Molecular epidemiology of human rotavirus infections.

Recognition of rotaviruses as a major aetiological agent of acute gastroenteritis in infants and young children has prompted the investigation of their epidemiology by molecular techniques. Genome analysis by electrophoretic separation of the RNA segments has been widely used to distinguish virus isolates and to monitor patterns of virus transmission. Examination of virus isolates from different epidemics has clearly demonstrated the existance of extensive genomic variation in viruses circulating in large communities; with the co-circulation of a number of viruses of differing electrophoretype. Preliminary studies using the more advanced techniques of oligonucleotide mapping and hybridization analysis have suggested that variation among the viruses may occur by processes involving both "drift" and "shift". Because of their ease and specificity the new hybridization analysis techniques should greatly facilitate both the rapid diagnosis of rotavirus infections, and the solution of many epidemiological and evolutionary questions. Continued and expanded use of molecular techniques for the study of the epidemiology of rotavirus infections will be required to manage future outbreaks and to effect long term control measures.