ABSTRACT
Seven outbreaks and four sporadic cases of the non-bacterial gastroenteritis caused by a norovirus (NoV) were detected in Croatia between November 2004 and February 2005. An enzyme immunoassay (EIA) and three different RT-PCRs for the viral polymerase (ORF1 RT-PCR) and genogroup I (GI) or II (GII) of capsid gene regions (GI-ORF2 RT-PCR; GII-ORF2 RT-PCR) were performed to detect NoV in 21 stool samples. To characterize NoVs, sequencing of the ORF1 region was performed on 12 RT-PCR positive samples, whereas the ORF2 region was sequenced for 5 cases. Four outbreaks were caused by the genotype GII.4 (Lordsdale) and one outbreak was caused by the genotype GI.1 (Norwalk). One of the outbreaks was characterized as potentially mixed GII.4 and GI.1 infection. In the monitored period, genotype GII.4 dominated as the cause of noroviral infections in adults.
