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Previously, we explored the epidemic pattern and molecular characterization of noroviruses (NoVs) isolated in Chungnam, Korea in 2008, and the present study extended these observations to 2009 and 2010. In Korea, NoVs showed the seasonal prevalence from late fall to spring, and widely detected in preschool children and peoples over 60 years of age. Epidemiological pattern of NoV was similar in 2008 and in 2010, but pattern in 2009 was affected by pandemic influenza A/H1N1 2009 virus. NoV-positive samples were subjected to sequence determination of the capsid gene region, which resolved the isolated NoVs into five GI (2, 6, 7, 9 and 10) and eleven GII genotypes (1, 2, 3, 4, 6, 7, 8, 12, 13, 16 and 17). The most prevalent genotype was GII.4 and occupied 130 out of 211 NoV isolates (61.6%). Comparison of NoV GII.4 of prevalent genotype in these periods with reference strains of the same genotype was conducted to genetic analysis by a phylogenetic tree. The NoV GII.4 strains were segregated into seven distinct genetic groups, which are supported by high bootstrap values and previously reported clusters. All Korean NoV GII.4 strains belonged to either VI cluster or VII cluster. The divergence of nucleotide sequences within VI and VII intra-clusters was > 3.9% and > 3.5%, respectively. The "Chungnam(06-117)/2010" strain which was isolated in June 2010 was a variant that did not belong to cluster VI or VII and showed 5.8-8.2%, 6.2-8.1% nucleotide divergence with cluster VI and VII, respectively.

Background Enterovirus 71 (EV71) is a major causative agent of hand-foot-mouth disease (HFMD) and also causes severe neurological complications, leading to fatality in young children. However, no effective therapy is currently available for the treatment of this infection. Methods We identified small-molecule inhibitors of EV71 from a screen of 968 Food and Drug Administration (FDA)-approved drugs, with which clinical application for EV71-associated diseases would be more feasible, using EV71 subgenomic replicon system. Primary hits were extensively evaluated for their antiviral activities in EV71-infected cells. Results We identified micafungin, an echinocandin antifungal drug, as a novel inhibitor of EV71. Micafungin potently inhibits the proliferation of EV71 as well as the replication of EV71 replicon in cells with a low micromolar IC50 (~5 μM). The strong antiviral effect of micafungin on EV71 replicon and the result from time-of-addition experiment demonstrated a targeting of micafungin on virion-independent intracellular process(es) during EV71 infection. Moreover, an extensive analysis excluded the involvement of 2C and 3A proteins, IRES-dependent translation, and also that of polyprotein processing in the antiviral effect of micafungin. Conclusions Our research revealed a new indication of micafungin as an effective inhibitor of EV71, which is the first case reporting antiviral activity of micafungin, an antifungal drug. Electronic supplementary material The online version of this article (doi:10.1186/s12985-016-0557-8) contains supplementary material, which is available to authorized users.