In vitro to clinical efficacy: Neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 strains.

Introduction: Neutralizing antibodies have been approved for coronavirus disease 2019 (COVID-19) treatment; however, no study has clarified the link among their neutralizing effect in vitro, the period of infectious virus shedding, and symptoms in the acute phase. Here, we aimed to assess the duration of virus shed and fever in patients with mild COVID-19 stratified by their characteristics and type of neutralizing antibody administered.

Methods: We evaluated the efficacy of neutralizing antibodies in terms of the duration of infectious virus excretion and fever in three groups: patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta strain treated with REGEN-CoV2 (REGN-CoV2 group) and patients infected with Omicron strain treated with S309 (S309 group) or untreated (untreated group).

Virus purification highlights the high susceptibility of SARS-CoV-2 to a chlorine-based disinfectant, chlorous acid.

Chlorous acid water (HClO2) is known for its antimicrobial activity. In this study, we attempted to accurately assess the ability of chlorous acid water to inactivate SARS-CoV-2. When using cell culture supernatants of infected cells as the test virus, the 99% inactivation concentration (IC99) for the SARS-CoV-2 D614G variant, as well as the Delta and Omicron variants, was approximately 10ppm of free chlorine concentration with a reaction time of 10 minutes.

Capture and neutralization of SARS-CoV-2 and influenza virus by algae-derived lectins with high-mannose and core fucose specificities.

We first investigated the interactions between several algae-derived lectins and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We created lectin columns using high-mannose (HM)-type glycan-specific lectins OAA and KAA-1 or core fucose-specific lectin hypninA-2 and conducted binding experiments with SARS-CoV-2. The results showed that these lectins were capable of binding to the virus.

Viable SARS-CoV-2 detected in the air of hospital rooms of patients with COVID-19 with an early infection.

Objectives: This study assessed the concentration of SARS-CoV-2 in the air of hospital rooms occupied by patients with COVID-19 who had viable SARS-CoV-2 in nasopharyngeal (NP) samples in early infection.

Methods: Between July and October 2021, NP swabs were collected from 20 patients with early SARS-CoV-2 infection admitted to a tertiary hospital in Japan. Air samples were collected from their rooms, tested for SARS-CoV-2 RNA, and cultured to determine potential infectivity.

Suppression of SARS-CoV-2 Infection by Existing Kampo Formulas and Crude Constituent Drugs Used for Treatment of Common Cold Respiratory Symptoms.

Several traditional Japanese Kampo formulas are known to have inhibitory effects on infections with viruses that cause respiratory symptoms. Although some herbs and their components have been reported to suppress SARS-CoV-2 replication , it is difficult to compare effective Kampo formulas because of the different methods used in studies. Thus, we carried out experiments on the suppression of SARS-CoV-2 infection by Kampo formulas and crude drugs used for the common cold to compare their suppressive effects on virus infection.

Duration of infectious viral shedding in patients with mild to moderate COVID-19 treated with REGN-CoV2.

Introduction: New treatment methods, such as REGN-CoV2, have been approved for patients with coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the effect of the drug on the duration of infectious viral shedding and viral mutations is unknown. In this study, we investigated the clinical efficacy of REGN-CoV2 treatment in patients with mild to moderate disease and compared its antiviral effects against different strains of SARS-CoV-2.

Ethanol Susceptibility of SARS-CoV-2 and Other Enveloped Viruses.

Ethanol is an effective disinfectant against the novel coronavirus SARS-CoV-2. However, its effective concentration has not been shown, and we therefore analyzed the effects of different concentrations of ethanol on SARS-CoV-2. When SARS-CoV-2 was treated with varying ethanol concentrations and examined for changes in infectivity, the ethanol concentration at which 99% of the infectious titers were reduced was 24.

Duration of infectious virus shedding in patients with severe coronavirus disease 2019 who required mechanical ventilation.

Background: Approximately 5% of patients with coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 develop severe COVID-19. Severe COVID-19 requires respiratory management with mechanical ventilation and an extended period of treatment. Prolonged infectious virus shedding is a concern in severe COVID-19 cases, but few reports have examined the duration of infectious virus shedding.

Effect of intermittent irradiation and fluence-response of 222 nm ultraviolet light on SARS-CoV-2 contamination.

Background: The effectiveness of 222 nm ultraviolet (UV) C light for disinfecting surfaces contaminated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been reported. The aim of this study was to evaluate the effect of the intermittent irradiation of 222 nm UVC on SARS-CoV-2 and the fluence-dependent effect of 222 nm UVC irradiation on SARS-CoV-2 inactivation.

Methods: We experimented with 5 min continuous and intermittent irradiation for 0.

Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has emerged as a serious threat to human health worldwide. Efficient disinfection of surfaces contaminated with SARS-CoV-2 may help prevent its spread. This study aimed to investigate the in vitro efficacy of 222-nm far-ultraviolet light (UVC) on the disinfection of SARS-CoV-2 surface contamination.