Age-Related Differences in Immunological Responses to SARS-CoV-2

COVID-19 in Children and Vitamin D

In December 2019, the so-called "coronavirus disease 2019" (COVID-19) began. This disease is characterized by heterogeneous clinical manifestations, ranging from an asymptomatic process to life-threatening conditions associated with a "cytokine storm". This article (narrative review) summarizes the epidemiologic characteristics and clinical manifestations of COVID-19 and multi-system inflammatory syndrome in children (MIS-C). The effect of the pandemic confinement on vitamin D status and the hypotheses proposed to explain the age-related difference in the severity of COVID-19 are discussed. The role of vitamin D as a critical regulator of both innate and adaptive immune responses and the COVID-19 cytokine storm is analyzed. Vitamin D and its links to both COVID-19 (low levels of vitamin D appear to worsen COVID-19 outcomes) and the cytokine storm (anti-inflammatory activity) are detailed. Finally, the efficacy of vitamin D supplementation in COVID-19 is evaluated, but the evidence supporting vitamin D supplementation as an adjuvant treatment for COVID-19 remains uncertain.

Unravelling demographic and socioeconomic patterns of COVID-19 death and other causes of death: results of an individual-level analysis of exhaustive cause of death data in Belgium, 2020

BACKGROUND

The COVID-19 pandemic led to significant excess mortality in 2020 in Belgium. By using microlevel cause-specific mortality data for the total adult population in Belgium in 2020, three outcomes were considered in this study aiming at predicting sociodemographic (SD) and socioeconomic (SE) patterns of (1) COVID-19 specific death compared to survival; (2) all other causes of death (OCOD) compared to survival; and (3) COVID-19 specific death compared to all OCOD.

METHODS

Two complementary statistical methods were used. First, multivariable logistic regression models providing odds ratios and 95% confidence intervals were fitted for the three study outcomes. In addition, we computed conditional inference tree (CIT) algorithms, a non-parametric class of classification trees, to identify and rank by significance level the strongest predictors of the three study outcomes.

RESULTS

Older individuals, males, individuals living in collectivities, first-generation migrants, and deprived SE groups experienced higher odds of dying from COVID-19 compared to survival; living in collectivities was identified by the CIT as the strongest predictor followed by age and sex. Education emerged as one of the strongest predictors for individuals not living in collectivities. Overall, similar patterns were observed for all OCOD except for first- and second-generation migrants having lower odds of all OCOD compared to survival; age group was identified by the CIT as the strongest predictor. Older individuals, males, individuals living in collectivities, first- and second-generation migrants, and individuals with lower levels of education had higher odds of COVID-19 death compared to all OCOD; living in collectivities was identified by the CIT as the strongest predictor followed by age, sex, and migration background. Education and income emerged as among the strongest predictors among individuals not living in collectivities.

CONCLUSIONS

This study identified important SD and SE disparities in COVID-19 mortality, with living in collectivities highlighted as the strongest predictor. This underlines the importance of implementing preventive measures, particularly within the most vulnerable populations, in infectious disease pandemic preparedness to reduce virus circulation and the resulting lethality.

Promising Strategies to Reduce the SARS-CoV-2 Amyloid Deposition in the Brain and Prevent COVID-19-Exacerbated Dementia and Alzheimer's Disease

The COVID-19 pandemic, caused by infection with the SARS-CoV-2 virus, is associated with cognitive impairment and Alzheimer's disease (AD) progression. Once it enters the brain, the SARS-CoV-2 virus stimulates accumulation of amyloids in the brain that are highly toxic to neural cells. These amyloids may trigger neurological symptoms in COVID-19. The meningeal lymphatic vessels (MLVs) play an important role in removal of toxins and mediate viral drainage from the brain. MLVs are considered a promising target to prevent COVID-19-exacerbated dementia. However, there are limited methods for augmentation of MLV function. This review highlights new discoveries in the field of COVID-19-mediated amyloid accumulation in the brain associated with the neurological symptoms and the development of promising strategies to stimulate clearance of amyloids from the brain through lymphatic and other pathways. These strategies are based on innovative methods of treating brain dysfunction induced by COVID-19 infection, including the use of photobiomodulation, plasmalogens, and medicinal herbs, which offer hope for addressing the challenges posed by the SARS-CoV-2 virus.

Guidance for prevention and management of COVID-19 in children and adolescents: A consensus statement from the Pediatric Infectious Diseases Society Pediatric COVID-19 Therapies Taskforce

BACKGROUND

Since November 2019, the SARS-CoV-2 pandemic has created challenges for preventing and managing COVID-19 in children and adolescents. Most research to develop new therapeutic interventions or to repurpose existing ones has been undertaken in adults, and although most cases of infection in pediatric populations are mild, there have been many cases of critical and fatal infection. Understanding the risk factors for severe illness and the evidence for safety, efficacy, and effectiveness of therapies for COVID-19 in children is necessary to optimize therapy.

METHODS

A panel of experts in pediatric infectious diseases, pediatric infectious diseases pharmacology, and pediatric intensive care medicine from 21 geographically diverse North American institutions was re-convened. Through a series of teleconferences and web-based surveys and a systematic review with meta-analysis of data for risk factors, a guidance statement comprising a series of recommendations for risk stratification, treatment, and prevention of COVID-19 was developed and refined based on expert consensus.

RESULTS

There are identifiable clinical characteristics that enable risk stratification for patients at risk for severe COVID-19. These risk factors can be used to guide the treatment of hospitalized and non-hospitalized children and adolescents with COVID-19 and to guide preventative therapy where options remain available.

Antiviral and Anti-Inflammatory Therapeutic Effect of RAGE-Ig Protein against Multiple SARS-CoV-2 Variants of Concern Demonstrated in K18-hACE2 Mouse and Syrian Golden Hamster Models

SARS-CoV-2 variants of concern (VOCs) continue to evolve and reemerge with chronic inflammatory long COVID sequelae, necessitating the development of anti-inflammatory therapeutic molecules. Therapeutic effects of the receptor for advanced glycation end products (RAGE) were reported in many inflammatory diseases. However, a therapeutic effect of RAGE in COVID-19 has not been reported. In the present study, we investigated whether and how the RAGE-Ig fusion protein would have an antiviral and anti-inflammatory therapeutic effect in the COVID-19 system. The protective therapeutic effect of RAGE-Ig was determined in vivo in K18-hACE2 transgenic mice and Syrian golden hamsters infected with six VOCs of SARS-CoV-2. The underlying antiviral mechanism of RAGE-Ig was determined in vitro in SARS-CoV-2-infected human lung epithelial cells (BEAS-2B). Following treatment of K18-hACE2 mice and hamsters infected with various SARS-CoV-2 VOCs with RAGE-Ig, we demonstrated (1) significant dose-dependent protection (i.e., greater survival, less weight loss, lower virus replication in the lungs); (2) a reduction of inflammatory macrophages (F4/80+/Ly6C+) and neutrophils (CD11b+/Ly6G+) infiltrating the infected lungs; (3) a RAGE-Ig dose-dependent increase in the expression of type I IFNs (IFN-α and IFN-β) and type III IFN (IFNλ2) and a decrease in the inflammatory cytokines (IL-6 and IL-8) in SARS-CoV-2-infected human lung epithelial cells; and (4) a dose-dependent decrease in the expression of CD64 (FcgR1) on monocytes and lung epithelial cells from symptomatic COVID-19 patients. Our preclinical findings revealed type I and III IFN-mediated antiviral and anti-inflammatory therapeutic effects of RAGE-Ig protein against COVID-19 caused by multiple SARS-CoV-2 VOCs.

Characteristics of innate, humoral and cellular immunity in children with non-severe SARS-CoV-2 infection

The symptoms of children infected with SARS-CoV-2 are mainly asymptomatic, mild, moderate, and a few severe cases. To understand the immune response characteristics of children infected with SARS-COV-2 who do not develop severe cases, 82 children infected with the SARS-CoV-2 delta strain were recruited in this study. Our results showed that high levels of IgG, IgM, and neutralization antibodies appeared in children infected with SARS-CoV-2. SARS-CoV-2 induced upregulation of both pro-inflammatory factors including TNF-α and anti-inflammatory factors including IL-4 and IL-13 in the children, even IL-10. The expression of INF-α in infected children also showed a significant increase compared to healthy children. However, IL-6, one of the important inflammatory factors, did not show an increase in infected children. It is worth noting that a large number of chemokines reduced in the SARS-CoV-2-infected children. Subsequently, TCR Repertoire, TCRβ bias, and preferential usage were analyzed on data of TCR next-generation sequencing from 8 SARS-CoV-2-infected children and 8 healthy controls. We found a significant decrease in TCR clonal diversity and a significant increase in TCR clonal expansion in SARS-CoV-2-infected children compared to healthy children. The most frequent V and J genes in SARS-CoV-2 children were TRBV28 and TRBJ2-1. The most frequently VβJ gene pairing in SARS-CoV-2 infected children was TRBV20-1-TRBJ2-1. The strong antiviral antibody levels, low expression of key pro-inflammatory factors, significant elevation of anti-inflammatory factors, and downregulation of many chemokines jointly determine that SARS-CoV-2-infected children rarely develop severe cases. Overall, our findings shed a light on the immune response of non-severe children infected with SARS-CoV-2.

Elucidating systemic immune responses to acute and convalescent SARS-CoV-2 infection in children and elderly individuals

BACKGROUND

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), a causative pathogen of the COVID-19 pandemic, affects all age groups. However, various studies have shown that COVID-19 presentation and severity vary considerably with age. We, therefore, wanted to examine the differences between the immune responses of children with COVID-19 and elderly COVID-19 individuals.

METHODS

We analyzed cytokines, chemokines, growth factors, and acute phase proteins in acute and convalescent COVID-19 children and the elderly with acute and convalescent COVID-19.

RESULTS

We show that most of the pro-inflammatory cytokines (interferon [IFN]γ, interleukin [IL]-2, tumor necrosis factor-α [TNFα], IL-1α, IFNα, IFNβ, IL-6, IL-12, IL-3, IL-7, IL-1Ra, IL-13, and IL-10), chemokines (CCL4, CCL11, CCL19, CXCL1, CXCL2, CXCL8, and CXL10), growth factors (vascular endothelial growth factor and CD40L) and acute phase proteins (C-reactive protein, serum amyloid P, and haptoglobin) were decreased in children with acute COVID 19 as compared with elderly individuals. In contrast, children with acute COVID-19 exhibited elevated levels of cytokines- IL-1β, IL-33, IL-4, IL-5, and IL-25, growth factors-fibroblast growth factor-2, platelet- derived growth factors-BB, and transforming growth factorα as compared with elderly individuals. Similar, differences were manifest in children and elderly with convalescent COVID-19.

CONCLUSION

Thus, COVID-19 children are characterized by distinct cytokine/chemokine/growth factor/acute phase protein markers that are markedly different from elderly COVID-19 individuals.

Immunological and biochemical biomarker alterations among SARS-COV-2 patients with varying disease phenotypes in Uganda

Every novel infection requires an assessment of the host response coupled with identification of unique biomarkers for predicting disease pathogenesis, treatment targets and diagnostic utility. Studies have exposed dysregulated inflammatory response induced by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as significant predictor or cause of disease severity/prognosis and death. This study evaluated inflammatory biomarkers induced by SARS-CoV-2 in plasma of patients with varying disease phenotypes and healthy controls with prognostic or therapeutic potential. We stratified SARS-CoV-2 plasma samples based on disease status (asymptomatic, mild, severe, and healthy controls), as diagnosed by RT-PCR SARS-CoV-2. We used a solid phase sandwich and competitive Enzyme-Linked Immunosorbent Assay (ELISA) to measure levels of panels of immunological (IFN-γ, TNF-α, IL-6, and IL-10) and biochemical markers (Ferritin, Procalcitonin, C-Reactive Protein, Angiotensin II, Homocysteine, and D-dimer). Biomarker levels were compared across SARS-CoV-2 disease stratification. Plasma IFN-γ, TNF-α, IL-6, and IL-10 levels were significantly (P < 0.05) elevated in the severe SARS-CoV-2 patients as compared to mild, asymptomatic, and healthy controls. Ferritin, Homocysteine, and D-dimer plasma levels were significantly elevated in severe cases over asymptomatic and healthy controls. Plasma C-reactive protein and Angiotensin II levels were significantly (P < 0.05) higher in mild than severe cases and healthy controls. Plasma Procalcitonin levels were significantly higher in asymptomatic than in mild, severe cases and healthy controls. Our study demonstrates the role of host inflammatory biomarkers in modulating the pathogenesis of COVID-19. The study proposes a number of potential biomarkers that could be explored as SARS-CoV-2 treatment targets and possible prognostic predictors for a severe outcome. The comprehensive analysis of prognostic biomarkers may contribute to the evidence-based management of COVID-19 patients.

Age-related influence on DNA damage, proteomic inflammatory markers and oxidative stress in hospitalized COVID-19 patients compared to healthy controls

COVID-19 infections are accompanied by adverse changes in inflammatory pathways that are also partly influenced by increased oxidative stress and might result in elevated DNA damage. The aim of this case-control study was to examine whether COVID-19 patients show differences in oxidative stress-related markers, unconjugated bilirubin (UCB), an inflammation panel and DNA damage compared to healthy, age-and sex-matched controls. The Comet assay with and without the treatment of formamidopyrimidine DNA glycosylase (FPG) and H2O2 challenge was used to detect DNA damage in whole blood. qPCR was applied for gene expression, UCB was analyzed via HPLC, targeted proteomics were applied using Olink® inflammation panel and various oxidative stress as well as clinical biochemistry markers were analyzed in plasma. Hospitalized COVID-19 patients (n = 48) demonstrated higher serum levels of 55 inflammatory proteins (p < 0.001), including hs-C-reactive protein levels (p < 0.05), compared to healthy controls (n = 48). Interestingly, significantly increased age-related DNA damage (%-DNA in tail) after formamidopyrimidine DNA glycosylase (FPG) treatment was measured in younger (n = 24, average age 55.7 years; p < 0.05) but not in older COVID-19 patients (n = 24, average age 83.5 years; p > 0.05). Although various oxidative stress markers were not altered (e.g., FRAP, malondialdehyde, p > 0.05), a significant increased ratio of oxidized to reduced glutathione was detected in COVID-19 patients compared to healthy controls (p < 0.05). UCB levels were significantly lower in individuals with COVID-19, especially in younger COVID-19 patients (p < 0.05). These results suggest that COVID-19 infections exert effects on DNA damage related to age in hospitalized COVID-19 patients that might be driven by changes in inflammatory pathways but are not altered by oxidative stress parameters.

Rapid Triage of Children with Suspected COVID-19 Using Laboratory-Based Machine-Learning Algorithms

In order to limit the spread of the novel betacoronavirus (SARS-CoV-2), it is necessary to detect positive cases as soon as possible and isolate them. For this purpose, machine-learning algorithms, as a field of artificial intelligence, have been recognized as a promising tool. The aim of this study was to assess the utility of the most common machine-learning algorithms in the rapid triage of children with suspected COVID-19 using easily accessible and inexpensive laboratory parameters. A cross-sectional study was conducted on 566 children treated for respiratory diseases: 280 children with PCR-confirmed SARS-CoV-2 infection and 286 children with respiratory symptoms who were SARS-CoV-2 PCR-negative (control group). Six machine-learning algorithms, based on the blood laboratory data, were tested: random forest, support vector machine, linear discriminant analysis, artificial neural network, k-nearest neighbors, and decision tree. The training set was validated through stratified cross-validation, while the performance of each algorithm was confirmed by an independent test set. Random forest and support vector machine models demonstrated the highest accuracy of 85% and 82.1%, respectively. The models demonstrated better sensitivity than specificity and better negative predictive value than positive predictive value. The F1 score was higher for the random forest than for the support vector machine model, 85.2% and 82.3%, respectively. This study might have significant clinical applications, helping healthcare providers identify children with COVID-19 in the early stage, prior to PCR and/or antigen testing. Additionally, machine-learning algorithms could improve overall testing efficiency with no extra costs for the healthcare facility.

Safety and immunogenicity of an AS03-adjuvanted plant-based SARS-CoV-2 vaccine in Adults with and without Comorbidities

The rapid spread of SARS-CoV-2 continues to impact humanity on a global scale with rising total morbidity and mortality. Despite the development of several effective vaccines, new products are needed to supply ongoing demand and to fight variants. We report herein a pre-specified interim analysis of the phase 2 portion of a Phase 2/3, randomized, placebo-controlled trial of a coronavirus virus-like particle (CoVLP) vaccine candidate, produced in plants that displays the SARS-CoV-2 spike glycoprotein, adjuvanted with AS03 (NCT04636697). A total of 753 participants were recruited between 25th November 2020 and 24th March 2021 into three groups: Healthy Adults (18-64 years: N = 306), Older Adults (≥65 years: N = 282) and Adults with Comorbidities (≥18 years: N = 165) and randomized 5:1 to receive two intramuscular doses of either vaccine (3.75 µg CoVLP/dose+AS03) or placebo, 21 days apart. This report presents safety, tolerability and immunogenicity data up to 6 months post-vaccination. The immune outcomes presented include neutralizing antibody (NAb) titres as measured by pseudovirion assay at days 21 and 42 as well as neutralizing antibody cross-reactivity to several variants of concern (VOCs): Alpha, Beta, Gamma, Delta, and Omicron (BA.1), up to 201 days post-immunization. Cellular (IFN-γ and IL-4 ELISpot) response data in day 21 and 42 peripheral blood are also presented. In this study, CoVLP+AS03 was well-tolerated and adverse events (AE) after each dose were generally mild to moderate and transient. Solicited AEs in Older Adults and Adults with Comorbidities were generally less frequent than in Healthy Adults and the reactogenicity was higher after the second dose. CoVLP+AS03 induced seroconversion in >35% of participants in each group after the first dose and in ~98% of participants, 21 days after the second dose. In all cohorts, 21-days after the second dose, NAb levels in sera against the vaccine strain were ~10-times those in a panel of convalescent sera. Cross-reactivity to Alpha, Beta and Delta variants was generally retained to day 201 (>80%) while cross-reactivity to the Gamma variant was reduced but still substantial at day 201 (73%). Cross-reactivity to the Omicron variant fell from 72% at day 42 to 20% at day 201. Almost all participants in all groups (>88%) had detectable cellular responses (IFN-γ, IL-4 or both) at 21 days after the second dose. A Th1-biased response was most evident after the first dose and was still present after the second dose. These data demonstrated that CoVLP+AS03 is well-tolerated and highly immunogenic, generating a durable (at least 6 months) immune response against different VOCs, in adults ≥18 years of age, with and without comorbidities.

The Remarkable Roles of the Receptor for Advanced Glycation End Products (RAGE) and Its Soluble Isoforms in COVID-19: The Importance of RAGE Pathway in the Lung Injuries

The respiratory symptoms of acute respiratory distress syndrome (ARDS) in the coronavirus disease 2019 (COVID-19) patients is associated with accumulation of pre-inflammatory molecules such as advanced glycation end-products (AGES), calprotectin, high mobility group box family-1 (HMGB1), cytokines, angiotensin converting enzyme 2 (ACE2), and other molecules in the alveolar space of lungs and plasma. The receptor for advanced glycation end products (RAGEs), which is mediated by the mitogen-activated protein kinase (MAPK), plays a critical role in the severity of chronic inflammatory diseases such as diabetes mellitus (DM) and ARDS. The RAGE gene is most expressed in the alveolar epithelial cells (AECs) of the pulmonary system. Several clinical trials are now being conducted to determine the possible association between the levels of soluble isoforms of RAGE (sRAGE and esRAGE) and the severity of the disease in patients with ARDS and acute lung injury (ALI). In the current article, we reviewed the most recent studies on the RAGE/ligands axis and sRAGE/esRAGE levels in acute respiratory illness, with a focus on COVID-19–associated ARDS (CARDS) patients. According to the research conducted so far, sRAGE/esRAGE measurements in patients with CARDS can be used as a powerful chemical indicator among other biomarkers for assessment of early pulmonary involvement. Furthermore, inhibiting RAGE/MAPK and Angiotensin II receptor type 1 (ATR1) in CARDS patients can be a powerful strategy for diminishing cytokine storm and severe respiratory symptoms.

A multicompartment mathematical model based on host immunity for dissecting COVID-19 heterogeneity

The determinants underlying the heterogeneity of coronavirus disease 2019 (COVID-19) remain to be elucidated. To systemically analyze the immunopathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we built a multicompartment mathematical model based on immunological principles and typical COVID-19-related characteristics. This model integrated the trafficking of immune cells and cytokines among the secondary lymphoid organs, peripheral blood and lungs. Our results suggested that early-stage lymphopenia was related to lymphocyte chemotaxis, while prolonged lymphopenia in critically ill patients was associated with myeloid-derived suppressor cells. Furthermore, our model predicted that insufficient SARS-CoV-2-specific naïve T/B cell pools and ineffective activation of antigen-presenting cells (APCs) would cause delayed immunity activation, resulting in elevated viral load, low immunoglobulin level, etc. Overall, we provided a comprehensive view of the dynamics of host immunity after SARS-CoV-2 infection that enabled us to understand COVID-19 heterogeneity from systemic perspective.

Multiple Routes of Antibody-Dependent Enhancement of SARS-CoV-2 Infection

Antibody-dependent enhancement (ADE) of infection is generally known for many viruses. A potential risk of ADE in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has also been discussed since the beginning of the coronavirus disease 2019 (COVID-19) pandemic; however, clinical evidence of the presence of antibodies with ADE potential is limited. Here, we show that ADE antibodies are produced by SARS-CoV-2 infection and the ADE process can be mediated by at least two different host factors, Fcγ receptor (FcγR) and complement component C1q. Of 89 serum samples collected from acute or convalescent COVID-19 patients, 62.9% were found to be positive for SARS-CoV-2-specific IgG. FcγR- and/or C1q-mediated ADE were detected in 50% of the IgG-positive sera, whereas most of them showed neutralizing activity in the absence of FcγR and C1q. Importantly, ADE antibodies were found in 41.4% of the acute COVID-19 patients. Neutralizing activity was also detected in most of the IgG-positive sera, but it was counteracted by ADE in subneutralizing conditions in the presence of FcγR or C1q. Although the clinical importance of ADE needs to be further investigated with larger numbers of COVID-19 patient samples, our data suggest that SARS-CoV-2 utilizes multiple mechanisms of ADE. C1q-mediated ADE may particularly have a clinical impact since C1q is present at high concentrations in plasma and its receptors are ubiquitously expressed on the surfaces of many types of cells, including respiratory epithelial cells, which SARS-CoV-2 primarily infects.

IMPORTANCE Potential risks of antibody-dependent enhancement (ADE) in the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been discussed and the proposed mechanism mostly depends on the Fc gamma receptor (FcγR). However, since FcγRs are exclusively expressed on immune cells, which are not primary targets of SARS-CoV-2, the clinical importance of ADE of SARS-CoV-2 infection remains controversial. Our study demonstrates that SARS-CoV-2 infection induces antibodies that increase SARS-CoV-2 infection through another ADE mechanism in which complement component C1q mediates the enhancement. Although neutralizing activity was also detected in the serum samples, it was counteracted by ADE in the presence of FcγR or C1q. Considering the ubiquity of C1q and its cellular receptors, C1q-mediated ADE may more likely occur in respiratory epithelial cells, which SARS-CoV-2 primarily infects. Our data highlight the importance of careful monitoring of the antibody properties in COVID-19 convalescent and vaccinated individuals.

Autoantibodies Against Proteins Previously Associated With Autoimmunity in Adult and Pediatric Patients With COVID-19 and Children With MIS-C

The antibody profile against autoantigens previously associated with autoimmune diseases and other human proteins in patients with COVID-19 or multisystem inflammatory syndrome in children (MIS-C) remains poorly defined. Here we show that 30% of adults with COVID-19 had autoantibodies against the lung antigen KCNRG, and 34% had antibodies to the SLE-associated Smith-D3 protein. Children with COVID-19 rarely had autoantibodies; one of 59 children had GAD65 autoantibodies associated with acute onset of insulin-dependent diabetes. While autoantibodies associated with SLE/Sjögren's syndrome (Ro52, Ro60, and La) and/or autoimmune gastritis (gastric ATPase) were detected in 74% (40/54) of MIS-C patients, further analysis of these patients and of children with Kawasaki disease (KD), showed that the administration of intravenous immunoglobulin (IVIG) was largely responsible for detection of these autoantibodies in both groups of patients. Monitoring in vivo decay of the autoantibodies in MIS-C children showed that the IVIG-derived Ro52, Ro60, and La autoantibodies declined to undetectable levels by 45-60 days, but gastric ATPase autoantibodies declined more slowly requiring >100 days until undetectable. Further testing of IgG and/or IgA antibodies against a subset of potential targets identified by published autoantigen array studies of MIS-C failed to detect autoantibodies against most (16/18) of these proteins in patients with MIS-C who had not received IVIG. However, Troponin C2 and KLHL12 autoantibodies were detected in 2 of 20 and 1 of 20 patients with MIS-C, respectively. Overall, these results suggest that IVIG therapy may be a confounding factor in autoantibody measurements in MIS-C and that antibodies against antigens associated with autoimmune diseases or other human proteins are uncommon in MIS-C.

Plasma proteomic and metabolomic characterization of COVID-19 survivors 6 months after discharge

Coronavirus disease 2019 (COVID-19) has gained prominence as a global pandemic. Studies have suggested that systemic alterations persist in a considerable proportion of COVID-19 patients after hospital discharge. We used proteomic and metabolomic approaches to analyze plasma samples obtained from 30 healthy subjects and 54 COVID-19 survivors 6 months after discharge from the hospital, including 30 non-severe and 24 severe patients. Through this analysis, we identified 1019 proteins and 1091 metabolites. The differentially expressed proteins and metabolites were then subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Among the patients evaluated, 41% of COVID-19 survivors reported at least one clinical symptom and 26.5% showed lung imaging abnormalities at 6 months after discharge. Plasma proteomics and metabolomics analysis showed that COVID-19 survivors differed from healthy control subjects in terms of the extracellular matrix, immune response, and hemostasis pathways. COVID-19 survivors also exhibited abnormal lipid metabolism, disordered immune response, and changes in pulmonary fibrosis-related proteins. COVID-19 survivors show persistent proteomic and metabolomic abnormalities 6 months after discharge from the hospital. Hence, the recovery period for COVID-19 survivors may be longer.

Oxidative Stress-Related Mechanisms in SARS-CoV-2 Infections

The COVID-19 pandemic caused relatively high mortality in patients, especially in those with concomitant diseases (i.e., diabetes, hypertension, and chronic obstructive pulmonary disease (COPD)). In most of aforementioned comorbidities, the oxidative stress appears to be an important player in their pathogenesis. The direct cause of death in critically ill patients with COVID-19 is still far from being elucidated. Although some preliminary data suggests that the lung vasculature injury and the loss of the functioning part of pulmonary alveolar population are crucial, the precise mechanism is still unclear. On the other hand, at least two classes of medications used with some clinical benefits in COVID-19 treatment seem to have a major influence on ROS (reactive oxygen species) and RNS (reactive nitrogen species) production. However, oxidative stress is one of the important mechanisms in the antiviral immune response and innate immunity. Therefore, it would be of interest to summarize the data regarding the oxidative stress in severe COVID-19. In this review, we discuss the role of oxidative and antioxidant mechanisms in severe COVID-19 based on available studies. We also present the role of ROS and RNS in other viral infections in humans and in animal models. Although reactive oxygen and nitrogen species play an important role in the innate antiviral immune response, in some situations, they might have a deleterious effect, e.g., in some coronaviral infections. The understanding of the redox mechanisms in severe COVID-19 disease may have an impact on its treatment.

Low levels of CIITA and high levels of SOCS1 predict COVID-19 disease severity in children and adults

It is unclear why COVID-19 ranges from asymptomatic to severe. When SARS-CoV-2 is detected, interferon (IFN) response is activated. When it is insufficient or delayed, it might lead to overproduction of cytokines and severe COVID-19. The aim was to compare cytokine and IFN patterns in children and adults with differing severity with SARS-CoV-2.It was a prospective, observational study, including 84 patients. Patients with moderate/severe disease had higher cytokines' values than patients with mild disease (p< 0.001).Two IFN genes were selected to build a decision tree for severity classification: SOCS1 (representative of the rest of the IFN genes) and CIITA (inverse correlation). Low values of CIITA and high values of SOCS1 indicated severe disease. This method correctly classified 33/38(86.8%) of children and 27/34 (79.4%) of adults. To conclude, patients with severe disease had an elevated cytokine pattern, which correlated with the IFN response, with low CIITA and high SOCS1 values.

Evaluation of Clinical and Immune Responses in Recovered Children with Mild COVID-19

The coronavirus disease 2019 (COVID-19) has spread globally and variants continue to emerge, with children are accounting for a growing share of COVID-19 cases. However, the establishment of immune memory and the long-term health consequences in asymptomatic or mildly symptomatic children after severe acute respiratory syndrome coronavirus 2 infection are not fully understood. We collected clinical data and whole blood samples from discharged children for 6–8 months after symptom onset among 0-to-14-year-old children. Representative inflammation signs returned to normal in all age ranges. The infants and young children (0–4 years old) had lung lesions that persisted for 6–8 months and were less responsive for antigen-specific IgG secretion. In the 5-to-14-year-old group, lung imaging abnormalities gradually recovered, and the IgG-specific antibody response was strongest. In addition, we found a robust IgM⁺ memory B cell response in all age. Memory T cells specific for the spike or nucleocapsid protein were generated, with no significant difference in IFN-γ response among all ages. Our study highlights that although lung lesions caused by COVID-19 can last for at least 6–8 months in infants and young children, most children have detectable residual neutralizing antibodies and specific cellular immune responses at this stage.

Acute Vision Loss and Conjunctival Hemorrhage as Telltale Symptoms of PIMS-TS

There is a global concern about children presenting with inflammatory syndrome with variable clinical features during the ongoing COVID-19 pandemic. This paper reports the first pediatric case of bilateral serous retinal detachment and conjunctival hemorrhage as a revealing pattern of the pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS). Despite the severity of multisystemic involvement, the management with steroids was very successful. Complete remission was obtained within 3 months of acute onset.

A clinical-statistical study on COVID-19 infection and death status at the Alshifaa Healthcare Center/ Baghdad

Background: COVID-19 is an ongoing disease that caused, and still causes, many challenges for humanity. In fact, COVID-19 death cases reached more than 4.5 million by the end of August 2021, although an improvement in the medical treatments and pharmaceutical protocols was obtained, and many vaccines were released. Objective: To, statistically, analyze the data of COVID-19 patients at Alshifaa Healthcare Center (Baghdad, Iraq). Methods: In this work, a statistical analysis was conducted on data included the total number, positive cases, and negative cases of people tested for COVID-19 at the Alshifaa Healthcare Center/Baghdad for the period 1 September – 31 December 2020. The number of people who got the test was 1080, where 424 were infected and the rest of them were not. Results: The study showed that males’ infection and death cases were higher than females by more than double, despite the population ratios of the two genders being almost equal. Furthermore, as the age of patients is older, the chance of death is higher. Death cases were lower in December than the previous three months, which could be attributed to lower infection cases compared with the previous months. Conclusions: We can conclude that the peak of infected ages was the same as the other countries. Hence, the number of checked children was low, while we have the peak around the 40s and 50s. Females’ death cases were much less than males, which could be attributed to the genetic influence and the higher responsibility that females showed than males to prevent the disease’s spreading.

Persistence of the SARS-CoV-2 Antibody Response in Asymptomatic Patients in Correctional Facilities

SARS-CoV-2 has caused a global health disaster with millions of death worldwide, and the substantial proportion of asymptomatic carriers poses a huge threat to public health. The long-term antibody responses and neutralization activity during natural asymptomatic SARS-CoV-2 infection are unknown. In this study, we used enzyme-linked immunosorbent assays (ELISA) and neutralization assay with purified SARS-CoV-2S and N proteins to study the antibody responses of 156 individuals with natural asymptomatic infection. We found robust antibody responses to SARS-CoV-2 in 156 patients from 6 to 12 months. Although the antibody responses gradually decreased, S-IgG was more stable than N-IgG. S-IgG was still detected in 79% of naturally infected individuals after 12 months of infection. Moderate to potent neutralization activities were also observed in 98.74% of patients 6 months after infection. However, this proportion decreased at 8-month (46.15%) and 10-month (39.11%) after infection, respectively. Only 23.72% of patients displayed potent neutralization activity at 12 months. This study strongly supports the long-term presence of antibodies against SARS-CoV-2 in individuals with natural asymptomatic infection, although the magnitude of the antibody responses started to cripple 6 months after infection.

Estimated US Infection- and Vaccine-Induced SARS-CoV-2 Seroprevalence Based on Blood Donations, July 2020-May 2021

IMPORTANCE

People who have been infected with or vaccinated against SARS-CoV-2 have reduced risk of subsequent infection, but the proportion of people in the US with SARS-CoV-2 antibodies from infection or vaccination is uncertain.

OBJECTIVE

To estimate trends in SARS-CoV-2 seroprevalence related to infection and vaccination in the US population.

DESIGN, SETTING, AND PARTICIPANTS

In a repeated cross-sectional study conducted each month during July 2020 through May 2021, 17 blood collection organizations with blood donations from all 50 US states; Washington, DC; and Puerto Rico were organized into 66 study-specific regions, representing a catchment of 74% of the US population. For each study region, specimens from a median of approximately 2000 blood donors were selected and tested each month; a total of 1 594 363 specimens were initially selected and tested. The final date of blood donation collection was May 31, 2021.

EXPOSURE

Calendar time.

MAIN OUTCOMES AND MEASURES

Proportion of persons with detectable SARS-CoV-2 spike and nucleocapsid antibodies. Seroprevalence was weighted for demographic differences between the blood donor sample and general population. Infection-induced seroprevalence was defined as the prevalence of the population with both spike and nucleocapsid antibodies. Combined infection- and vaccination-induced seroprevalence was defined as the prevalence of the population with spike antibodies. The seroprevalence estimates were compared with cumulative COVID-19 case report incidence rates.

RESULTS

Among 1 443 519 specimens included, 733 052 (50.8%) were from women, 174 842 (12.1%) were from persons aged 16 to 29 years, 292 258 (20.2%) were from persons aged 65 years and older, 36 654 (2.5%) were from non-Hispanic Black persons, and 88 773 (6.1%) were from Hispanic persons. The overall infection-induced SARS-CoV-2 seroprevalence estimate increased from 3.5% (95% CI, 3.2%-3.8%) in July 2020 to 20.2% (95% CI, 19.9%-20.6%) in May 2021; the combined infection- and vaccination-induced seroprevalence estimate in May 2021 was 83.3% (95% CI, 82.9%-83.7%). By May 2021, 2.1 SARS-CoV-2 infections (95% CI, 2.0-2.1) per reported COVID-19 case were estimated to have occurred.

CONCLUSIONS AND RELEVANCE

Based on a sample of blood donations in the US from July 2020 through May 2021, vaccine- and infection-induced SARS-CoV-2 seroprevalence increased over time and varied by age, race and ethnicity, and geographic region. Despite weighting to adjust for demographic differences, these findings from a national sample of blood donors may not be representative of the entire US population.

Robust innate responses to SARS-CoV-2 in children resolve faster than in adults without compromising adaptive immunity

SARS-CoV-2 infection in children is less severe than it is in adults. We perform a longitudinal analysis of the early innate responses in children and adults with mild infection within household clusters. Children display fewer symptoms than adults do, despite similar initial viral load, and mount a robust anti-viral immune signature typical of the SARS-CoV-2 infection and characterized by early interferon gene responses; increases in cytokines, such as CXCL10 and GM-CSF; and changes in blood cell numbers. When compared with adults, the antiviral response resolves faster (within a week of symptoms), monocytes and dendritic cells are more transiently activated, and genes associated with B cell activation appear earlier in children. Nonetheless, these differences do not have major effects on the quality of SARS-CoV-2-specific antibody responses. Our findings reveal that better early control of inflammation as observed in children may be key for rapidly controlling infection and limiting the disease course.

The Dynamics of B Cell Aging in Health and Disease

Aging is considered to be an important risk factor for several inflammatory diseases. B cells play a major role in chronic inflammatory diseases by antibody secretion, antigen presentation and T cell regulation. Different B cell subsets have been implicated in infections and multiple autoimmune diseases. Since aging decreases B cell numbers, affects B cell subsets and impairs antibody responses, the aged B cell is expected to have major impacts on the development and progression of these diseases. In this review, we summarize the role of B cells in health and disease settings, such as atherosclerotic disease. Furthermore, we provide an overview of age-related changes in B cell development and function with respect to their impact in chronic inflammatory diseases.

PM2.5, NO2, wildfires, and other environmental exposures are linked to higher Covid 19 incidence, severity, and death rates

Numerous studies have linked outdoor levels of PM_2.5, PM₁₀, NO₂, O₃, SO₂, and other air pollutants to significantly higher rates of Covid 19 morbidity and mortality, although the rate in which specific concentrations of pollutants increase Covid 19 morbidity and mortality varies widely by specific country and study. As little as a 1-μg/m³ increase in outdoor PM_2.5 is estimated to increase rates of Covid 19 by as much as 0.22 to 8%. Two California studies have strongly linked heavy wildfire burning periods with significantly higher outdoor levels of PM_2.5 and CO as well as significantly higher rates of Covid 19 cases and deaths. Active smoking has also been strongly linked significantly increased risk of Covid 19 severity and death. Other exposures possibly related to greater risk of Covid 19 morbidity and mortality include incense, pesticides, heavy metals, dust/sand, toxic waste sites, and volcanic emissions. The exact mechanisms in which air pollutants increase Covid 19 infections are not fully understood, but are probably related to pollutant-related oxidation and inflammation of the lungs and other tissues and to the pollutant-driven alternation of the angiotensin-converting enzyme 2 in respiratory and other cells.

The immune response to SARS-CoV-2 and COVID-19 immunopathology - Current perspectives

SARS-CoV-2 is a new beta coronavirus, similar to SARS-CoV-1, that emerged at the end of 2019 in the Hubei province of China. It is responsible for coronavirus disease 2019 (COVID-19), which was declared a pandemic by the World Health Organization on March 11, 2020. The ability to gain quick control of the pandemic has been hampered by a lack of detailed knowledge about SARS-CoV-2-host interactions, mainly in relation to viral biology and host immune response. The rapid clinical course seen in COVID-19 indicates that infection control in asymptomatic patients or patients with mild disease is probably due to the innate immune response, as, considering that SARS-CoV-2 is new to humans, an effective adaptive response would not be expected to occur until approximately 2-3 weeks after contact with the virus. Antiviral innate immunity has humoral components (complement and coagulation-fibrinolysis systems, soluble proteins that recognize glycans on cell surface, interferons, chemokines, and naturally occurring antibodies) and cellular components (natural killer cells and other innate lymphocytes). Failure of this system would pave the way for uncontrolled viral replication in the airways and the mounting of an adaptive immune response, potentially amplified by an inflammatory cascade. Severe COVID-19 appears to be due not only to viral infection but also to a dysregulated immune and inflammatory response. In this paper, the authors review the most recent publications on the immunobiology of SARS-CoV-2, virus interactions with target cells, and host immune responses, and highlight possible associations between deficient innate and acquired immune responses and disease progression and mortality. Immunotherapeutic strategies targeting both the virus and dysfunctional immune responses are also addressed.

Sex and Gender Differences in Testing, Hospital Admission, Clinical Presentation, and Drivers of Severe Outcomes From COVID-19

BACKGROUND

Males experience increased severity of illness and mortality from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compared with females, but the mechanisms of male susceptibility are unclear.

METHODS

We performed a retrospective cohort analysis of SARS-CoV-2 testing and admission data at 5 hospitals in the Maryland/Washington DC area. Using age-stratified logistic regression models, we quantified the impact of male sex on the risk of the composite outcome of severe disease or death (World Health Organization score 5-8) and tested the impact of demographics, comorbidities, health behaviors, and laboratory inflammatory markers on the sex effect.

RESULTS

Among 213 175 SARS-CoV-2 tests, despite similar positivity rates, males in age strata between 18 and 74 years were more frequently hospitalized. For the 2626 hospitalized individuals, clinical inflammatory markers (interleukin-6, C-reactive protein, ferritin, absolute lymphocyte count, and neutrophil:lymphocyte ratio) were more favorable for females than males (P < .001). Among 18-49-year-olds, male sex carried a higher risk of severe outcomes, both early (odds ratio [OR], 3.01; 95% CI, 1.75 to 5.18) and at peak illness during hospitalization (OR, 2.58; 95% CI, 1.78 to 3.74). Despite multiple differences in demographics, presentation features, comorbidities, and health behaviors, these variables did not change the association of male sex with severe disease. Only clinical inflammatory marker values modified the sex effect, reducing the OR for severe outcomes in males aged 18-49 years to 1.81 (95% CI, 1.00 to 3.26) early and 1.39 (95% CI, 0.93 to 2.08) at peak illness.

CONCLUSIONS

Higher inflammatory laboratory test values were associated with increased risk of severe coronavirus disease 2019 for males. A sex-specific inflammatory response to SARS-CoV-2 infection may underlie the sex differences in outcomes.

An analysis of chronic kidney disease as a prognostic factor in pediatric cases of COVID-19

Advanced age is a risk factor for severe infection by acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Children, however, often present with milder manifestations of Coronavirus Disease 2019 (COVID-19). Associations have been found between COVID-19 and multisystem inflammatory syndrome in children (MIS-C). Patients with the latter condition present more severe involvement. Adults with comorbidities such as chronic kidney disease (CKD) are more severely affected. This narrative review aimed to look into whether CKD contributed to more severe involvement in pediatric patients with COVID-19. The studies included in this review did not report severe cases or deaths, and indicated that pediatric patients with CKD and previously healthy children recovered quickly from infection. However, some patients with MIS-C required hospitalization in intensive care units and a few died, although it was not possible to correlate MIS-C and CKD. Conversely, adults with CKD reportedly had increased risk of severe infection by SARS-CoV-2 and higher death rates. The discrepancies seen between age groups may be due to immune system and renin-angiotensin system differences, with more pronounced expression of ACE2 in children. Immunosuppressant therapy has not been related with positive or negative effects in individuals with COVID-19, although current recommendations establish decreases in the dosage of some medications. To sum up with, CKD was not associated with more severe involvement in children diagnosed with COVID-19. Studies enrolling larger populations are still required.

A family case of COVID-19 pneumonia with different chest CT features and duration of SARS-CoV-2 shedding: a case report from Japan

Coronavirus disease 2019 (COVID-19) pneumonia in children characteristically has a milder clinical presentation, with milder inflammatory biomarkers and radiological findings. Accumulating evidence indicates a difference in chest computed tomography (CT) features and duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding between children and adults. Here, we report a family case of COVID-19 pneumonia in which two brothers (age 14 years and 2 years) had different findings. On admission, the 2-year-old had few symptoms with no sign of pneumonia, whereas the older brother had presented with pneumonia on admission. Both were positive for SARS-CoV-2 infection on polymerase chain reaction. They both had obvious characteristic signs of COVID-19 pneumonia on chest CT. However, CT findings in the younger brother were non-specific and similar to other pneumonias. The older brother required longer treatment because of a longer shedding period of SARS-CoV-2 detected in nasopharyngeal samples. Both boys were discharged without complications. This family case suggests that the clinical features of COVID-19 pneumonia might differ between younger and older children.

Environmental Determinants of Coronavirus Disease 2019 (COVID-19)

Purpose for Review

Since the coronavirus SARS-CoV-2 outbreak in China in late 2019 turned into a global pandemic, numerous studies have reported associations between environmental factors, such as weather conditions and a range of air pollutants (particulate matter, nitrogen dioxide, ozone, etc.) and the first wave of COVID-19 cases. This review aims to offer a critical assessment of the role of environmental exposure risk factors on SARS-CoV-2 infections and COVID-19 disease severity.

Recent Findings

In this review, we provide a critical assessment of COVID-19 risk factors, identify gaps in our knowledge (e.g., indoor air pollution), and discuss methodological challenges of association and causation and the impact lockdowns had on air quality. In addition, we will draw attention to ethnic and socioeconomic factors driving viral transmission related to COVID-19. The complex role angiotensin-converting enzyme 2 (ACE2) plays in COVID-19 and future promising avenues of research are discussed.

Summary

To demonstrate causality, we stress the need for future epidemiologic studies integrating personal air pollution exposures, detailed clinical COVID-19 data, and a range of socioeconomic factors, as well as in vitro and in vivo mechanistic studies.

Single Cell Transcriptomic Re-analysis of Immune Cells in Bronchoalveolar Lavage Fluids Reveals the Correlation of B Cell Characteristics and Disease Severity of Patients with SARS-CoV-2 Infection

The coronavirus disease 2019 (COVID-19) pandemic (severe acute respiratory syndrome coronavirus 2) is a global infectious disease with rapid spread. Some patients have severe symptoms and clinical signs caused by an excessive inflammatory response, which increases the risk of mortality. In this study, we reanalyzed scRNA-seq data of cells from bronchoalveolar lavage fluids of patients with COVID-19 with mild and severe symptoms, focusing on Ab-producing cells. In patients with severe disease, B cells seemed to be more activated and expressed more immunoglobulin genes compared with cells from patients with mild disease, and macrophages expressed higher levels of the TNF superfamily member B-cell activating factor but not of APRIL (a proliferation-inducing ligand). In addition, macrophages from patients with severe disease had increased pro-inflammatory features and pathways associated with Fc receptor-mediated signaling, compared with patients with mild disease. CCR2-positive plasma cells accumulated in patients with severe disease, probably because of increased CCL2 expression on macrophages from patients with severe disease. Together, these results support the hypothesis that different characteristics of B cells might be associated with the severity of COVID-19 infection.

The receptor for advanced glycation end product (RAGE) pathway in COVID-19

INTRODUCTION

Coronavirus disease-2019 (COVID-19) with lung involvement frequently causes morbidity and mortality. Advanced age appears to be the most important risk factor. The receptor for advanced glycation end-product (RAGE) pathway is considered to play important roles in the physiological aging and pathogenesis of lung diseases. This study aimed to investigate the possible relationship between COVID-19 and RAGE pathway.

MATERIALS AND METHODS

This study included 23 asymptomatic patients and 35 patients with lung involvement who were diagnosed with COVID-19 as well as 22 healthy volunteers. Lung involvement was determined using computed tomography. Serum soluble-RAGE (sRAGE) levels were determined using enzyme-linked immunosorbent assay.

RESULTS

The sRAGE levels were significantly higher in the asymptomatic group than in the control group. Age, fibrinogen, C-reactive protein, and ferritin levels were higher and the sRAGE level was lower in the patients with lung involvement than in the asymptomatic patients.

CONCLUSIONS

In this study, patients with high sRAGE levels were younger and had asymptomatic COVID-19. Patients with low sRAGE levels were elderly patients with lung involvement, which indicates that the RAGE pathway plays an important role in the aggravation of COVID-19.

Analysis of the Behaviour of Immunoglobulin G Antibodies in Children and Adults Convalescing From Severe Acute Respiratory Syndrome-Coronavirus-2 Infection

The pandemic caused by SARS CoV-2 (COVID-19) has affected millions of people since 2020. There are clinical differences and in mortality between the adult and paediatric population. Recently, the immune response through the development of antibodies has gained relevance due to the risk of reinfection and vaccines' development. Objective: Was to compare the association of clinical history and the clinical presentation of the disease with the development of IgG antibodies against SARS-CoV-2 in paediatric and adult patients with a history of positive reverse transcriptase-polymerase chain reaction (RT-PCR) results. Methods: Cross-sectional observational study carried out in a Paediatric Hospital in Mexico City included patients under 18 years of age and health personnel with positive RT-PCR for COVID-19 comparing antibody expression. The development of specific IgG antibodies was measured, the presence of comorbidities, duration, and severity of symptoms was determined. Results: Sixty-one subjects (20 < 18 years and 41 > 18 years) were analysed. The median sample collection was 3 weeks. There were no differences in the expression of specific antibodies; no differences were shown according to the symptoms' severity. A positive correlation (r = 0.77) was demonstrated between the duration of symptoms and antibody levels. Conclusions: In conclusion, there is a clear association between the duration of the symptoms associated with SARS-CoV-2 infection and the IgG units generated in paediatric and adult patients convalescing from COVID-19.

A critical analysis of CTRI registered AYUSH studies for COVID- 19

Background

The COVID-19 pandemic has provided an opportune time to evaluate the efficacy of traditional medicine. Many clinical studies involving AYUSH systems are being initiated and registered with Clinical Trials Registry - India (CTRI) since last few months.

Objective

The present work is an analysis of different characteristics of these studies on the basis of available datasets.

Material and Methods

COVID-19 related clinical studies involving the healthcare systems of AYUSH, registered on CTRI between 1^st February 2020 and 24^th August 2020, were searched. They were analysed as per different characteristics such as registration month, study sites, aim, sample size, population, setting, sponsorship, intervention and comparators, duration & outcome measures.

Results

A total of 197 AYUSH studies were registered on CTRI of which majority (n = 113) were from Ayurveda, with another nine of them with an intra-AYUSH collaboration. The highest number of studies were registered in month of June (n = 57). Maximum study sites were in Maharashtra (n = 65). From the 197 total studies, only six were observational studies, with 191 being interventional studies. As an outcome, majority of the studies aimed at recovery (n = 112). Majority of studies (n = 105) were Government of India sponsored and proposed in AYUSH setting (n = 107). The proportion of comparative studies was more than single arm studies. Guduchi (Tinospora cordifolia) was the most frequently mentioned drug.

Conclusion

Our analysis revealed some interesting characteristics of the registered studies such as use of platform trial design, system specific criteria for assessment and personalized interventions. Though it was not possible to evaluate the quality of these studies in view of the limited dataset used for trial registration, we could notice variations in important characteristics like sample size, treatment arms, comparator used and study duration according to the primary aim of the studies. Overall, the present review underlines the formidable efforts of AYUSH sector in combating COVID-19 outbreak.

Perspective: Reducing SARS-CoV2 Infectivity and Its Associated Immunopathology

COVID-19 has become difficult to contain in our interconnected world. In this article, we discuss some approaches that could reduce the consequences of COVID-19. We elaborate upon the utility of camelid single-domain antibodies (sdAbs), also referred to as nanobodies, which are naturally poised to neutralize viruses without enhancing its infectivity. Smaller sized sdAbs can be easily selected using microbes or the subcellular organelle display methods and can neutralize SARS-CoV2 infectivity. We also discuss issues related to their production using scalable platforms. The favorable outcome of the infection is evident in patients when the inflammatory response is adequately curtailed. Therefore, we discuss approaches to mitigate hyperinflammatory reactions initiated by SARS-CoV2 but orchestrated by immune mediators.