Knee osteonecrosis after SARS-CoV-2 infection: a systematic case-based review.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for coronavirus disease 2019 (COVID-19). Patients with COVID-19 manifested symptoms mainly related to the respiratory system, but also the musculoskeletal system can be involved. COVID-19 has been described as a possible cause of knee osteonecrosis (ON). A systematic review was performed to investigate the hypothetical correlation between COVID-19 and knee ON. Methods: Inclusion criteria were all articles reporting cases of knee ON after a diagnosis of SARS-CoV-2 infection. Considering that COVID-19 is an emerging disease, all levels of evidence studies were included. Results: Finally, two case series and three case reports were included. We extracted data regarding demographic and clinical characteristics, details of magnetic resonance imaging (MRI), use of corticosteroids (CCS), temporal correlation between ON and COVID-19, treatment of the lesion and its outcomes. A total of seven cases of post-COVID knee ON have been described. Knee pain arose on average 11 weeks after the diagnosis of COVID-19. All patients had knee MRI showing ON. CCS were used to treat COVID-19-related symptoms in four cases. Conservative treatment was successful in five patients. Conclusions: The correlation between COVID-19 and ON remains unclear. Probably post-COVID-19 ON has a multifactorial origin in which factors related to the patient, consequences of COVID-19 and CCS therapy add up to cause a reduction of blood supply and bone vitality until ON is triggered. A greater number of patients is needed to clarify the role of COVID-19 in the etiopathogenesis of knee ON.

A child with sickle cell disease admitted with coronavirus disease 2019 pneumonia and acute chest syndrome in pediatric intensive care unit: A case report.

Management of sickle cell disease complications in the setting of the coronavirus disease 2019 (COVID-19) pandemic is complicated with little published pediatric data. We report the first documented case of a 9-year-old boy with sickle cell disease, presenting with fever, cough, and shortness of breath, diagnosed to have acute chest syndrome and coronavirus disease 2019 (COVID-19) pneumonia with inflammatory storm requiring ventilation, exchange blood transfusion, immunomodulatory agents, and prophylactic anticoagulation. The patient responded satisfactorily to the management of the acute illness and was found to be well at the next visit to the pediatric hematology outpatient department following hospital discharge.

Neuro-molecular perspectives on long COVID-19 impacted cerebrovascular diseases - a role for dipeptidyl peptidase IV.

The coronavirus disease 2019 (COVID-19) has caused immense devastation globally with many outcomes that are now extending to its long-term sequel called long COVID. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects not only lungs, but also the brain and heart in association with endothelial cell dysfunction, coagulation abnormalities, and thrombosis leading to cardio-cerebrovascular health issues. Fatigue, cognitive decline, and brain fog are common neurological symptoms in persisting long COVID. Neurodegenerative processes and SARS-CoV-2 infection manifest overlapping molecular mechanisms, such as cytokine dysregulation, inflammation, protein aggregation, mitochondrial dysfunction, and oxidative stress. Identifying the key molecules in these processes is of importance for prevention and treatment of this disease. In particular, Dipeptidyl peptidase IV (DPPIV), a multifunctional peptidase has recently drawn attention as a potential co-receptor for SARS-CoV-2 infection and cellular entry. DPPIV is a known co-receptor for some other COVID viruses including MERS-Co-V. DPPIV regulates the immune responses, obesity, glucose metabolism, diabetes, and hypertension that are associated with cerebrovascular manifestations including stroke. DPPIV likely worsens persisting COVID-19 by disrupting inflammatory signaling pathways and the neurovascular system. This review highlights the neurological, cellular and molecular processes concerning long COVID, and DPPIV as a potential key factor contributing to cerebrovascular dysfunctions following SARS-CoV-2 infection.

Human-induced pluripotent stem cell-derived hepatocyte platform in modeling of SARS-CoV-2 infection.

Background and Aim: Currently, SARS-CoV-2 is still spreading rapidly and globally. A large proportion of patients with COVID-19 developed liver injuries. The human-induced pluripotent stem cell (iPSC)-derived hepatocytes recapitulate primary human hepatocytes and have been widely used in studies of liver diseases. Methods: To explore the susceptibility of hepatocytes to SARS-CoV-2, we differentiated iPSCs to functional hepatocytes and tried infecting them with different MOI (1, 0.1, 0.01) of SARS-CoV-2. Results: The iPSC-derived hepatocytes are highly susceptible to virus infection, even at 0.01 MOI. Other than the ancestral strain, iHeps also support the replication of SARS-CoV-2 variants including alpha, beta, theta, and delta. More interestingly, the ACE2 expression significantly upregulated after infection, suggesting a vicious cycle between virus infection and liver injury. Conclusions: The iPSC-derived hepatocytes can support the replication of SARS-CoV-2, and this platform could be used to investigate the SARS-CoV-2 hepatotropism and hepatic pathogenic mechanisms.

Cellular and humoral immunogenicity against SARS-CoV-2 vaccination or infection is associated with the memory phenotype of T- and B-lymphocytes in adult allogeneic hematopoietic cell transplant recipients.

We conducted a cross-sectional study to evaluate cellular and humoral immunogenicity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination or infection and examine how lymphocyte subpopulations in peripheral blood correlate with cellular and humoral immunogenicity in adult allogeneic hematopoietic cell transplantation (HCT) recipients. The median period from SARS-CoV-2 vaccination or infection to sample collection was 110.5 days (range, 6-345 days). The median SARS-CoV-2 spike-specific antibody level was 1761 binding antibody units (BAU)/ml (range, 0 to > 11,360 BAU/ml). Enzyme-linked immunosorbent spot (ELISpot) assay of T cells stimulated with SARS-CoV-2 spike antigens showed that interferon-gamma (IFN-γ)-, interleukin-2 (IL-2)-, and IFN-γ + IL-2-producing T cells were present in 68.9%, 62.0%, and 56.8% of patients, respectively. The antibody level was significantly correlated with frequency of IL-2-producing T cells (P = 0.001) and IFN-γ + IL-2-producing T cells (P = 0.006) but not IFN-γ-producing T cells (P = 0.970). Absolute counts of CD8+ and CD4+ central memory T cells were higher in both IL-2- and IFN-γ + IL-2-producing cellular responders compared with non-responders. These data suggest that cellular and humoral immunogenicity against SARS-CoV-2 vaccination or infection is associated with the memory phenotype of T cells and B cells in adult allogeneic HCT recipients.

Specific sequelae symptoms of COVID-19 of Omicron variant in comparison with non-COVID-19 patients: a retrospective cohort study in Japan.

Background: The specific long-term sequela of coronavirus disease 2019 (COVID-19), also known as long COVID of the Omicron variant remain unclear, due to a lack of cohort studies that include non-COVID patients with cold-like symptoms. The study was conducted to examine specific sequelae symptoms after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, which is considered the Omicron variant, compared with patients who were never-infected. Methods: In this retrospective cohort study, we sent questionnaires in November 2022, targeting those who visited our fever outpatient unit of a single institution from July to September 2022. SARS-CoV-2 infection status was determined by SARS-CoV-2 polymerase chain reaction (PCR) test results during the study period collected in electronic medical records. Clinical characteristics at 30 days or more since the date of SARS-CoV-2 PCR test were assessed by the questionnaires. Multiple logistic regression was performed to investigate the independent association between SARS-CoV-2 infection and possible sequelae symptoms. Results: In total, valid responses were received from 4,779 patients (mean age: 41.4 years, standard deviation: 19.8 years old). Among them, 3,326 (69.6%) and 1,453 (30.4%) were SARS-CoV-2 PCR test positive and never-infected, respectively. We found that patients with SARS-CoV-2 infection were more likely to have a loss of taste or smell [odds ratio (OR) 4.55, 95% confidence interval (CI): 1.93, 10.71], hair loss (OR 3.19, 95% CI: 1.67, 6.09), neurocognitive symptoms (OR 1.95, 95% CI: 1.43, 2.65), and respiratory symptoms (OR 1.23, 95% CI: 1.03, 1.47) than never-infected patients. SARS-CoV-2 infection was not associated with common cold symptoms, chronic physical distress, or diarrhea as sequelae symptoms. Further, SARS-CoV-2 vaccination showed protective effects on sequelae of loss of taste or smell and hair loss. Conclusions: Loss of taste or smell, hair loss, neurocognitive symptoms, and respiratory symptoms were found to be specific sequelae of the SARS-CoV-2 Omicron variant. It is important not to miss these symptoms that follow SARS-CoV-2 infection and to recognize and manage the long COVID.

External Quality Assessment (EQA) for SARS-CoV-2 RNA Point-of-Care Testing in Primary Healthcare Services: Analytical Performance over Seven EQA Cycles.

In April 2020, the Aboriginal and Torres Strait Islander COVID-19 Point-of-Care (POC) Testing Program was initiated to improve access to rapid molecular-based SARS-CoV-2 detection in First Nations communities. At capacity, the program reached 105 health services across Australia. An external review estimated the program contributed to averting between 23,000 and 122,000 COVID-19 infections within 40 days of the first infection in a remote community, equating to cost savings of between AU$337 million and AU$1.8 billion. Essential to the quality management of this program, a customised External Quality Assessment (EQA) program was developed with the Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP). From July 2020 to May 2022, SARS-CoV-2 EQA participation ranged from 93 to 100%. Overall concordance of valid EQA results was high (98%), with improved performance following the first survey. These results are consistent with those reported by 12 Australian and 4 New Zealand laboratories for three SARS-CoV-2 RNA EQA surveys in March 2020, demonstrating that SARS-CoV-2 RNA POC testing in primary care settings can be performed to an equivalent laboratory analytical standard. More broadly, this study highlights the value of quality management practices in real-world testing environments and the benefits of ongoing EQA program participation.

Angiotensin-Converting Enzyme (ACE) Inhibitor-Induced Angioedema in an African American Male With Coronavirus Disease 2019 (COVID-19).

Angioedema is a condition characterized by non-pitting swelling of the subcutaneous or submucosal tissues in particular the face, lips, and oral cavity. Angiotensin-converting enzyme (ACE) inhibitors are known to contribute to the development of angioedema by increasing the levels of bradykinin and its active metabolites. Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is hypothesized to contribute to the development of angioedema by modifying ACE II levels and further increasing the level of bradykinin in patients taking ACE inhibitors. African Americans may be at particular risk of developing angioedema with concomitant SARS-CoV-2 infection and ACE inhibitor use. This case involves a 31-year-old African American male diagnosed with coronavirus disease 2019 (COVID-19) who developed angioedema while taking an ACE inhibitor.

Rapid and Scalable Production of Functional SARS-CoV-2 Virus-like Particles (VLPs) by a Stable HEK293 Cell Pool.

At times of pandemics, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the situation demands rapid development and production timelines of safe and effective vaccines for delivering life-saving medications quickly to patients. Typical biologics production relies on using the lengthy and arduous approach of stable single-cell clones. Here, we used an alternative approach, a stable cell pool that takes only weeks to generate compared to a stable single-cell clone that needs several months to complete. We employed the membrane, envelope, and highly immunogenic spike proteins of SARS-CoV-2 to produce virus-like particles (VLPs) using the HEK293-F cell line as a host system with an economical transfection reagent. The cell pool showed the stability of protein expression for more than one month. We demonstrated that the production of SARS-CoV-2 VLPs using this cell pool was scalable up to a stirred-tank 2 L bioreactor in fed-batch mode. The purified VLPs were properly assembled, and their size was consistent with the authentic virus. Our particles were functional as they specifically entered the cell that naturally expresses ACE-2. Notably, this work reports a practical and cost-effective manufacturing platform for scalable SARS-CoV-2 VLPs production and chromatographic purification.

Association between Dexmedetomidine Use and Mortality in Patients with COVID-19 Receiving Invasive Mechanical Ventilation: A U.S. National COVID Cohort Collaborative (N3C) Study.

(1) Background/Objectives: Dexmedetomidine is a sedative for patients receiving invasive mechanical ventilation (IMV) that previous single-site studies have found to be associated with improved survival in patients with COVID-19. The reported clinical benefits include dampened inflammatory response, reduced respiratory depression, reduced agitation and delirium, improved preservation of responsiveness and arousability, and improved hypoxic pulmonary vasoconstriction and ventilation-perfusion ratio. Whether improved mortality is evident in large, multi-site COVID-19 data is understudied. (2) Methods: The association between dexmedetomidine use and mortality in patients with COVID-19 receiving IMV was assessed. This retrospective multi-center cohort study utilized patient data in the United States from health systems participating in the National COVID Cohort Collaborative (N3C) from 1 January 2020 to 3 November 2022. The primary outcome was 28-day mortality rate from the initiation of IMV. Propensity score matching adjusted for differences between the group with and without dexmedetomidine use. Adjusted hazard ratios (aHRs) for 28-day mortality were calculated using multivariable Cox proportional hazards models with dexmedetomidine use as a time-varying covariate. (3) Results: Among the 16,357,749 patients screened, 3806 patients across 17 health systems met the study criteria. Mortality was lower with dexmedetomidine use (aHR, 0.81; 95% CI, 0.73-0.90; p < 0.001). On subgroup analysis, mortality was lower with earlier dexmedetomidine use-initiated within the median of 3.5 days from the start of IMV-(aHR, 0.67; 95% CI, 0.60-0.76; p < 0.001) as well as use prior to standard, widespread use of dexamethasone for patients on respiratory support (prior to 30 July 2020) (aHR, 0.54; 95% CI, 0.42-0.69; p < 0.001). In a secondary model that was restricted to 576 patients across six health system sites with available PaO2/FiO2 data, mortality was not lower with dexmedetomidine use (aHR 0.95, 95% CI, 0.72-1.25; p = 0.73); however, on subgroup analysis, mortality was lower with dexmedetomidine use initiated earlier than the median dexmedetomidine start time after IMV (aHR, 0.72; 95% CI, 0.53-0.98; p = 0.04) and use prior to 30 July 2020 (aHR, 0.22; 95% CI, 0.06-0.78; p = 0.02). (4) Conclusions: Dexmedetomidine use was associated with reduced mortality in patients with COVID-19 receiving IMV, particularly when initiated earlier, rather than later, during the course of IMV as well as use prior to the standard, widespread usage of dexamethasone during respiratory support. These particular findings might suggest that the associated mortality benefit with dexmedetomidine use is tied to immunomodulation. However, further research including a large randomized controlled trial is warranted to evaluate the potential mortality benefit of DEX use in COVID-19 and evaluate the physiologic changes influenced by DEX that may enhance survival.

Inhibition Mechanism of SARS-CoV-2 Infection by a Cholesterol Derivative, Nat-20(S)-yne.

The coronavirus disease 2019 (COVID-19) is caused by the etiological agent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19, with the recurrent epidemics of new variants of SARS-CoV-2, remains a global public health problem, and new antivirals are still required. Some cholesterol derivatives, such as 25-hydroxycholesterol, are known to have antiviral activity against a wide range of enveloped and non-enveloped viruses, including SARS-CoV-2. At the entry step of SARS-CoV-2 infection, the viral envelope fuses with the host membrane dependent of viral spike (S) glycoproteins. From the screening of cholesterol derivatives, we found a new compound 26,27-dinorcholest-5-en-24-yne-3ß,20-diol (Nat-20(S)-yne) that inhibited the SARS-CoV-2 S protein-dependent membrane fusion in a syncytium formation assay. Nat-20(S)-yne exhibited the inhibitory activities of SARS-CoV-2 pseudovirus entry and intact SARS-CoV-2 infection in a dose-dependent manner. Among the variants of SARS-CoV-2, inhibition of infection by Nat-20(S)-yne was stronger in delta and Wuhan strains, which predominantly invade into cells via fusion at the plasma membrane, than in omicron strains. The interaction between receptor-binding domain of S proteins and host receptor ACE2 was not affected by Nat-20(S)-yne. Unlike 25-hydroxycholesterol, which regulates various steps of cholesterol metabolism, Nat-20(S)-yne inhibited only de novo cholesterol biosynthesis. As a result, plasma membrane cholesterol content was substantially decreased in Nat-20(S)-yne-treated cells, leading to inhibition of SARS-CoV-2 infection. Nat-20(S)-yne having a new mechanism of action may be a potential therapeutic candidate for COVID-19.

Immunohistochemical and Morphometric Analysis of Lung Tissue in Fatal COVID-19.

The primary targets of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the lungs are type I pneumocytes, macrophages, and endothelial cells. We aimed to identify lung cells targeted by SARS-CoV-2 using viral nucleocapsid protein staining and morphometric features on patients with fatal COVID-19. We conducted a retrospective analysis of fifty-one autopsy cases of individuals who tested positive for SARS-CoV-2. Demographic and clinical information were collected from forensic reports, and lung tissue was examined for microscopic lesions and the presence of specific cell types. Half of the evaluated cohort were older than 71 years, and the majority were male (74.5%). In total, 24 patients presented diffuse alveolar damage (DAD), and 50.9% had comorbidities (56.9% obesity, 33.3% hypertension, 15.7% diabetes mellitus). Immunohistochemical analysis showed a similar pattern of infected macrophages, infected type I pneumocytes, and endothelial cells, regardless of the presence of DAD (p > 0.5). The immunohistochemical reactivity score (IRS) was predominantly moderate but without significant differences between patients with and without DAD (p = 0.633 IRS for type I pneumocytes, p = 0.773 IRS for macrophage, and p = 0.737 for IRS endothelium). The nucleus/cytoplasm ratio shows lower values in patients with DAD (median: 0.29 vs. 0.35), but the difference only reaches a tendency for statistical significance (p = 0.083). Our study confirms the presence of infected macrophages, type I pneumocytes, and endothelial cells with a similar pattern in patients with and without diffuse alveolar damage.

The association between probable post-COVID-19 condition and sleep-related parameters: a longitudinal study of non-hospitalised patients.

The long-term effects of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection on sleep remain poorly known. We evaluated the association between probable post-COVID-19 condition and changes in sleep quality and quantity before and after SARS-CoV-2 infection in a consecutive sample of non-hospitalized adults. Individuals were identified with SARS-CoV-2 infection in 2020 at the central laboratory of a tertiary hospital in Porto and followed as outpatients. We included patients diagnosed with SARS-CoV-2 infection ≥3 months before this evaluation, with no missing data on key variables (n = 2445). Participants completed a questionnaire that included sociodemographic, clinical, and infection-related questions. We computed changes in sleep-related parameters referred to 1 month before diagnosis and 1 week before the questionnaire. Multinomial logistic regression models were fitted to compute crude and adjusted odds ratios and 95% confidence intervals (95% CIs). Compared to the pre-infection period, those with probable post-COVID-19 condition reported a greater decrease in hours of sleep, had a 2.60 (95% CI 2.02-3.34) higher adjusted odds of perceiving their sleep quality as worsened and experienced a significant increase in number of days with sleeping disturbances as defined according to multiple items. The association between post-COVID-19 condition and indicators of poor sleep health requires special attention from healthcare professionals and services. It is essential that appropriate multidisciplinary care is provided to mitigate the physical, psychological, social, and professional impact of sleeping problems in these already burdened patients.

Ciclesonide Inhibits SARS-CoV-2 Papain-Like Protease in Vitro.

The emergence of coronavirus disease 2019 (COVID-19), a novel identified pneumonia resulting from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, has significantly impacted and posed significant challenges to human society. The papain-like protease (PLpro) found in the nonstructural protein 3 of SARS-CoV-2 plays a vital role in viral replication. Moreover, PLpro disrupts the host immune response by cleaving ubiquitin and interferon-stimulated gene 15 from host proteins. Consequently, PLpro has emerged as a promising drug target against SARS-CoV-2 infection. Computational studies have reported that ciclesonide can bind to SARS-CoV-2 PLpro. However, the inhibitory effects of ciclenoside on the PLpro have not been experimentally evaluated. Here, we evaluated the inhibitory effects of synthetic glucocorticoids (sGCs), including ciclesonide, on SARS-CoV-2 PLpro in vitro assay. Ciclesonide significantly inhibited the enzymatic activity of PLpro, compared with other sGCs and its IC50 was 18.4 ± 1.89 µM. These findings provide insights into the development of PLpro inhibitors.

Purification of living environments using photocatalysts: Inactivation of microorganisms and decomposition of allergens.

Many emerging and re-emerging infectious diseases are prevalent, and the number of patients with allergies is increasing. Therefore, the importance of purifying the living environment is increasing. Photocatalysts undergo extreme redox reactions and decompose organic matter upon exposure to the excitation light. In contrast to ultraviolet light and disinfectants, which are standard methods for inactivating viruses and eliminating microorganisms, photocatalysts can decompose toxic substances, such as endotoxins and allergens, rendering them harmless to the human body. Photocatalysts have attracted significant attention as potential antiviral and antimicrobial agents. This review outlines the antiviral, antimicrobial, and anti-allergenic effects of photocatalysts. Especially, we have discussed the inactivation of SARS-CoV-2 in liquids and aerosols, elimination of Legionella pneumophila in liquids, decomposition of its endotoxin, decomposition of cat and dog allergens, and elimination of their allergenicity using photocatalysts. Furthermore, we discuss future perspectives on how photocatalysts can purify living environments, and how photocatalytic technology can be applied to companion animals and the livestock industry.

Current Status and Perspectives of Therapeutic Antibodies Targeting the Spike Protein S2 Subunit against SARS-CoV-2.

The global coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has devastated public health and the global economy. New variants are continually emerging because of amino acid mutations within the SARS-CoV-2 spike protein. Existing neutralizing antibodies (nAbs) that target the receptor-binding domain (RBD) within the spike protein have been shown to have reduced neutralizing activity against these variants. In particular, the recently expanding omicron subvariants BQ 1.1 and XBB are resistant to nAbs approved for emergency use by the United States Food and Drug Administration. Therefore, it is essential to develop broad nAbs to combat emerging variants. In contrast to the massive accumulation of mutations within the RBD, the S2 subunit remains highly conserved among variants. Therefore, nAbs targeting the S2 region may provide effective cross-protection against novel SARS-CoV-2 variants. Here, we provide a detailed summary of nAbs targeting the S2 subunit: the fusion peptide, stem helix, and heptad repeats 1 and 2. In addition, we provide prospects to solve problems such as the weak neutralizing potency of nAbs targeting the S2 subunit.

Effects of Hyperbaric Oxygen Therapy on Long COVID: A Systematic Review.

The coronavirus disease (COVID-19) pandemic has resulted in an increasing population that is experiencing a wide range of long-lasting symptoms after recovery from the acute infection. Long COVID refers to this specific condition and is associated with diverse symptoms, such as fatigue, myalgias, dyspnea, headache, cognitive impairment, neurodegenerative symptoms, anxiety, depression, and a sense of despair. The potential of hyperbaric oxygen therapy (HBOT) to improve chronic fatigue, cognitive impairments, and neurological disorders has been established; therefore, the use of HBOT to treat long COVID has also been studied. We conducted a literature search between 1 January 2019 and 30 October 2023, focusing on the clinical efficacy and utility of HBOT for treating long COVID and found ten clinical studies that fit the review topic, including one case report, five one-group pretest-posttest design studies, one safety report from a randomized controlled trial (RCT), and three complete reports of RCTs. Most studies found that HBOT can improve quality of life, fatigue, cognition, neuropsychiatric symptoms, and cardiopulmonary function. Although HBOT has shown some benefits for long COVID symptoms, further rigorous large-scale RCTs are required to establish precise indications, protocols, and post-treatment evaluations.

Virucidal efficacy of hypochlorous acid water for aqueous phase and atomization against SARS-CoV-2.

Coronavirus disease 2019 (COVID-19) is an infectious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that emerged at the end of 2019. SARS-CoV-2 can be transmitted through droplets, aerosols, and fomites. Disinfectants such as alcohol, quaternary ammonium salts, and chlorine-releasing agents, including hypochlorous acid, are used to prevent the spread of SARS-CoV-2 infection. In the present study, we investigated the efficacy of ionless hypochlorous acid water (HOCl) in suspension and by spraying to inactivate SARS-CoV-2. The virucidal efficacy of HOCl solution in tests against SARS-CoV-2 was evaluated as 50% tissue culture infectious dose. Although the presence of organic compounds influenced the virucidal efficacy, HOCl treatment for 20 s was significantly effective to inactivate Wuhan and Delta strains in the suspension test. HOCl atomization for several hours significantly reduced the SARS-CoV-2 attached to plastic plates. These results indicate that HOCl solution with elimination containing NaCl and other ions may have high virucidal efficacy against SARS-CoV-2. This study provides important information about the virucidal efficacy and use of HOCl solution.

Estimating the effective reproduction number of COVID-19 from population-wide wastewater data: An application in Kagawa, Japan.

Although epidemiological surveillance of COVID-19 has been gradually downgraded globally, the transmission of COVID-19 continues. It is critical to quantify the transmission dynamics of COVID-19 using multiple datasets including wastewater virus concentration data. Herein, we propose a comprehensive method for estimating the effective reproduction number using wastewater data. The wastewater virus concentration data, which were collected twice a week, were analyzed using daily COVID-19 incidence data obtained from Takamatsu, Japan between January 2022 and September 2022. We estimated the shedding load distribution (SLD) as a function of time since the date of infection, using a model employing the delay distribution, which is assumed to follow a gamma distribution, multiplied by a scaling factor. We also examined models that accounted for the temporal smoothness of viral load measurement data. The model that smoothed temporal patterns of viral load was the best fit model (WAIC = 2795.8), which yielded a mean estimated distribution of SLD of 3.46 days (95% CrI: 3.01-3.95 days). Using this SLD, we reconstructed the daily incidence, which enabled computation of the effective reproduction number. Using the best fit posterior draws of parameters directly, or as a prior distribution for subsequent analyses, we first used a model that assumed temporal smoothness of viral load concentrations in wastewater, as well as infection counts by date of infection. In the subsequent approach, we examined models that also incorporated weekly reported case counts as a proxy for weekly incidence reporting. Both approaches enabled estimations of the epidemic curve as well as the effective reproduction number from twice-weekly wastewater viral load data. Adding weekly case count data reduced the uncertainty of the effective reproduction number. We conclude that wastewater data are still a valuable source of information for inferring the transmission dynamics of COVID-19, and that inferential performance is enhanced when those data are combined with weekly incidence data.

Clinical characteristics and outcomes of maintenance hemodialysis patients with COVID-19 during the Omicron wave of the pandemic in Beijing: a single center retrospective study.

BACKGROUND: The clinical manifestations and prognosis of hemodialysis patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) during the Omicron wave of the pandemic infection were still unclear. This study investigated the clinical characteristics of patients undergoing maintenance hemodialysis (MHD) infected with it. METHODS: This retrospective single-center study included 151 patients undergoing MHD. Healthcare workers were selected as control group were assessed from December 1, 2022 to March 31, 2023. Clinical data, laboratory test results, treatment protocols, and prognoses were collected and analyzed. RESULTS: The study population included 146 patients with MHD, 93 (63.7%) of whom were infected with SARS-CoV-2. The number of non-severe, severe, and critical cases was 84 (90.3%), 4 (4.3%), and 5 (5.3%), respectively. Six patients (6.5%) died during the study period. The main symptoms of SARS-CoV-2 infection, including fever, cough, and fatigue, were less common in patients with MHD than the controls. During SARS-CoV-2 infection, the C-reactive protein (2.9 vs. 11.8 mg/dl, p < 0.0001) and ferritin levels(257.7 vs. 537 ng/l, p < 0.0001) were elevated. The hemoglobin(113vs 111 g/L, p = 0.0001) and albumin levels(39.4 vs. 36.1 g/L, p < 0.0001) decreased. Generally, it took two months for the hemoglobin levels to recover. Positivity rate for SARS-COV-2 serum immunoglobin G (IgG) antibodies and IgG titers were lower in dialysis patients than the controls. Age was positively associated with disease severity, while age and hyponatremia were associated with death. CONCLUSIONS: Patients with MHD and COVID-19 were primarily classified as non-severe. SARS-CoV-2 infection would soon lead to the increase of inflammation related acute response protein in dialysis patients, and then lead to the decrease of hemoglobin and albumin. About 9.6% in HD patients were severe cases and had poor prognosis. Advanced age and hyponatremia were associated with disease severity and prognosis.