as the fifth globallyimportant rotavirus genotype.In this study, therefore, we demonstrate the usefulness of a simple method for correctly determining the G genotypes circulating in a geographic region.