[Molecular epidemiology of rotaviruses in preschool children].

Numerous epidemiological studies, conducted in both developed and developing countries, have shown that the rotavirus is an important aetiological agent in severe diarrhoeal diseases among preschool children. In recent years, different biochemical techniques for the genetic and phenotypic analysis of rotaviruses have been developed. The aim of this study was to define the biological and genetic differences among rotaviruses isolated from the faeces of affected children, by using the Polyacrylamide Gel Electrophoresis technique, as well as to type the viruses and establish the number of strains circulating within our population. In total, 124 faeces samples from children up to 5 years of age were analysed. With the use of the ELISA test, rotaviruses were isolated in 10.3% of cases. The extraction of viral RNA was carried out directly from the faeces samples, which was followed by electrophoresis, and finally observation using a UV lamp, and documentation with a photo camera. The analysis of viral RNA, using Polyacrylamide Gel Electrophoresis (PAGE), revealed equal mobility in all segments of the genome. The results of our analysis demonstrated that the same strains of rotaviruses do circulate within our population. Such a result can be explained as a consequence of our years-long isolation as well as of the decreased mobility of our population. However, the results do not signify that the rotavirus genome in this region will not be susceptible to variations and that, consequently, new strains will not be created.