ABSTRACT
BACKGROUND: Disinfection is one of the most effective ways to block the rapid transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Due to the prolonged coronavirus disease 2019 (COVID-19) pandemic, disinfectants have become crucial to prevent person-to-person transmission and decontaminate hands, clothes, facilities and equipment. However, there is a lack of accurate information on the virucidal activity of commercial disinfectants. AIM: To evaluate the virucidal efficacy of 72 commercially available disinfectants constituting 16 types of ingredients against SARS-CoV-2. METHODS: SARS-CoV-2 was tested with various concentrations of disinfectants at indicated exposure time points as recommended by the manufacturers. The 50% tissue culture infectious dose assay was used to calculate virus titre, and trypan blue staining and CCK-8 were used to assess cell viability after 3-5 days of SARS-CoV-2 infection. FINDINGS: This study found that disinfectants based on 83% ethanol, 60% propanol/ethanol, 0.00108-0.0011% sodium dichloroisocyanurate and 0.497% potassium peroxymonosulfate inactivated SARS-CoV-2 effectively and safely. Although disinfectants based on 0.05-0.4% benzalkonium chloride (BAC), 0.02-0.07% quaternary ammonium compound (QAC; 1:1), 0.4% BAC/didecyldimethylammonium chloride (DDAC), 0.28% benzethonium chloride concentrate/2-propanol, 0.0205-0.14% DDAC/polyhexamethylene biguanide hydrochloride (PHMB) and 0.5% hydrogen peroxide inactivated SARS-CoV-2 effectively, they exhibited cytotoxicity. Conversely, disinfectants based on 0.04-4% QAC (2:3), 0.00625% BAC/DDAC/PHMB, and 0.0205-0.14% and 0.0173% peracetic acid showed approximately 50% virucidal efficacy with no cytotoxicity. Citric acid (0.4%) did not inactivate SARS-CoV-2. CONCLUSION: These results indicate that most commercially available disinfectants exert a disinfectant effect against SARS-CoV-2. However, re-evaluation of the effective concentration and exposure time of certain disinfectants is needed, especially citric acid and peracetic acid.
ABSTRACT
Detailed, accurate data related to a disease outbreak enable informed public health decision making. Given the variety of data types available across different regions, global data curation and standardization efforts are essential to guarantee rapid data integration and dissemination in times of a pandemic.
ABSTRACT
Background: Liver transplantation (LT) activities during the COVID-19 pandemic have been curtailed in many countries which has led to increased percentage of waitlist deaths. The impact of various policies restricting LT on outcomes of patients on the LT waitlist is unclear. This study aims to model effects of various scenarios and duration of LT disruption on outcomes. Methods: Using nationwide data from Hong Kong and Singapore of 571 patients between January 2016 and May 2020, we utilized a continuous time Markov chains model approach to evaluate the three following outcomes: (a) overall survival, (b) proportion of waitlist dropout in HCC patients, and (c) proportion of patients that developed acuteon-chronic liver failure (ACLF) while on the LT waitlist under the five scenarios. The five scenarios were: (1) no limitation to LT (both deceased donor liver transplant [DDLT] and living donor liver transplant [LDLT]), (2) no limitation to DDLT, only urgent (acute liver failure [ALF] or ACLF) LDLT allowed, (3) only urgent LT (DDLT and LDLT) allowed, (4) only DDLT, no LDLT allowed and (5) complete cessation of LT. For each scenario, varying periods of 1-, 3-, 6- and 12-month duration of disruption were simulated. Results: With complete cessation of LT, the projected 1-year overall survival (OS) decreased by 3.6%, 10.51% and 19.21% for a 1-, 3- and 6-month disruption respectively when compared to no limitation to LT, while 5-year OS decreased by 5.3%, 15.81%, and 31.11% respectively. When only urgent LT was allowed, the projected 1-year OS decreased by a similar proportion: 3.1%, 8.41% and 15.20% respectively. When only DDLT was allowed to take place, the 1-year projected OS decreased by a smaller proportion - 1.9%, 6.30% and 10.79% for a 1-, 3-, 6-month disruption respectively. When DDLT and only urgent LDLT were allowed, 1-year projected OS was similar to when only DDLT was allowed, at 1.2%, 5.1% and 8.85% for a 1-, 3- and 6-month disruption respectively (Figure 1A). Complete cessation of LT activities resulted in an increased projected incidence of ACLF at 1-year by 17.6%, 49.1% and 95.5%, as well as an increase in hepatocellular carcinoma (HCC) dropout resulting in delisting at 1-year by 31.8%, 107.96% and 176.06% for a 1-, 3- and 6- month disruption respectively (Figure 1B). When only urgent LT was allowed, HCC dropout and ACLF incidence were comparable to the rates seen in the scenario of complete LT cessation. Conclusion: A short and wide-ranging disruption to LT results in better outcomes compared with a longer duration of partial restrictions. Findings from our study provide useful guidance for LT units worldwide in navigating the peaks and troughs of COVID-19 surges and highlight the impact of LT disruption on waitlisted patients during this prolonged pandemic. Once the peak of the COVID-19 wave has passed, DDLT at minimum should be resumed as soon as possible.
ABSTRACT
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a global health concern. Various SARS-CoV-2 vaccines have been developed and are being used for vaccination worldwide. However, no therapeutic agents against coronavirus disease 2019 (COVID-19) have been developed so far;therefore, new therapeutic agents are urgently needed. In the present study, we evaluated several hepatitis C virus direct-acting antivirals as potential candidates for drug repurposing against COVID-19. Theses include asunaprevir (a protease inhibitor), daclatasvir (an NS5A inhibitor), and sofosbuvir (an RNA polymerase inhibitor). We found that asunaprevir, but not sofosbuvir and daclatasvir, markedly inhibited SARS-CoV-2-induced cytopathic effects in Vero E6 cells. Both RNA and protein levels of SARS-CoV-2 were significantly decreased by treatment with asunaprevir. Moreover, asunaprevir profoundly decreased virion release from SARS-CoV-2-infected cells. A pseudoparticle entry assay revealed that asunaprevir blocked SARS-CoV-2 infection at the binding step of the viral life cycle. Furthermore, asunaprevir inhibited SARS-CoV-2 propagation in human lung Calu-3 cells. Collectively, we found that asunaprevir displays broad-spectrum antiviral activity and therefore might be worth developing as a new drug repurposing candidate for COVID-19.