An overview on the treatments and prevention against COVID-19

Comparative Analysis of Neuropsychiatric Adverse Reactions Associated with Remdesivir and Nirmatrelvir/Ritonavir in COVID-19 Treatment: Insights from EudraVigilance Data

Remdesivir (RDV) and nirmatrelvir/ritonavir (NMVr) are among the most widely used antivirals in the treatment of COVID-19, aiming to reduce disease severity and progression. Adverse neuropsychiatric effects, such as anxiety, sleep disturbances, and movement disorders, have emerged as significant concerns associated with these treatments. To better understand the safety profiles of RDV and NMVr, this study performs a pharmacovigilance analysis of individual case safety reports (ICSRs) from the EudraVigilance (EV) database. Objectives: This study evaluates the risk of neuropsychiatric adverse events associated with RDV and NMVr. Comparisons with other antiviral drugs, including darunavir, sofosbuvir, ribavirin, tenofovir, ritonavir, and sotrovimab, are also performed to develop a comprehensive understanding of the safety profiles. Methods: A retrospective analysis of ICSRs submitted to EV until 7 July 2024, with data extraction on 12 July 2024, was conducted. Demographic characteristics (age, sex, geographic region, and reporter type) and case severity were included in the descriptive analysis. Disproportionality analysis using reporting odds ratio (ROR) and 95% confidence intervals (CI) was performed to compare adverse drug reaction (ADRs) frequencies across 27 system organ classes (SOCs), with emphasis on "Nervous system disorders" and "Psychiatric disorders. Results: The total number of ICSRs was significantly higher for NMVr (n = 8078) compared to RDV (n = 3934). Nervous system disorders accounted for 3.07% of the total RDV reports and for 17.31% of NMVr reports, while psychiatric disorders represented 0.92% of the total ADRs reported for RDV (n = 60) and 3.61% for NMVr (n = 672). On the other hand, RDV showed a significantly lower frequency of reporting headache compared to NMVr (ROR: 0.1057; 95% CI: 0.0676-0.1653). Conclusions: NMVr presents a higher risk of neuropsychiatric ADRs than RDV, underscoring the need for enhanced monitoring, particularly in patients with preexisting central nervous system (CNS) conditions. These findings contribute to optimizing antiviral safety and informing clinical decision making.

A tale of two drugs: Molnupiravir and Paxlovid

The orally administered antiviral drug Lagevrio or molnupiravir (MOV) and the combination antiviral drug nirmatrelvir/ritonavir or Paxlovid (PAX) have been shown to reduce the likelihood of hospitalization and death for high-risk patients with COVID-19. Clinical studies, including those comparing PAX and MOV, were reviewed; both drugs are effective in reducing morbidity and mortality in COVID patients, although PAX generally appears to be more efficacious. Both drugs received Emergency Use Authorization in the United States for mild to moderate COVID-19 infection, while only PAX has subsequently been given full FDA approval. The principal disadvantage of PAX is that it interacts with many commonly used drugs, while MOV does not. The purpose of this review is to summarize current information and knowledge about these two drugs. The two drugs have completely different mechanisms of action. PAX inhibits viral replication while MOV induces viral replication errors that are expected to lead to viral inactivation. There is, however, the potential that MOV also could mutate host DNA and cause the virus to mutate into variants with new features. The package insert for MOV states that patients should be notified of relevant toxicity issues before administration. Sensitive mutation detection/analysis studies, such as error corrected Next Generation Sequencing (ecNGS) or HPRT mutation detection assays, in MOV-treated patients are needed to establish the safety of MOV.

Treatment with the CCR5 antagonist OB-002 reduces lung pathology, but does not prevent disease in a Syrian hamster model of SARS-CoV-2 infection

Since the emergence of SARS-CoV-2 and the COVID-19 pandemic, a wide range of treatment options have been evaluated in preclinical studies and clinical trials, with several being approved for use in humans. Immunomodulatory drugs have shown success in dampening the deleterious inflammatory response seen in severe COVID-19 patients, but there remains an urgent need for development of additional therapeutic options for COVID-19 treatment. A potential drug target is the CCR5-CCL5 axis, and blocking this pathway may protect against severe disease. Here we evaluated whether OB-002, an analog of human CCL5 and a potent antagonist of CCR5, provides therapeutic benefit in SARS-CoV-2 infected Syrian hamsters. Daily treatment with OB-002 altered immune gene transcription in the lungs, and reduced pathology following infection, but did not prevent weight loss or viral replication in the lungs of infected animals, even in combination with the antiviral drug remdesivir. Our data suggest that targeting the CCR5-CCL5 pathway in SARS-CoV-2 infection in hamsters is insufficient to significantly impact disease development in this model.

Randomised, Placebo-Controlled, Double-Blind Trial to Assess Efficacy and Safety of ELOM-080 in Outpatients with COVID-19

INTRODUCTION

Incidences of infections with Severe Acute Respiratory Syndrome Coronavirus type 2 (SARS-CoV-2) are still high and treatment guidelines lack specific recommendations for outpatients with Coronavirus-induced disease 2019 (COVID-19). Phytomedicine ELOM-080, an enhancer of mucociliary clearance (MCC), showed benefits as add-on therapy in hospitalised COVID-19 patients.

METHODS

This randomised, double-blind, placebo-controlled proof-of-concept study investigated whether outpatients with mild to moderate acute symptomatic COVID-19 would benefit from a 14-day treatment with ELOM-080 with regard to potential early treatment effects on cough and further typical COVID-19 symptoms. Outpatients with mild to moderate acute symptomatic COVID-19 documented symptom severity and count of coughs on a daily basis. Investigators documented safety and symptom severity during the visits.

RESULTS

This study missed its primary objective, which was reduction in coughing fits in comparison to placebo treatment. In primary analysis, no relevant differences were observed between treatment arms. Data for all randomised patients showed broad heterogeneity in, e.g., time courses of coughing fits, which affected both magnitude and timing of the changes from baseline. However, post hoc analyses with a population with suspected dysfunctional MCC revealed that patients significantly benefitted from treatment with ELOM-080 in terms of reduction in coughing fits (p = 0.0070), difficulty breathing on exertion (p = 0.0252), and earlier remission of symptoms by 1-3 days.

CONCLUSION

We have shown that patients with dysfunctional MCC benefit from treatment with ELOM-080. These results might be of clinical importance, as up to now no therapy has obtained market approval for the treatment of outpatients with COVID-19.

TRIAL REGISTRATION

EudraCT number: 2022-003478-22.

Diketopiperazine/piperidine alkaloid as a potential broad-spectrum coronaviral entry inhibitor identified by supercomputer-based virtual screening from a large natural product-based library

The COVID-19 pandemic has underscored the urgent need for antiviral agents capable of targeting a broad range of coronaviruses, including emerging variants of SARS-CoV-2. While vaccines have been pivotal, the search for drugs that can prevent viral entry into host cells remains crucial, especially against evolving viral forms and other coronaviruses. In this study, we investigated natural products as a source of antiviral agents, focusing on their potential to block the spike protein's receptor-binding domain (RBD). Utilizing a library of over 210,000 natural product-based compounds from the ZINC database, we employed a Snakemake workflow to screen for inhibitors against RBDs of SARS-CoV-2, its variants, SARS-CoV, and MERS-CoV. Among top N-heterocyclic candidates from virtual screening we found that one compound, i.e., ((2 R,8S)-6-(1-benzylpiperidin-4-yl)-2-naphthalen-1-yl-3,6,17-triazatetracyclo[8.7.0.03,8.011,16]heptadeca-1(10),11,13,15 tetraene-4,7-dione), inhibited SARS-CoV-2 pseudovirus and live virus entry in HEK-ACE2 and Vero E6 host cells at low micromolar IC50 values. Cell viability assays showed that this compound exerted low cytotoxicity towards HEK-ACE2 while it was not toxic against Vero E6 and MRC5 cell lines. Microscale thermophoresis revealed that this compound strongly bound to the RBDs of SARS-CoV-2, SARS-CoV-2 XBB, SARS-CoV, MERS-CoV, and HCoV-HKU1, with their Kd values increasing as sequence similarity decreased. Molecular docking studies indicated this active compound binds to the SARS-CoV-2 spike protein RBD and interacts with hotspot amino acid residues required for the RBD-ACE2 interaction and cellular infection. These findings show that this diketopiperazine/piperidine-type alkaloid can be considered for further development as a potential pan-coronavirus entry inhibitor.

Macrophage‑driven pathogenesis in acute lung injury/acute respiratory disease syndrome: Harnessing natural products for therapeutic interventions (Review)

Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a common respiratory disease characterized by hypoxemia and respiratory distress. It is associated with high morbidity and mortality. Due to the complex pathogenesis of ALI, the clinical management of patients with ALI/ARDS is challenging, resulting in numerous post‑treatment sequelae and compromising the quality of life of patients. Macrophages, as a class of innate immune cells, play an important role in ALI/ARDS. In recent years, the functions and phenotypes of macrophages have been better understood due to the development of flow cytometry, immunofluorescence, single‑cell sequencing and spatial genomics. However, no macrophage‑targeted drugs for the treatment of ALI/ARDS currently exist in clinical practice. Natural products are important for drug development, and it has been shown that numerous natural compounds from herbal medicine can alleviate ALI/ARDS caused by various factors by modulating macrophage abnormalities. In the present review, the natural products from herbal medicine that can modulate macrophage abnormalities in ALI/ARDS to treat ALI/ARDS are introduced, and their mechanisms of action, discovered in the previous five years (2019‑2024), are presented. This will provide novel ideas and directions for further research, to develop new drugs for the treatment of ALI/ARDS.

The dual role of toll-like receptors in COVID-19: Balancing protective immunity and immunopathogenesis

Toll-like receptors (TLRs) of human are considered as the most critical immunological mediators of inflammatory pathogenesis of COVID-19. These immunoregulatory glycoproteins are located on the surface and/or intracellular compartment act as innate immune sensors. Upon binding with distinct SARS-CoV-2 ligand(s), TLRs signal activation of different transcription factors that induce expression of the proinflammatory mediators that collectively induce 'cytokine storm'. Similarly, TLR activation is also pivotal in conferring protection to infection and invasion as well as upregulating the tissue repair pathways. This dual role of the human TLRs in deciding the fate of SARS-CoV-2 has made these receptor proteins as the critical mediators of immunoprotective and immunopathogenic consequences associated with COVID-19. Herein, pathbreaking discoveries exploring the immunobiological importance of the TLRs in COVID-19 and developing TLR-directed therapeutic intervention have been reviewed by accessing the up-to-date literatures available in the public domain/databases. In accordance with our knowledge in association with the importance of TLRs' role against viruses and identification of viral particles, they have been recognized as suitable candidates with high potential as vaccine adjuvants. In this regard, the agonists of TLR4 and TLR9 have effective potential in vaccine technology while the others need further investigations. This comprehensive review suggests that basal level expression of TLRs can act as friends to keep our body safe from strangers but act as a foe via overexpression. Therefore, selective inhibition of the overexpressed TLRs appears to be a solution to counteract the cytokine storm while TLR-agonists as vaccine adjuvants could lessen the risk of infection in the naïve population.

Azelastine Nasal Spray in Non-Hospitalized Subjects with Mild COVID-19 Infection: A Randomized Placebo-Controlled, Parallel-Group, Multicentric, Phase II Clinical Trial

Nasal spray treatments that inhibit the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) entry into nose and nasopharynx at early stages can be an appropriate approach to stop or delay the progression of the disease. We performed a prospective, randomized, double-blind, placebo-controlled, parallel-group, multicentric, phase II clinical trial comparing the rate of hospitalization due to COVID-19 infection between azelastine 0.1% nasal spray and placebo nasal spray treatment groups. The study furthermore assessed the reduction in virus load in SARS-CoV-2-infected subjects estimated via quantitative reverse transcriptase polymerase chain reaction (RT-PCR) using nasopharyngeal swabs in both groups during the treatment period. A total of 294 subjects with mild COVID-19 infection were screened and randomized in a 1:1 ratio. There was no incidence of COVID-19-related hospitalization in either treatment group. Mean virus load was significantly reduced in both groups during the 11 treatment days as compared with baseline viral load values. The reduction in virus load in the azelastine 0.1% nasal spray group was significantly higher than the reduction in the placebo group at day 11 (log10 5.93 vs. log10 5.85 copies/mL, respectively, p = 0.0041). A total of 39 (32.0%) subjects in the azelastine 0.1% treatment group and 40 (31.0%) subjects in the placebo group reported 48 and 51 adverse events, respectively. It is therefore concluded that azelastine 0.1% nasal spray is an efficacious, safe, and well-tolerated treatment of mild COVID-19 infection.

Ideological Consistency and News Sharing as Predictors of Masking Among College Students

During the COVID-19 pandemic, the United States Centers for Disease Control and Prevention (CDC) recommended the use of well-fitting face masks or respirators as a strategy to reduce respiratory transmission; however, acceptance and utilization of face masks quickly became a contentious, politically charged matter. Given the effectiveness of masking against respiratory viruses, it is critical to understand the various normative factors and personal values associated with mask wearing. To this end, this study reports the findings of an online, cross-sectional survey (n = 1231) of college students during the COVID-19 pandemic. Findings show that ideological consistency, sharing news to create awareness, and sharing unverified news significantly predict masking behaviors, though ideological consistency most substantially explained variance in self-reported masking behaviors. Participants with more liberal political ideologies reported greater adherence to masking policies while those with more conservative ideologies reported less mask-wearing behavior. A better understanding of the predictors of masking behaviors, particularly how political ideologies continue to shape public health responses, is essential for designing more effective communication strategies to control disease spread and help inform strategies for future outbreaks. Study implications and limitations are discussed.

Viral Rebound After Antiviral Treatment: A Mathematical Modeling Study of the Role of Antiviral Mechanism of Action

The development of antiviral treatments for SARS-CoV-2 was an important turning point for the pandemic. Availability of safe and effective antivirals has allowed people to return back to normal life. While SARS-CoV-2 antivirals are highly effective at preventing severe disease, there have been concerning reports of viral rebound in some patients after cessation of antiviral treatment. In this study, we use a mathematical model of viral infection to study the potential of different antivirals to prevent viral rebound. We find that antivirals that block production are most likely to result in viral rebound if the treatment time course is not sufficiently long. Since these antivirals do not prevent infection of cells, cells continue to be infected during treatment. When treatment is stopped, the infected cells will begin producing virus at the usual rate. Antivirals that prevent infection of cells are less likely to result in viral rebound since cells are not being infected during treatment. This study highlights the role of antiviral mechanism of action in increasing or reducing the probability of viral rebound.

An in-depth analysis of COVID-19 treatment: Present situation and prospects

Coronavirus disease 2019 (COVID-19) the most contagious infection caused by the unique type of coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), produced a global pandemic that wreaked havoc on the health-care system, resulting in high morbidity and mortality. Several methods were implemented to tackle the virus, including the repurposing of existing medications and the development of vaccinations. The purpose of this article is to provide a complete summary of the current state and future possibilities for COVID-19 therapies. We describe the many treatment classes, such as antivirals, immunomodulators, and monoclonal antibodies, that have been repurposed or developed to treat COVID-19. We also looked at the clinical evidence for these treatments, including findings from observational studies and randomized-controlled clinical trials, and highlighted the problems and limitations of the available evidence. Furthermore, we reviewed existing clinical trials and prospective COVID-19 therapeutic options, such as novel medication candidates and combination therapies. Finally, we discussed the long-term consequences of COVID-19 and the importance of ongoing research into the development of viable treatments. This review will help physicians, researchers, and policymakers to understand the prevention and mitigation of COVID-19.

Oral complications during the two waves of COVID-19 pandemic in China: a prospective cross-section analysis of 510 cases using questionnaire

BACKGROUND

Oral complications such as parageusia, xerostomia, and oral ulcers are frequently observed in patients with COVID-19. The aim of this study was to understand the oral complications and their influencing factors during the two waves of the COVID-19 pandemic in China between December 2022 and May 2023.

METHODS

A total of 347 patients during the COVID-19 pandemic from December 2022 and January 2023 and 163 patients during the second COVID-19 pandemic were recruited through the Disease Prevention and Control Reporting System. Data on oral complications were collected via researcher-made questionnaires.

RESULTS

During both pandemic periods, more than 50% of the subjects developed oral complications. Specifically, the incidence of parageusia, pathological tongue coating, and xerostomia all exceeded 20%, while the incidence of oral ulcers surpassed 7%. Patients with allotriosmia and xerostomia had a significantly higher likelihood of developing other oral complications. Hospitalized patients requiring supplemental oxygen had a significantly higher incidence of oral complications.

CONCLUSIONS

The results of our study underline that oral complications during the COVID-19 pandemic are prevalent, and their incidence has not decreased during the subsequent pandemic. In the context of the ongoing global spread of COVID-19, this study lays the foundation for physicians in recognizing and managing oral complications, which will improve the oral health of communities globally.

Did the COVID-19 Pandemic Affect the Stress Levels among the Mothers of Premature Infants? A Narrative Review of the Present State of Knowledge, Prevention Strategies, and Future Directions

Understanding COVID-19's effects on susceptible populations remains essential for clinical implementations. Our review aimed to examine whether the pandemic significantly impacted the stress levels in the mothers of premature infants in NICUs. The review of the literature from Google Scholar and PubMed resulted in identifying specific stressors such as the disruption of healthcare systems, limited access to neonatal care, uncertainty due to frequent changes in restrictions, the risk of COVID-19 infection, social isolation, and financial stress. While some quantitative studies concerning this topic did not show a significant increase in the perception of stress in this population compared to the pre-pandemic group, various research has indicated that the COVID-19 pandemic may result in enduring impacts on the emotional and neurological development of children. This article demonstrates a correlation between the repercussions of the COVID-19 pandemic and an elevated incidence of depressive symptoms among the mothers of premature infants. Further studies are needed to assess the long-term impact of pandemic-induced stress.

A Natural Bioactive Peptide from Pinctada fucata Pearls Can Be Used as a Potential Inhibitor of the Interaction between SARS-CoV-2 and ACE2 against COVID-19

The frequent occurrence of viral infections poses a serious threat to human life. Identifying effective antiviral components is urgent. In China, pearls have been important traditional medicinal ingredients since ancient times, exhibiting various therapeutic properties, including detoxification properties. In this study, a peptide, KKCH, which acts against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was derived from Pinctada fucata pearls. Molecular docking showed that it bound to the same pocket of the SARS-CoV-2 S protein and cell surface target angiotensin-converting enzyme II (ACE2). The function of KKCH was analyzed through surface plasmon resonance (SPR), Enzyme-Linked Immunosorbent Assays, immunofluorescence, and simulation methods using the SARS-CoV-2 pseudovirus and live virus. The results showed that KKCH had a good affinity for ACE2 (KD = 6.24 × 10-7 M) and could inhibit the binding of the S1 protein to ACE2 via competitive binding. As a natural peptide, KKCH inhibited the binding of the SARS-CoV-2 S1 protein to the surface of human BEAS-2B and HEK293T cells. Moreover, viral experiments confirmed the antiviral activity of KKCH against both the SARS-CoV-2 spike pseudovirus and SARS-CoV-2 live virus, with half-maximal inhibitory concentration (IC50) values of 398.1 μM and 462.4 μM, respectively. This study provides new insights and potential avenues for the prevention and treatment of SARS-CoV-2 infections.

Medicinal plants used in Gabon for prophylaxis and treatment against COVID-19-related symptoms: an ethnobotanical survey

Background: Gabon faced COVID-19 with more than 49,000 individuals tested positive and 307 recorded fatalities since the first reported case in 2020. A popular hypothesis is that the low rate of cases and deaths in the country was attributed to the use of medicinal plants in prevention and treatment. This study aimed to document the plants used for remedial and preventive therapies by the Gabonese population during the COVID-19 pandemic and to pinpoint specific potential plant species that merit further investigation. Methods: An ethnobotanical survey involving 97 participants was conducted in Libreville. Traditional healers and medicinal plant vendors were interviewed orally using a semi-structured questionnaire sheet, while the general population responded to an online questionnaire format. Various quantitative indexes were calculated from the collected data and included the relative frequency of citation (RFC), use value (UV), informant consensus factor (ICF), relative importance (RI), and popular therapeutic use value (POPUT). One-way ANOVA and independent samples t-test were used for statistical analyses. p-values ≤0.05 were considered significant. Results: The survey identified 63 plant species belonging to 35 families. Prevalent symptoms treated included fever (18%), cough (16%), fatigue (13%), and cold (12%). The demographic data highlighted that 52.58% of male subjects (p > 0.94) aged 31-44 years were enrolled in the survey, of which 48.45% (p < 0.0001) and 74.73% (p < 0.99) of informants had university-level education. In addition, the results indicated that a total of 66% of the informants used medicinal plants for prophylaxis (34%), for both prevention and treatment (26%), exclusively for treatment (3%), and only for prevention (3%) while suffering from COVID-19, against 34% of the participants who did not use plants for prevention or treatment. Annickia chlorantha, Citrus sp., Alstonia congensis, Zingiber officinale, and Carica papaya emerged as the most commonly cited plants with the highest RFC (0.15-0.26), UV (0.47-0.75), and RI (35.72-45.46) values. Most of these plants were used either individually or in combination with others. Conclusion: The survey reinforces the use of traditional medicine as a method to alleviate COVID-19 symptoms, thereby advocating for the utilization of medicinal plants in managing coronavirus infections.

Comparison of effectiveness and safety of nirmatrelvir/ritonavir versus sotrovimab for COVID-19: a systematic review and meta-analysis

BACKGROUND

This study aims to compare the effectiveness and safety of nirmatrelvir/ritonavir (Paxlovid) and sotrovimab for coronavirus disease 2019 (COVID-19).

METHODS

A search was conducted on PubMed, Cochrane Library, and Web of Science to explore relevant studies from January 2021 to November 2023. The risk of bias in the included studies was assessed using the Cochrane Collaboration's tool. Data analysis was conducted using the Comprehensive Meta-Analysis software (version 3.0).

RESULTS

Fifteen retrospective studies involving 13, 306 patients were included. The meta-analysis revealed no significant difference between the nirmatrelvir/ritonavir and sotrovimab groups in terms of mortality rate (odds ratio [OR] = 0.62, 95% confidence interval [CI]: 0.28 to 1.38), hospitalization rate (OR = 0.76, 95% CI: 0.48 to 1.22), death or hospitalization rate (OR = 0.75, 95% CI: 0.51 to 1.10), and intensive unit care admission (OR = 1.97, 95% CI: 0.38 to 10.07). In terms of safety, nirmatrelvir/ritonavir was associated with a higher incidence of adverse events (OR = 3.44, 95% CI: 1.29 to 9.17).

CONCLUSIONS

The meta-analysis showed that nirmatrelvir/ritonavir and sotrovimab have similar effectiveness in treating COVID-19 patients. However, the certainty of evidence supporting these findings is low. High-quality research is needed to better compare these interventions in COVID-19.

Effect of methotrexate hold on COVID-19 vaccine response in the patients with autoimmune inflammatory disorders: a systematic review and meta-analysis

Immunosuppressants, such as methotrexate (MTX), can suppress the COVID-19 vaccine response in patients with autoimmune diseases. Thus, this study aims to evaluate the effects of MTX hold following COVID-19 vaccination on vaccine efficacy response. A systematic review and meta-analysis of relevant studies retrieved from Web of Science, SCOPUS, PubMed, and CENTRAL from inception until Oct 1, 2023, was conducted. Covidence was used to screen the eligible articles, and all relevant outcomes data were synthesized using risk ratios (RRs) or standardized mean differences (SMDs) with 95% confidence intervals (CIs) in meta-analysis models within RevMan 5.4. PROSPERO ID: CRD42024511628. Four studies with a total of 762 patients with autoimmune inflammatory disorders were included. Holding MTX following the COVID-19 vaccination for approximately 2 weeks was associated with significantly higher antibody titer (SMD: 0.70, 95% CI [0.54, 0.87], P < 0.00001). However, the flare rate was significantly higher in the MTX hold group based on CDAI > 10 or DAS28-CRP > 1.2 either after 1st dose (RR: 2.49 with 95% CI [1.39, 4.47], P = 0.002) or 2nd dose (RR: 2.16 with 95% CI [1.37, 3.41], P = 0.0009) and self-reported disease flare (RR: 1.71 with 95% CI [1.35, 2.17], P < 0.00001). Holding MTX for 2 weeks after the COVID-19 vaccination resulted in significantly higher antibody titer but also had a higher disease flare rate, necessitating cautious clinical monitoring during this period. There is still a need to investigate safer MTX hold duration, considering patients' vulnerability to COVID-19, disease status, and demographics while adopting this strategy.

The role of hematological parameters in asymptomatic and non-severe cases of Omicron variant infection

BACKGROUND

Omicron variants are currently the predominant circulating lineage worldwide and most cases are mild or asymptomatic. The Omicron variant is characterized by high transmissibility and immune evasion. Early identification of Omicron cases in clinical settings is crucial for controlling its spread. Previous studies have indicated that changes in hematological parameters can be used to predict the severity of coronavirus disease 2019 (COVID-19). However, the role of hematological parameters in non-severe and asymptomatic cases remains unknown. This study aimed to investigate the role of hematological parameters in non-severe and asymptomatic Omicron variant infections.

METHODS

Hematological parameters and results were analyzed and compared in symptomatic (n = 356) and asymptomatic (n = 171) groups respectively, and between these two groups with positive COVID-19 tests. The utility of hematological parameters for predicting positive COVID-19 tests was analyzed using receiver operating characteristic curves.

RESULTS

Individuals with non-severe cases exhibited decreased levels of platelets, lymphocytes, eosinophils, basophils, lymphocytes (%), eosinophils (%), and basophils (%), while exhibiting elevated counts of monocytes, neutrophils (%), monocytes (%), neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), and C-reactive protein (CRP) when compared to suspected cases or asymptomatic carriers. In asymptomatic patients, positive carriers had lower leukocyte, neutrophil, and lymphocyte counts but higher monocyte, monocyte (%), PLR, and CRP levels than negative carriers. Basophil counts combined with lymphocytes or the PLR demonstrated a more significant predictive value in screening non-severe cases earlier compared to other parameters. The combined assessment of the monocyte (%) and the PLR had the highest area under the curve for diagnosing asymptomatic carriers.

CONCLUSIONS

Circulating basophils, alone or in combination with other hematological parameters, may be used as efficient biomarkers for early screening of non-severe Omicron cases.

The Review of Ophthalmic Symptoms in COVID-19

The COVID-19 pandemic caused by SARS-CoV-2 had a significant impact on the health of the global human population, affecting almost every human organ, including the organ of vision. Research focus on understanding the pathophysiology, identifying symptoms and complications of the disease. Eye-related pathologies are important foci of research due to the potential for direct impact of the virus. Ophthalmologists around the world are reporting various symptoms of eye infections and ocular pathologies associated with SARS-CoV-2. The review of ophthalmic symptoms was conducted to help physicians of various specialties recognize possible ophthalmic manifestations of this viral disease. A literature review was conducted from January 2020 to July 2023 in the PubMed, MEDLINE, Science Direct, Scopus, Scielo and Google Scholar databases. The review of the literature showed that conjunctivitis is the most common ophthalmic symptom observed during the course of COVID-19 and can occur at any stage of the disease. Changes in the eye may result from the direct effect of the virus, immune response, prothrombotic states, comorbidities, and medications used. Symptoms related to the organ of vision can be divided into: changes affecting the protective apparatus of the eye, the anterior eye segment, the posterior eye segment, neuro-ophthalmic, and orbital changes. Ocular symptoms may suggest COVID-19 infection or appear several weeks after recovery. Following COVID-19 vaccinations, a diverse range of ophthalmic symptoms was observed in various locations and at different times, mirroring the ocular symptoms experienced throughout the course of the COVID-19 illness. It is important for physicians of all specialties to be aware of possible potential connections between eye diseases and SARS-CoV-2, in order to effectively diagnose and treat patients.

The metabolic footprint of Vero E6 cells highlights the key metabolic routes associated with SARS-CoV-2 infection and response to drug combinations

SARS-CoV-2 burdens healthcare systems worldwide, yet specific drug-based treatments are still unavailable. Understanding the effects of SARS-CoV-2 on host molecular pathways is critical for providing full descriptions and optimizing therapeutic targets. The present study used Nuclear Magnetic Resonance-based metabolic footprinting to characterize the secreted cellular metabolite levels (exometabolomes) of Vero E6 cells in response to SARS-CoV-2 infection and to two candidate drugs (Remdesivir, RDV, and Azithromycin, AZI), either alone or in combination. SARS-CoV-2 infection appears to force VE6 cells to have increased glucose concentrations from extra-cellular medium and altered energetic metabolism. RDV and AZI, either alone or in combination, can modify the glycolic-gluconeogenesis pathway in the host cell, thus impairing the mitochondrial oxidative damage caused by the SARS-CoV-2 in the primary phase. RDV treatment appears to be associated with a metabolic shift toward the TCA cycle. Our findings reveal a metabolic reprogramming produced by studied pharmacological treatments that protects host cells against virus-induced metabolic damage, with an emphasis on the glycolytic-gluconeogenetic pathway. These findings may help researchers better understand the relevant biological mechanisms involved in viral infection, as well as the creation of mechanistic hypotheses for such candidate drugs, thereby opening up new possibilities for SARS-CoV-2 pharmacological therapy.

Lipid Nanoparticle-Based Inhibitors for SARS-CoV-2 Host Cell Infection

Purpose

The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the lingering threat to public health has fueled the search for effective therapeutics to treat SARS-CoV-2. This study aimed to develop lipid nanoparticle (LNP) inhibitors of SARS-CoV-2 entry to reduce viral infection in the nose and upper airway.

Methods

Two types of LNP formulations were prepared following a microfluidic mixing method. The LNP-Trap consisted of DOPC, DSPC, cholesterol, and DSPE-PEG-COOH modified with various spike protein binding ligands, including ACE2 peptide, recombinant human ACE2 (rhACE2) or monoclonal antibody to spike protein (mAb). The LNP-Trim consisted of ionizing cationic DLin-MC3-DMA, DSPC, cholesterol, and DMG-PEG lipids encapsulating siACE2 or siTMPRSS2. Both formulations were assayed for biocompatibility and cell uptake in airway epithelial cells (Calu-3). Functional assessment of activity was performed using SARS-CoV-2 spike protein binding assays (LNP-Trap), host receptor knockdown (LNP-Trim), and SARS-CoV-2 pseudovirus neutralization assay (LNP-Trap and LNP-Trim). Localization and tissue distribution of fluorescently labeled LNP formulations were assessed in mice following intranasal administration.

Results

Both LNP formulations were biocompatible based on cell impedance and MTT cytotoxicity studies in Calu-3 cells at concentrations as high as 1 mg/mL. LNP-Trap formulations were able to bind spike protein and inhibit pseudovirus infection by 90% in Calu-3 cells. LNP-Trim formulations reduced ACE2 and TMPRSS2 at the mRNA (70% reduction) and protein level (50% reduction). The suppression of host targets in Calu-3 cells treated with LNP-Trim resulted in over 90% inhibition of pseudovirus infection. In vivo studies demonstrated substantial retention of LNP-Trap and LNP-Trim in the nasal cavity following nasal administration with minimal systemic exposure.

Conclusion

Both LNP-Trap and LNP-Trim formulations were able to safely and effectively inhibit SARS-CoV-2 pseudoviral infection in airway epithelial cells. These studies provide proof-of-principle for a localized treatment approach for SARS-CoV-2 in the upper airway.

Characterization of Omicron BA.4.6, XBB, and BQ.1.1 subvariants in hamsters

During the Omicron wave, previous variants such as BA.2, BA.4, and BA.5 were replaced by newer variants with additional mutations in the spike protein. These variants, BA.4.6, BQ.1.1, and XBB, have spread in different countries with different degrees of success. Here, we evaluated the replicative ability and pathogenicity of BA.4.6, BQ1.1, and XBB clinical isolates in male Syrian hamsters. Although we found no substantial differences in weight change among hamsters infected with these Omicron subvariants, the replicative ability of BQ.1.1 and XBB in lung tissue was higher than that of BA.4.6 and BA.5. Of note, BQ.1.1 was lethal in both male and female transgenic human ACE2 hamsters. In competition assays, XBB replicated better than BQ.1.1 in the nasal turbinate tissues of female hamsters previously infected with Omicron BA.2. These results suggest that newer Omicron subvariants in the XBB family are still evolving and should be closely monitored.

Therapeutic utility of human umbilical cord-derived mesenchymal stem cells-based approaches in pulmonary diseases: Recent advancements and prospects

Pulmonary diseases across all ages threaten millions of people and have emerged as one of the major public health issues worldwide. For diverse disease conditions, the currently available approaches are focused on alleviating clinical symptoms and delaying disease progression but have not shown significant therapeutic effects in patients with lung diseases. Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) isolated from the human UC have the capacity for self-renewal and multilineage differentiation. Moreover, in recent years, these cells have been demonstrated to have unique advantages in the treatment of lung diseases. We searched the Public Clinical Trial Database and found 55 clinical trials involving UC-MSC therapy for pulmonary diseases, including coronavirus disease 2019, acute respiratory distress syndrome, bronchopulmonary dysplasia, chronic obstructive pulmonary disease, and pulmonary fibrosis. In this review, we summarize the characteristics of these registered clinical trials and relevant published results and explore in depth the challenges and opportunitiesfaced in clinical application. Moreover, the underlying molecular mechanisms involved in UC-MSC-based therapy for pulmonary diseases are also analyzed in depth. In brief, this comprehensive review and detailed analysis of these clinical trials can be expected to provide a scientific reference for future large-scale clinical application.

Comparing plasma and skin imprint metabolic profiles in COVID-19 diagnosis and severity assessment

As SARS-CoV-2 continues to produce new variants, the demand for diagnostics and a better understanding of COVID-19 remain key topics in healthcare. Skin manifestations have been widely reported in cases of COVID-19, but the mechanisms and markers of these symptoms are poorly described. In this cross-sectional study, 101 patients (64 COVID-19 positive patients and 37 controls) were enrolled between April and June 2020, during the first wave of COVID-19, in São Paulo, Brazil. Enrolled patients had skin imprints sampled non-invasively using silica plates; plasma samples were also collected. Samples were used for untargeted lipidomics/metabolomics through high-resolution mass spectrometry. We identified 558 molecular ions, with lipids comprising most of them. We found 245 plasma ions that were significant for COVID-19 diagnosis, compared to 61 from the skin imprints. Plasma samples outperformed skin imprints in distinguishing patients with COVID-19 from controls, with F1-scores of 91.9% and 84.3%, respectively. Skin imprints were excellent for assessing disease severity, exhibiting an F1-score of 93.5% when discriminating between patient hospitalization and home care statuses. Specifically, oleamide and linoleamide were the most discriminative biomarkers for identifying hospitalized patients through skin imprinting, and palmitic amides and N-acylethanolamine 18:0 were also identified as significant biomarkers. These observations underscore the importance of primary fatty acid amides and N-acylethanolamines in immunomodulatory processes and metabolic disorders. These findings confirm the potential utility of skin imprinting as a valuable non-invasive sampling method for COVID-19 screening; a method that may also be applied in the evaluation of other medical conditions. KEY MESSAGES: Skin imprints complement plasma in disease metabolomics. The annotated markers have a role in immunomodulation and metabolic diseases. Skin imprints outperformed plasma samples at assessing disease severity. Skin imprints have potential as non-invasive sampling strategy for COVID-19.

The Microbiota in Long COVID

Interest in the coronavirus disease 2019 (COVID-19) has progressively decreased lately, mainly due to the great effectivity of vaccines. Furthermore, no new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants able to circumvent the protection of these vaccines, while presenting high transmissibility and/or lethality, have appeared. However, long COVID has emerged as a huge threat to human health and economy globally. The human microbiota plays an important role in health and disease, participating in the modulation of innate and adaptive immune responses. Thus, multiple studies have found that the nasopharyngeal microbiota is altered in COVID-19 patients, with these changes associated with the onset and/or severity of the disease. Nevertheless, although dysbiosis has also been reported in long COVID patients, mainly in the gut, little is known about the possible involvement of the microbiota in the development of this disease. Therefore, in this work, we aim to fill this gap in the knowledge by discussing and comparing the most relevant studies that have been published in this field up to this point. Hence, we discuss that the relevance of long COVID has probably been underestimated, and that the available data suggest that the microbiota could be playing a pivotal role on the pathogenesis of the disease. Further research to elucidate the involvement of the microbiota in long COVID will be essential to explore new therapeutic strategies based on manipulation of the microbiota.

Immune characteristics of kidney transplant recipients with acute respiratory distress syndrome induced by COVID-19 at single-cell resolution

BACKGROUND

COVID-19-induced acute respiratory distress syndrome (ARDS) can result in tissue damage and multiple organ dysfunction, especially in kidney transplant recipients (KTRs) receiving immunosuppressive drugs. Presently, single-cell research on COVID-19-induced ARDS is considerably advanced, yet knowledge about ARDS in KTRs is still constrained.

METHODS

Single-cell RNA sequencing (scRNA-seq) analysis was performed to construct a comprehensive single-cell immune landscape of the peripheral blood mononuclear cells (PBMCs) of eight patients with COVID-19-induced ARDS, five KTRs with COVID-19-induced ARDS, and five healthy individuals. Subsequently, we conducted a comprehensive bioinformatics analysis, including cell clustering, enrichment analysis, trajectory analysis, gene regulatory network analysis, and cell-cell interaction analysis, to investigate the heterogeneity of the immune microenvironment in KTRs with ARDS.

RESULT

Our study revealed that KTRs exhibit significant heterogeneity with COVID-19-induced ARDS compared with those of other individuals, with significant reductions in T cells, as well as an abnormal proliferation of B cells and monocytes. In the context of dual influences from immunosuppression and viral infection, KTRs exhibited more specific plasma cells, along with significant enrichment of dysfunctional GZMB and XAF1 double-positive effector T cells and IFI27-positive monocytes. Additionally, robust communication existed among T cells and monocytes in cytokine signaling. These effects impede the process of immune reconstitution in KTR patients.

CONCLUSION

Our findings suggest that KTRs with COVID-19-induced ARDS show elevated antibody levels, impaired T cell differentiation, and dysregulation of innate immunity. In summary, this study provides a theoretical foundation for a comprehensive understanding of COVID-19-induced ARDS in KTRs.

Elucidating the binding mechanism of SARS-CoV-2 NSP6-TBK1 and structure-based designing of phytocompounds inhibitors for instigating the host immune response

SARS-CoV-2, also referred to as severe acute respiratory syndrome coronavirus 2, is the virus responsible for causing COVID-19, an infectious disease that emerged in Wuhan, China, in December 2019. Among its crucial functions, NSP6 plays a vital role in evading the human immune system by directly interacting with a receptor called TANK-binding kinase (TBK1), leading to the suppression of IFNβ production. Consequently, in the present study we used the structural and biophysical approaches to analyze the effect of newly emerged mutations on the binding of NSP6 and TBK1. Among the identified mutations, four (F35G, L37F, L125F, and I162T) were found to significantly destabilize the structure of NSP6. Furthermore, the molecular docking analysis highlighted that the mutant NSP6 displayed its highest binding affinity with TBK1, exhibiting docking scores of -1436.2 for the wildtype and -1723.2, -1788.6, -1510.2, and -1551.7 for the F35G, L37F, L125F, and I162T mutants, respectively. This suggests the potential for an enhanced immune system evasion capability of NSP6. Particularly, the F35G mutation exhibited the strongest binding affinity, supported by a calculated binding free energy of -172.19 kcal/mol. To disrupt the binding between NSP6 and TBK1, we conducted virtual drug screening to develop a novel inhibitor derived from natural products. From this screening, we identified the top 5 hit compounds as the most promising candidates with a docking score of -6.59 kcal/mol, -6.52 kcal/mol, -6.32 kcal/mol, -6.22 kcal/mol, and -6.21 kcal/mol. The molecular dynamic simulation of top 3 hits further verified the dynamic stability of drugs-NSP6 complexes. In conclusion, this study provides valuable insight into the higher infectivity of the SARS-CoV-2 new variants and a strong rationale for the development of novel drugs against NSP6.

Budget impact of oral nirmatrelvir/ritonavir in adults at high risk for progression to severe COVID-19 in the United States

BACKGROUND

Nirmatrelvir/ritonavir (NMV/r) is indicated for the treatment of mild-to-moderate COVID-19 in adults who are at high risk for progression to severe COVID-19. NMV/r has also been authorized for emergency use by the US Food and Drug Administration for the treatment of mild-to-moderate COVID-19 in pediatric patients (aged 226512 years and weighing at least 40 kg) who are at high risk for progression to severe COVID-19. Understanding the budget impact of introducing NMV/r for the treatment of adults with COVID-19 is of key interest to US payers.

OBJECTIVE

To estimate the annual budget impact of introducing NMV/r in a US commercial health plan setting in the current Omicron COVID-19 era.

METHODS

A budget impact model was developed to assess the impact of NMV/r on health care costs in a hypothetical 1-million-member commercial health insurance plan over a 1-year period in the US population; clinical and cost inputs were derived from published literature with a focus on studies in the recent COVID-19 era that included vaccinated population and predominance of the Omicron variant. In the base-case analysis, it was assumed the only effect of NMV/r was a reduction in incidence (not severity) of hospitalization or death; its potential effect on post-COVID conditions was assessed in a scenario analysis. Outcomes included the number of hospitalizations, total cost, per patient per year (PPPY) costs, and per member per month (PMPM) costs. Sensitivity and scenario analyses were conducted to assess uncertainty around key model inputs.

RESULTS

An estimated 29,999 adults were eligible and sought treatment with oral antiviral for COVID-19 over 1 year. The availability of NMV/r was estimated to reduce the number of hospitalizations by 647 with a total budget impact of $2,733,745, $91 PPPY, and $0.23 PMPM. NMV/r was cost saving when including post-COVID conditions with a -$1,510,780 total budget impact, a PPPY cost of -$50, and a PMPM cost of -$0.13. Sensitivity analyses indicated results were most sensitive to the risk of hospitalization under supportive care, risk of hospitalization with NMV/r treatment and cost of NMV/r.

CONCLUSIONS

Treatment with NMV/r in the current COVID-19 era is estimated to result in substantial cost offsets because of reductions in hospitalization and modest budget impact to potential overall cost savings.

Amplification of poly(I:C)-induced interleukin-6 production in human bronchial epithelial cells by priming with interferon-γ

Proinflammatory cytokine interleukin (IL)-6 was associated with disease severity in patients with COVID-19. The mechanism underlying the excessive IL-6 production by SARS-Cov-2 infection remains unclear. Respiratory viruses initially infect nasal or bronchial epithelial cells that produce various inflammatory mediators. Here, we show that pretreatment of human bronchial epithelial cells (NCl-H292) with interferon (IFN)-γ (10 ng/mL) markedly increased IL-6 production induced by the toll-like receptor (TLR) 3 agonist poly(I:C) (1 µg/mL) from 0.4 ± 0.1 to 4.1 ± 0.4 ng/mL (n = 3, P < 0.01). A similar effect was observed in human alveolar A549 and primary bronchial epithelial cells. TLR3 knockdown using siRNA in NCl-H292 cells diminished the priming effects of IFN-γ on poly(I:C)-induced IL-6 production. Furthermore, the Janus kinase (JAK) inhibitor tofacitinib (1 µM) inhibited IFN-γ-induced upregulation of TLR3, and suppressed poly(I:C)-induced IL-6 production. Quantitative chromatin immunoprecipitation revealed that IFN-γ stimulated histone modifications at the IL-6 gene locus. Finally, IFN-γ priming significantly increased lung IL-6 mRNA and protein levels in poly(I:C)-administrated mice. Thus, priming bronchial epithelial cells with IFN-γ increases poly(I:C)-induced IL-6 production via JAK-dependent TLR3 upregulation and chromatin remodeling at the IL-6 gene locus. These mechanisms may be involved in severe respiratory inflammation following infection with RNA viruses.

Polypharmacy and the In Silico Prediction of Potential Body Proteins Targeted by These Drugs Among Hospitalized COVID-19 Patients With Cytokine Storm

Background and objective Polypharmacy is prevalent in coronavirus disease 2019 (COVID-19) patients with severe disease. However, information on polypharmacy among COVID-19 patients who also suffer from cytokine storm is scarce. In light of this, the purpose of the present study was to assess the incidence of polypharmacy and in silico prediction of potential body proteins targeted by these drugs among hospitalized COVID-19 patients who were identified to have the additional burden of cytokine storm in the city of Duhok, Kurdistan Region, Iraq. Methods This was a cross-sectional observational study conducted from June 2021 to April 2022; the phenomena of major polypharmacy (six to nine medications) and excessive polypharmacy (≥10 medications) were documented among 33 (15 males and 18 females) COVID-19 patients with cytokine storm during their hospital stay (8-45 days) in Duhok, Kurdistan Region, Iraq. The SwissTargetPrediction program was utilized in silico to predict and identify human body proteins that could be potentially targeted by selected medications involved in polypharmacy. Results All patients had tested positive for COVID-19 via PCR testing, and they showed different signs and symptoms of the disease. None of the patients recovered and all of them deceased. All 33 patients received many therapeutic agents that ranged in number from eight to 20/patient during their hospital stay. The mean number of medications was 15 ± 3. We identified 2/33 (6%) patients with major polypharmacy (eight and nine) and 31/33 (94%) with excessive polypharmacy (15.5 ± 2.7). The total number of medications identified in polypharmacy was 37, excluding vitamins, minerals, and intravenous solutions. The frequency of medications administered was as follows: antibiotics (67, 13.7%), mucolytic agents (56, 11.5%), corticosteroids (54, 11%), anticoagulants (48, 9.8%), antiviral agents (41, 8.4%), antihypertensive agents (32, 6.5%), analgesics (28, 5.7%), antifungal drugs (27, 5.5%), antidiabetics (26, 5.3%), and other medications (2-19, 0.41-3.9%). Using the SwissTargetPrediction program, various drugs including antiviral agents involved in polypharmacy were found to target, in silico, body proteins at a prediction percentage that ranged from 6.7% to 40%. Conclusions Major and extensive polypharmacy conditions were identified in hospitalized COVID-19 patients suffering from cytokine storm. The severity of COVID-19 with cytokine storm, comorbidities, and hospitalization were key factors associated with polypharmacy in the patients. The SwissTargetPrediction web server is useful for predicting in silico potential human body protein targets that could possibly be sources of additional information on the adverse/toxic effects of polypharmacy medications administered concurrently. Further research in current medication protocols prescribed for advanced COVID-19 illness with cytokine storm is warranted to gain deeper insights into the topic.

Benzimidazole-Triazole Hybrids as Antimicrobial and Antiviral Agents: A Systematic Review

Bacterial infections have attracted the attention of researchers in recent decades, especially due to the special problems they have faced, such as their increasing diversity and resistance to antibiotic treatment. The emergence and development of the SARS-CoV-2 infection stimulated even more research to find new structures with antimicrobial and antiviral properties. Among the heterocyclic compounds with remarkable therapeutic properties, benzimidazoles, and triazoles stand out, possessing antimicrobial, antiviral, antitumor, anti-Alzheimer, anti-inflammatory, analgesic, antidiabetic, or anti-ulcer activities. In addition, the literature of the last decade reports benzimidazole-triazole hybrids with improved biological properties compared to the properties of simple mono-heterocyclic compounds. This review aims to provide an update on the synthesis methods of these hybrids, along with their antimicrobial and antiviral activities, as well as the structure-activity relationship reported in the literature. It was found that the presence of certain groups grafted onto the benzimidazole and/or triazole nuclei (-F, -Cl, -Br, -CF₃, -NO₂, -CN, -CHO, -OH, OCH₃, COOCH₃), as well as the presence of some heterocycles (pyridine, pyrimidine, thiazole, indole, isoxazole, thiadiazole, coumarin) increases the antimicrobial activity of benzimidazole-triazole hybrids. Also, the presence of the oxygen or sulfur atom in the bridge connecting the benzimidazole and triazole rings generally increases the antimicrobial activity of the hybrids. The literature mentions only benzimidazole-1,2,3-triazole hybrids with antiviral properties. Both for antimicrobial and antiviral hybrids, the presence of an additional triazole ring increases their biological activity, which is in agreement with the three-dimensional binding mode of compounds. This review summarizes the advances of benzimidazole triazole derivatives as potential antimicrobial and antiviral agents covering articles published from 2000 to 2023.

Unpacking the Complexity of COVID-19 Fatalities: Adverse Events as Contributing Factors-A Single-Center, Retrospective Analysis of the First Two Years of the Pandemic

In a retrospective analysis of 477 fatal COVID-19 cases hospitalised at a single medical centre during the period from 6 March 2020 to 30 June 2022, several factors defining those patients at admission were assessed, as well as the course of the hospitalisation and factors contributing to death. There was a predominance of men (59.3% (283)) burdened by comorbidities, with increased inflammation at admission. Patients aged ≥ 81 years were significantly more likely to be admitted to and die in infectious diseases units (IDU) due to respiratory failure, their hospital stays were shorter, and they were most likely not to receive specialist treatment. The most common COVID-19 complications included acute kidney injury in 31.2% (149) patients and thromboembolic complications in 23.5% (112). The course of hospitalisation was complicated by healthcare-associated infections (HAI) in 33.3% (159) of cases, more often in those treated with baricitinib (p < 0.001). The initial use of an antibiotic, although common (94.8% (452)), was unwarranted in almost half of the cases (47.6% (215)). Complications of hospitalisation (46.1% (220)) and adverse events involving staff (49.7% (237)) were found in almost half of the patients. In 88.7% (423) of the cases, death was due to respiratory failure in the course of SARS-CoV-2 infection. Adverse events during hospitalisation should be considered as an additional factor that, in addition to the infection itself, may have influenced the death of patients.

Pharmacological approaches to pulmonary fibrosis following COVID-19

Background: In the past few years, COVID-19 became the leading cause of morbidity and mortality worldwide. Although the World Health Organization has declared an end to COVID-19 as a public health emergency, it can be expected, that the emerging new cases at the top of previous ones will result in an increasing number of patients with post-COVID-19 sequelae. Despite the fact that the majority of patients recover, severe acute lung tissue injury can in susceptible individuals progress to interstitial pulmonary involvement. Our goal is to provide an overview of various aspects associated with the Post-COVID-19 pulmonary fibrosis with a focus on its potential pharmacological treatment options. Areas covered: We discuss epidemiology, underlying pathobiological mechanisms, and possible risk and predictive factors that were found to be associated with the development of fibrotic lung tissue remodelling. Several pharmacotherapeutic approaches are currently being applied and include anti-fibrotic drugs, prolonged use or pulses of systemic corticosteroids and non-steroidal anti-inflammatory and immunosuppressive drugs. In addition, several repurposed or novel compounds are being investigated. Fortunately, clinical trials focused on pharmacological treatment regimens for post-COVID-19 pulmonary fibrosis have been either designed, completed or are already in progress. However, the results are contrasting so far. High quality randomised clinical trials are urgently needed with respect to the heterogeneity of disease behaviour, patient characteristics and treatable traits. Conclusion: The Post-COVID-19 pulmonary fibrosis contributes to the burden of chronic respiratory consequences among survivors. Currently available pharmacotherapeutic approaches mostly comprise repurposed drugs with a proven efficacy and safety profile, namely, corticosteroids, immunosuppressants and antifibrotics. The role of nintedanib and pirfenidone is promising in this area. However, we still need to verify conditions under which the potential to prevent, slow or stop progression of lung damage will be fulfilled.

Identification of Potential TMPRSS2 Inhibitors for COVID-19 Treatment in Chinese Medicine by Computational Approaches and Surface Plasmon Resonance Technology

BACKGROUND

Coronavirus disease-19 (COVID-19) pneumonia continues to spread in the entire globe with limited medication available. In this study, the active compounds in Chinese medicine (CM) recipes targeting the transmembrane serine protease 2 (TMPRSS2) protein for the treatment of COVID-19 were explored.

METHODS

The conformational structure of TMPRSS2 protein (TMPS2) was built through homology modeling. A training set covering TMPS2 inhibitors and decoy molecules was docked to TMPS2, and their docking poses were re-scored with scoring schemes. A receiver operating characteristic (ROC) curve was applied to select the best scoring function. Virtual screening of the candidate compounds (CCDs) in the six highly effective CM recipes against TMPS2 was conducted based on the validated docking protocol. The potential CCDs after docking were subject to molecular dynamics (MD) simulations and surface plasmon resonance (SPR) experiment.

RESULTS

A training set of 65 molecules were docked with modeled TMPS2 and LigScore2 with the highest area under the curve, AUC, value (0.886) after ROC analysis selected to best differentiate inhibitors from decoys. A total of 421 CCDs in the six recipes were successfully docked into TMPS2, and the top 16 CCDs with LigScore2 higher than the cutoff (4.995) were screened out. MD simulations revealed a stable binding between these CCDs and TMPS2 due to the negative binding free energy. Lastly, SPR experiments validated the direct combination of narirutin, saikosaponin B1, and rutin with TMPS2.

CONCLUSIONS

Specific active compounds including narirutin, saikosaponin B1, and rutin in CM recipes potentially target and inhibit TMPS2, probably exerting a therapeutic effect on COVID-19.

Determining half-life of SARS-CoV-2 antigen in respiratory secretion

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is primarily transmitted from person to person through respiratory droplets and aerosols. It is also possible for the virus to be transmitted indirectly through environmental contamination. The likelihood of environmental transmission depends on several factors, including the survival time of the virus in respiratory secretions. However, the stability of SARS-CoV-2 in respiratory secretions has not been investigated. In this study, we compared the half-life of the SARS-CoV-2 antigen in respiratory secretion under different conditions. We applied respiratory secretion (5 µL) to glass slides, air-dried the slides for 1 h, and kept them at 24 °C or 4 °C for 10 days. Respiratory secretions were also placed in test tubes (sealed to preserve moisture) and in normal saline for 10 days. The concentration of SARS-CoV-2 antigen in all samples was simultaneously measured using colloidal gold immunochromatography, and the half-life of the antigen was calculated. The half-life of the antigen in the wet (sealed tube) and saline samples at room temperature was 5.0 and 2.92 days, respectively. The half-life of the antigen in the air-dried sample at room temperature and at 4 °C was 2.93 and 11.4 days, respectively. The half-life was longer in respiratory secretions than that in normal saline. The half-life was also longer in respiratory secretions, at a lower temperature, and under wet conditions. Therefore, environmental transmission can also play a significant role in the spread of the virus. Robust prevention and control strategies could be developed based on the half-life of the antigen in respiratory secretions.