Seroepidemiological evidence of severe fever with thrombocytopenia syndrome virus infections in wild boars in Nagasaki, Japan

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease in East Asia. It is thought that the SFTS virus (SFTSV) circulates between ticks and animals in nature and that the virus is transmitted to humans by tick bites. SFTS is endemic to Nagasaki in western Japan; however, epidemiological information regarding SFTSV in Nagasaki is not known. In this study, we performed SFTSV IgG ELISAs and neutralization antibody assays for a seroepidemiological survey using samples from wild boars captured in six areas of Nagasaki. SFTSV seropositive animals were found in three areas. Our findings provide epidemiological information on the distribution of SFTSV in Nagasaki

Identification of novel antiviral of fungus-derived brefeldin A against dengue viruses

Microbial natural products possess a wide range of biological and biochemical potential. Among them, fungal secondary metabolites are one of the most important sources for discovering new drugs or lead compounds. In the present study, we explored substances produced by the strain Penicillium sp. FKI-7127 for its antiviral activity. We identified brefeldin A as a novel antiviral agent against dengue viruses. The inhibitory effect of brefeldin A was confirmed by virus titer and immunofluorescence assay. Brefeldin A inhibited dengue viruses regardless of serotypes and other related viruses including Zika virus and Japanese encephalitis virus. Time-of-addition study showed that brefeldin A exerts its antiviral effect at an early stage of the dengue virus (DENV) life cycle. These studies demonstrate that (i) brefeldin A could be used as a lead compound for drug development of anti-DENV and other related viruses and (ii) fungal metabolites are a potential and valuable source for dengue virus drug discovery

Development of a Reverse Transcription-Loop-Mediated Isothermal Amplification Assay for Detection of Pandemic (H1N1) 2009 Virus as a Novel Molecular Method for Diagnosis of Pandemic Influenza in Resource-Limited Settings▿

This paper reports on the development of a one-step, real-time reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay targeting the hemagglutinin (HA) gene for the rapid molecular-based detection of pandemic (H1N1) 2009 virus. The detection limit of the pandemic (H1N1) 2009 virus HA-specific RT-LAMP assay was same as that of the currently used real-time reverse transcription-PCR method. The assay detected the pandemic (H1N1) 2009 virus HA gene in 136 RNA samples extracted from nasopharyngeal swab specimens from Japanese and Vietnamese patients. No cross-reactive amplification with the RNA of other seasonal influenza viruses was observed, and the detection of specific viral genome targets in clinical specimens was achieved in less than 40 min. The sensitivity and specificity of the pandemic (H1N1) 2009 virus HA-specific RT-LAMP assay obtained in this study were 97.8% and 100%, respectively. Use of the (H1N1) 2009 virus HA-specific RT-LAMP assay will enable the faster and easier diagnosis of pandemic (H1N1) 2009 virus infection, especially in resource-limited situations in developing countries