Molecular characteristics and zoonotic potential of rotaviruses

Sa？etak Rotaviruses are one of the most important pathogens causing acute gastroenteritis in humans and animals. Among nine species,rotavirus A is particularly emphasised considering its prevalence and pathogenicity. Even today, apart from the substantial morbidityand hospitalisation rates in countries with high hygiene standards, it causes considerable mortality in developing countries. Suchimpact is especially evident if available vaccines are not included in the national immunisation program. Due to the nature of theirgenome, the evolution of rotaviruses is quite rapid owing to the accumulation of point mutations and genome reassortment. Therefore,the high heterogeneity and the fact that nowadays there are 36 G genotypes and 51 P genotypes of rotavirus A, is not surprising.When direct interspecies transmission occurs, rotaviruses are mostly not able to efficiently infect or transmit in the new host. However,genome reassortment can result in the generation of new, potentially emergent, human-animal reassortants. Thus, it is necessaryto continuously monitor the animal rotavirus strains in order to get complete perspective of the potential animal reservoirs thatcould be responsible for the introduction of novel rotaviruses in human population or rotavirus genes in the genetic backbone ofhuman strains. Systematic investigation of rotavirus molecular characteristics in a certain region is of special importance before theintroduction or during the implementation of national immunisation program. Comprehensive research that would evaluate theanimal reservoirs and the zoonotic potential of rotavirus A strains in Croatian ecosystem is currently in progress