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In 2005, natural epizootics were observed during an outbreak of Setothosea asigna (Lepidoptera: Limacodidae) larvae in an oil palm plantation in South Sumatra, Indonesia. The causative agent was filterable, which implied it was a virus. Since preliminary testing using reverse PCA gave a positive result for the Thosea asigna virus (TaV), we experimented with the purification of the viral agent from the diseased larvae. Electron microscopy revealed nonenveloped virus-like particles that were spherical in shape and about 40 nm in diameter. eDNA cloning followed by sequencing demonstrated that RNA purified from the particles contained two large openreading- frames (OAFs) with a partly shared sequence and extensive homology (> 98% identity at the nucleotide level) with OAFs of TaV encoding an RNA-dependent RNA polymerase and the capsid protein, respectively. 3' RACE suggested that there is, like in TaV genomic RNA, no poly(A) tract at the 3'-terminus of the RNA. The pathogenicity of the purified particles against Limacodidae larvae in Japan was demonstrated to be very strong for Monema f/avescens and Austrapoda dentata. These results indicated that the agent causing the epizootic disease among S. asigna larvae in the oil palm plantations was TaV which also has potential as a biological control agent for Limacodidae pests in Japan. [ABSTRACT FROM AUTHOR]

Introduction: The vaccine against SARS-CoV-2 provides humoral immunity to fight COVID-19; however, the acquired immunity gradually declines. Booster vaccination restores reduced humoral immunity; however, its effect on newly emerging variants, such as the Omicron variant, is a concern. As the waves of COVID-19 cases and vaccine programs differ between countries, it is necessary to know the domestic effect of the booster., Methods: Serum samples were obtained from healthcare workers (20-69 years old) in the Pfizer BNT162b2 vaccine program at the Toyama University Hospital 6 months after the second dose (6mA2D, n = 648) and 2 weeks after the third dose (2wA3D, n = 565). The anti-SARS-CoV-2 antibody level was measured, and neutralization against the wild-type and variants (Delta and Omicron) was evaluated using pseudotyped viruses. Data on booster-related events were collected using questionnaires., Results: The median anti-SARS-CoV-2 antibody was >30.9-fold elevated after the booster (6mA2D, 710.0 U/mL [interquartile range (IQR): 443.0-1068.0 U/mL]; 2wA3D, 21927 U/mL [IQR: 15321.0->25000.0 U/mL]). Median neutralizing activity using 100-fold sera against wild-type-, Delta-, and Omicron-derived variants was elevated from 84.6%, 36.2%, and 31.2% at 6mA2D to >99.9%, 99.1%, and 94.6% at 2wA3D, respectively. The anti-SARS-CoV-2 antibody levels were significantly elevated in individuals with fever ≥37.5 °C, general fatigue, and myalgia, local swelling, and local hardness., Conclusion: The booster effect, especially against the Omicron variant, was observed in the Japanese population. These findings contribute to the precise understanding of the efficacy and side effects of the booster and the promotion of vaccine campaigns., (Copyright © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)