Molecular mechanisms and epidemiology of COVID-19 from an allergist's perspective

A Mouse Model of Ovalbumin-Induced Airway Allergy Exhibits Altered Localization of SARS-CoV-2-Susceptible Cells in the Lungs, Which Reflects Omicron BA.5 Infection Dynamics, Viral Mutations, and Immunopathology

Asthma, an allergic disease of the airways, is a risk factor for severity of common respiratory viral infections; however, the relationship between asthma and severity in COVID-19 remains unclear. Here, we examined the effects of SARS-CoV-2 (Omicron BA.5 strain) infection in a mouse model of airway allergy. First, stimulation of allergic mice with OVA resulted in the appearance of ACE2-negative mucus-secreting goblet cells in the bronchiolar region, and an increase in the number of ACE2-expressing cells in the alveoli. As a result, ACE2-expressing cells, which are susceptible to SARS-CoV-2, were limited to the distal portion of the bronchioles while they increased in the alveolar area. After viral infection, the peak infectious viral load in the OVA group was 100-fold lower than that in the phosphate buffered saline (PBS) group; however, clearance of viral RNA from the upper/lower airways was delayed. There were notable differences in acquisition of nsp5 and nsp6 mutations by the Omicron BA.5 strain recovered from BALF samples obtained from the OVA and PBS groups. Immune responses associated with viral clearance were essentially the same, but expression of granulocyte-associated chemokines was higher, M2 macrophage responses were predominant, and the higher spike-specific IgG1/IgG2a ratio in the OVA group post-infection. Infection localized in the alveolar region earlier in the OVA group, resulting in more severe alveolar damage than in the PBS group. These data suggest a Th2-shifted immune background and altered localization of SARS-CoV-2 susceptible cells in mice with OVA-induced airway allergy, which reflect Omicron BA.5 infection dynamics, viral mutations, and immunopathology.

Potential Protective Factors for Allergic Rhinitis Patients Infected with COVID-19

At the beginning of the 2019 coronavirus disease (COVID-19) pandemic, airway allergic diseases such as asthma and allergic rhinitis (AR) were considered as risk factors for COVID-19, as they would aggravate symptoms. With further research, more and more literature has shown that airway allergic disease may not be a high-risk factor, but may be a protective factor for COVID-19 infection, which is closely related to its low-level expression of the ACE2 receptor and the complex cytokines network as underlying molecular regulatory mechanisms. In addition, steroid hormones and age factors could not be ignored. In this review, we have summarized some current evidence on the relationship between COVID-19 and allergic rhinitis to highlight the underlying mechanisms of COVID-19 infection and provide novel insights for its prevention and treatment. The key findings show that allergic rhinitis and its related molecular mechanisms may have a protective effect against COVID-19 infection.

Allergic diseases aggravate the symptoms of SARS-CoV-2 infection in China

Background

The relationship between allergic diseases and the adverse outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been a subject of controversy. This study aimed to investigate the association between allergic diseases and the incidence and severity of symptoms in SARS-CoV-2 infection.

Methods

Clinical data of individuals, including children and their parents, infected with SARS-CoV-2 from December 2022 to January 2023 in China were retrospectively analyzed. The data were collected through questionnaires. Statistical analysis, including chi-squared tests, nonparametric analysis, one-way ANOVA, and logistic regression analysis, was used to examine the relationship between allergic diseases, prior medication, and the symptoms of SARS-CoV-2 infection.

Results

There were 3,517 adults and 3,372 children with SARS-CoV-2 infection included in the study. Fever was found to occur at similar rates in children (86.5%) and adults (86.8%). However, other symptoms related to respiratory issues (such as cough and sore throat), neurological symptoms (headache, loss of smell, and loss of taste), and systemic symptoms (muscle soreness and weakness) were observed more frequently in adults (P < 0.001). Additionally, adults exhibited higher overall symptom scores, indicating greater severity. Allergic diseases were found to be associated with the incidence of certain SARS-CoV-2 infection symptoms in both children and adults. Specifically, children with allergic rhinitis (AR) were observed to be more susceptible to upper respiratory symptoms (OR: 1.320, 95% CI: 1.081-1.611, P = 0.006), while asthma patients were found to be more susceptible to severe respiratory symptoms (OR: 1.736, 95% CI: 1.250-2.411, P = 0.001). Similar patterns were identified in adults. Furthermore, AR was also suggested to be a risk factor for symptom severity in both children (OR: 1.704, 95% CI: 1.314-2.209, P < 0.001) and adults (OR: 1.736, 95% CI: 1.250-2.411, P = 0.001). However, prior medication for allergic diseases did not exhibit a preventive effect on SARS-CoV-2 infection symptoms.

Conclusions

Both children and adults with allergic diseases were found to be more prone to experiencing symptoms of SARS-CoV-2 infection, and these symptoms tended to be more severe.

The relationship between sublingual immunotherapy for allergic rhinitis and the risk of symptoms in patients with COVID-19 infection

To evaluated the risk ratio of Allergic rhinitis (AR) people on the symptoms after COVID-19 infection, and explored the relationship between AR and the symptoms after COVID-19 infection. An observational study was performed of people from outpatient department of the Hospital of Chengdu University of Chinese Medicine. Participants completed an electronic survey and between January 10 to January 20, 2023. We divided the participants into three groups according to the disease information of the population: non-AR people group (AR-N), AR patients with sublingual immunotherapy group (AR-S), and AR patients with conventional therapy group (AR-C). A total of 1116 participants were included in the study, with an average age of 21.76 ± 8.713, women accounted for 62.5%, men accounted for 37.5%. The final results showed that the risk of most symptoms after AR-C infection was not different from that of AR-N, except for sore throat, dry and itchy, chest distress, shortness of breath, and dyspnea. AR-S could effectively reduce the risk of post-infection symptoms including: dry and itchy (OR = 0.484, 95%CI: 0.335-0.698), pain (OR = 0.513, 95%CI:0.362-0.728), cough (OR = 0.506, 95% CI:0.341-0.749), expectoration (OR = 0.349, 95% CI:0.244-0.498), fever (OR = 0.569, 95% CI:0.379-0.853), head and body pain (OR = 0.456, 95% CI:0.323-0.644), fatigue (OR = 0.256, 95% CI:0.177-0.371), cold limbs (OR = 0.325, 95%CI:0.227-0.465), diarrhea (OR = 0.246, 95% CI:0.132-0.457), constipation (OR = 0.227, 95%CI:0.100-0.513), hyposmia (OR = 0.456, 95% CI:0.296-0.701), hypogeusia (OR = 0.397, 95% CI:0.259-0.607), chest distress (OR = 0.534, 95% CI:0.343-0.829), shortness of breath (OR = 0.622, 95% CI:0.398-0.974), palpitations (OR = 0.355, 95% CI:0.206-0.613). The risk of symptoms after COVID-19 infection in allergic rhinitis population receiving sublingual immunotherapy is lower.

Exploring genetic associations between allergic diseases and indicators of COVID-19 using mendelian randomization

We carried out a bidirectional Mendelian randomization (MR) including cases of eczema (N = 218,792), asthma (N = 462,933), and allergic rhinitis (N = 112,583). COVID-19 susceptibility (N = 1,683,768), COVID-19 hospitalization (N = 1,887,658), and COVID-19 severe respiratory symptom (N = 1,388,342) were sampled from GWAS database. The MR analysis was primarily based on inverse variance weighted (IVW), supplemented by several other algorithms. In the bidirectional MR analysis, eczema was negatively associated with COVID-19 susceptibility (odds ratio (OR) _IVW = 0.92; p = 0.031) and COVID-19 hospitalization (OR_IVW = 0.81, p = 0.010); asthma was negatively associated with COVID-19 susceptibility (OR_IVW = 0.65, p = 0.005) and COVID-19 severe respiratory symptom (OR_IVW = 0.20, p = 0.001). No significant association was found between allergic rhinitis and COVID-19 susceptibility (OR_IVW = 0.80, p = 0.174), COVID-19 hospitalization (OR_IVW = 0.71, p = 0.207), or COVID-19 severe respiratory symptom (OR_IVW = 0.56; p = 0.167). The reverse MR analysis showed no potential reverse causal association. Our findings provided new evidence that allergic diseases might be associated with different risks of COVID-19 susceptibility, hospitalization, and severe respiratory symptom.

Reshaping the Management of Allergic Rhinitis in Primary Care: Lessons from the COVID-19 Pandemic

The COVID-19 pandemic presented unique challenges to the delivery of healthcare for patients with allergic rhinitis (AR) following its disruption and impact on the healthcare system with profound implications. Reliance on self-care for AR symptom management was substantial during the pandemic with many patients encouraged to only seek in-person medical care when necessary. The advantage of digital technology becomes apparent when patients and healthcare providers had to change and adapt their method of interaction from the regular physical face-to-face consultation to telehealth and mobile health in the provision of care. Despite the pandemic and the ever-evolving post pandemic situation, optimal management of AR remains paramount for both patients and healthcare professionals. A reshaping of the delivery of care is essential to accomplish this goal. In this paper, we present what we have learned about AR management during the COVID-19 pandemic, the role of digital technology in revolutionizing AR healthcare, screening assessment in the identification and differentiation of common upper respiratory conditions, and a framework to facilitate the management of AR in primary care.

Identification of TCR repertoires in asymptomatic COVID-19 patients by single-cell T-cell receptor sequencing

The T cell-mediated immune responses associated with asymptomatic infection (AS) of SARS-CoV-2 remain largely unknown. The diversity of T-cell receptor (TCR) repertoire is essential for generating effective immunity against viral infections in T cell response. Here, we performed the single-cell TCR sequencing of the PBMC samples from five AS subjects, 33 symptomatic COVID-19 patients and eleven healthy controls to investigate the size and the diversity of TCR repertoire. We subsequently analyzed the TCR repertoire diversity, the V and J gene segment deference, and the dominant combination of αβ VJ gene pairing among these three study groups. Notably, we revealed significant TCR preference in the AS group, including the skewed usage of TRAV1-2-J33-TRBV6-4-J2-2 and TRAV1-2-J33-TRBV6-1-J2-3. Our findings may shed new light on understanding the immunopathogenesis of COVID-19 and help identify optimal TCRs for development of novel therapeutic strategies against SARS-CoV-2 infection.

COVID-19 Phenotypes and Comorbidity: A Data-Driven, Pattern Recognition Approach Using National Representative Data from the United States

The aim of our study was to determine COVID-19 syndromic phenotypes in a data-driven manner using the survey results based on survey results from Carnegie Mellon University’s Delphi Group. Monthly survey results (>1 million responders per month; 320,326 responders with a certain COVID-19 test status and disease duration <30 days were included in this study) were used sequentially in identifying and validating COVID-19 syndromic phenotypes. Logistic Regression-weighted multiple correspondence analysis (LRW-MCA) was used as a preprocessing procedure, in order to weigh and transform symptoms recorded by the survey to eigenspace coordinates, capturing a total variance of >75%. These scores, along with symptom duration, were subsequently used by the Two Step Clustering algorithm to produce symptom clusters. Post-hoc logistic regression models adjusting for age, gender, and comorbidities and confirmatory linear principal components analyses were used to further explore the data. Model creation, based on August’s 66,165 included responders, was subsequently validated in data from March−December 2020. Five validated COVID-19 syndromes were identified in August: 1. Afebrile (0%), Non-Coughing (0%), Oligosymptomatic (ANCOS); 2. Febrile (100%) Multisymptomatic (FMS); 3. Afebrile (0%) Coughing (100%) Oligosymptomatic (ACOS); 4. Oligosymptomatic with additional self-described symptoms (100%; OSDS); 5. Olfaction/Gustatory Impairment Predominant (100%; OGIP). Our findings indicate that the COVID-19 spectrum may be undetectable when applying current disease definitions focusing on respiratory symptoms alone.

Recent Insights into COVID-19 in Children and Clinical Recommendations

Pediatric coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome in children (MIS-C) have been recognized in multiple countries globally. In this review, we provide recent insights into SARS-CoV-2 infection in children from epidemiological, clinical, and laboratory perspectives, including reports on the disease course and therapy. We highlight key features of SARS-CoV-2 infection in children, the relationship between MIS-C and Kawasaki disease, and summarize treatment guidelines for COVID-19 in children from institutional protocols from Colombia, case reports, recommendations based on expert consensus, and official statements from organizations such as the World Health Organization (WHO), United States Center for Disease Control (CDC), Colombian Association of Infectious Diseases, and the Colombian Society of Pediatrics. Finally, we discuss gaps in research with suggestions for future research on the pathogenesis underlying pediatric COVID-19.

Impact of mental health on disease activity in mastocytosis during COVID-19 pandemic

BACKGROUND

Mast cell-related symptoms might be influenced by mental health status in mastocytosis. In this study, we aimed to investigate the influence of mental health problems developed during the COVID-19 pandemic on the course of mastocytosis.

METHODS

Mental health status in 60 adult patients with mastocytosis was prospectively evaluated with the total Depression-Anxiety-Stress Scale (tDASS-21) and Fear of COVID-19 Scale (FCV-19S) in the lockdown period (LP) and the return to normal period (RTNP) during the pandemic. The disease course was assessed from emergency and outpatient medical reports, including Scoring Mastocytosis (SCORMA) index and serum baseline tryptase levels, by telephone interviews and clinical visits.

RESULTS

The mean FCV-19S and median tDASS-21 scores were significantly higher in LP than RTNP (p < 0.001) and there was a positive correlation between FCV-19S and tDASS-21 in LP (r = 0.820, p < 0.001) and in RTNP (r = 0.572 p= <0.001). Disease-related symptoms including skin lesions, flushing and anaphylaxis attacks increased in 22 patients in LP, and in this group, mean FCV-19S and median tDASS-21 were higher than those without symptom exacerbation (p < 0.001). During the study period, four (6.7%) patients who experienced COVID-19 recovered without any requirement for hospitalization and had not experienced symptom exacerbation.

CONCLUSIONS

Fear of COVID-19 can be a reason for mental health changes, including depression, anxiety and stress which may further increase mast cell-related symptoms. Therefore, psychological support is important to control the severity of mast cell-related symptoms in mastocytosis during a pandemic.

COVID-19 with Rapid Progression to Hypoxemia Likely due to Imbalance between Ventilation and Blood Flow: A Case Report

BACKGROUND

In COVID-19 pneumonia, cases of severe hypoxemia in the early stage and cases of sudden deterioration in respiratory status due to silent hypoxia leading to death, have been reported.

CASE SUMMARY

A 70-year-old Japanese man with essential hypertension, dyslipidemia, chronic kidney disease and emphysema was hospitalized with the novel coronavirus disease. He had hypoxemia that was disproportionate to the severity of pneumonia indicated by computed tomography (CT), along with coagulation abnormalities. We speculated that there was a high possibility that he had developed ventilation and blood flow imbalance due to pulmonary intravascular coagulopathy (PIC) or hypoxic pulmonary vasoconstriction (HPV). In this case, early, short-term combination therapy with remdesivir, nafamostat mesylate and low-dose dexamethasone (Dex) was successful.

CONCLUSION

In COVID-19 patients with multiple comorbidities who have hypoxemia and coagulation abnormalities that are disproportionate to the severity of pneumonia on CT, it is important to commence antiviral and anticoagulant therapy as soon as possible, followed by use of a low dose of Dex.

Regulation of the Expression of SARS-CoV-2 Receptor Angiotensin-Converting Enzyme 2 in Nasal Mucosa

BACKGROUND

Coronavirus disease 2019 (COVID-19) has caused a global pandemic. Higher expression of the virus receptor angiotensin-converting enzyme 2 (ACE2) in the nasal mucosa may be associated with high transmissibility and asymptomatic infection. In COVID-19, the elucidation of the determinants of ACE2 expression at nasal tissue level is crucial. The development of strategies to downregulate ACE2 expression in nasal epithelial cells might reduce transmission and be useful as a novel therapeutic approach.

OBJECTIVE

To verify ACE2 expression in the nasal mucosa of patients with seasonal allergic rhinitis induced by Japanese cedar pollen (SAR-JCP) and chronic rhinosinusitis with nasal polyp (CRSwNP) and to examine the effects of short-chain fatty acids (SCFAs) on ACE2 expression in airway epithelial cells.

METHODS

We assessed ACE2 expression in the nasal mucosa of control subjects, patients with SAR-JCP, and those with CRSwNP using real-time polymerase chain reaction. We also quantified ACE2 gene expression in cultured airway epithelial cells.

RESULTS

Although ACE2 expression was greatly increased in a few patients with SAR-JCP during the Japanese cedar pollen season, mean levels were not significantly increased. ACE2 mRNA expression was significantly decreased in nasal polyp tissue from patients with chronic rhinosinusitis compared with the expression in that from control subjects. SCFAs generated by gastrointestinal microbiota significantly reduced resting ACE2 expression in cultured airway epithelial cells. SCFAs also significantly suppressed the dsRNA-dependent upregulation of ACE2 expression in airway epithelial cells.

CONCLUSION

Inflammatory endotype affects ACE2 expression in the nasal mucosa and influences susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In particular, type 2 inflammation could downregulate ACE2 expression in the nasal mucosa and reduces susceptibility to SARS-CoV-2 in patients with CRSwNP. Although in vivo experiments are required, administration of SCFAs to the nasal cavity might be worthy of consideration as a preventative or therapeutic strategy for the early-stage COVID-19.

Advances in clinical outcomes: what we have learned during the COVID-19 pandemic

Our understanding of risk factors and interventions influencing outcomes from coronavirus disease 2019 (COVID-19) has continued to evolve, revealing advances emerging from hypotheses formed at the start of the pandemic. Epidemiologic studies have shown that asthma control, rather than a diagnosis of asthma, is a determinant of COVID-19 severity. Clinical outcomes in patients with primary immunodeficiencies, even in those with impaired cellular immunity, are variable. IL-6 has emerged as a reliable biomarker of COVID-19 severity, and large clinical trials have shown the potential for improving outcomes through inhibition of IL-6 signaling in some patients. Studies of genetic risk factors for severe COVID-19 have also revealed the importance of interferon homeostasis in the defense against severe acute respiratory syndrome coronavirus 2. Because COVID-19 vaccines constitute the primary tool for ending this pandemic, strategies have been developed to address potential allergic and immune-mediated reactions. Here, we discuss advances in our understanding of COVID-19 risk factors and outcomes within the context of allergic and immunologic mechanisms.

Facts and Challenges about Asthma and COVID-19 among the Paediatric Population: A Systematic Literature Review

A systematic review of the literature was conducted to analyse the factors that affect the probability of the paediatric asthma population suffering from COVID-19 or SARS-CoV-2, such as asthma phenotypes, inhaled corticosteroids, and the effects of lockdown. This systematic review was based on PRISMA guidelines. A bibliographic search was conducted using BNE, BVS (LILAC), CSIC (IME, ISOC), IBECS, Scielo, Scopus, Medline, and PubMed, using the following search profile: (COVID-19 or 2019-NCOV or SARS-CoV-2 or COV-19) AND asthma AND (children or adolescents or youths or children or teenagers). The results were limited to those articles published between December 2019 and December 2020, selecting only articles published in Spanish, English and French that included the study population (children aged 0–18 years). Among the 1066 results of the bibliographic search and seven articles selected from a manual search, only 19 articles were found to fit our eligibility criteria. Most of the articles highlight the effects of lockdown on the paediatric asthma population, increased therapeutic compliance, and the role of inhaled corticosteroids and intrinsic factors such as ACE2 receptors as causes of the decreased prevalence of COVID-19 among the paediatric asthma population. This population has unique characteristics that serve as protective factors against COVID-19. The safety measures implemented during the lockdown period along with inhaled corticosteroid treatment also contributed to this protection.

A review on the effect of prolyl isomerization on immune response aberration and hypersensitivity reactions: A unifying hypothesis

Little is known about the causes and mechanisms of ectopic immune responses, including different types of hypersensitivity, superantigens, and cytokine storms. Two of the most questionable phenomena observed in immunology are why the intensity and extent of immune responses to different antigens are different, and why some self-antigens are attacked as foreign. The secondary structure of the peptides involved in the immune system, such as the epitope-paratope interfaces plays a pivotal role in the resulting immune responses. Prolyl cis/trans isomerization plays a fundamental role in the form of the secondary structure and the folding of proteins. This review covers some of the emerging evidence indicating the impact of prolyl isomerization on protein conformation, aberration of immune responses, and the development of hypersensitivity reactions.

Allergic Diseases: A Comprehensive Review on Risk Factors, Immunological Mechanisms, Link with COVID-19, Potential Treatments, and Role of Allergen Bioinformatics

The prevalence of allergic diseases is regarded as one of the key challenges in health worldwide. Although the precise mechanisms underlying this rapid increase in prevalence are unknown, emerging evidence suggests that genetic and environmental factors play a significant role. The immune system, microbiota, viruses, and bacteria have all been linked to the onset of allergy disorders in recent years. Avoiding allergen exposure is the best treatment option; however, steroids, antihistamines, and other symptom-relieving drugs are also used. Allergen bioinformatics encompasses both computational tools/methods and allergen-related data resources for managing, archiving, and analyzing allergological data. This study highlights allergy-promoting mechanisms, algorithms, and concepts in allergen bioinformatics, as well as major areas for future research in the field of allergology.

CRP, SAA, LDH, and DD predict poor prognosis of coronavirus disease (COVID-19): a meta-analysis from 7739 patients

Understanding factors associated with disease severity and mortality from coronavirus disease (COVID-19) was critical for effective risk stratification. We aimed to investigate the association between biomarkers of clinical laboratory tests, including serum C-reactive protein (CRP), serum amyloid protein (SAA), lactate dehydrogenase (LDH), and D-dimer (DD) and poor prognosis of COVID-19. We have searched many studies on COVID-19 on PubMed (Medline), Web of Science and Cochrane until 1 March 2021. The interest of this study was original articles reporting on laboratory testing projects and outcome of patients with COVID-19 that comprises mortality, acute respiratory distress syndrome (ARDS), need for care in an intensive care unit (ICU), and severe COVID-19. After synthesizing all data, we performed meta-analysis of random effects, and determined mean difference (MD) and standard mean difference at the biomarker level for different disease severity. A total of 7,739 patients with COVID-19 were pooled from 32 studies. CRP was significantly associated with poor prognosis of COVID-19 (SMD = 0.98, 95% CI = (0.85, 1.11), p < .001). Elevated SAA was associated with an increased composite poor outcome in COVID-19 (SMD = 1.06, 95% CI = (0.39, 1.72), p = .002). An elevated LDH was associated with a composite poor outcome (SMD = 1.18, 95% CI = (1.00, 1.36), p < .001). Patients with a composite poor outcome had a higher DD level (SMD = 0.91, 95% CI = (0.79, 1.02), p < .001). This meta-analysis showed that elevated serum CRP, SAA, LDH, and DD were associated with a poor outcome in COVID-19.

Association of Asthma and Rhinitis with Epigenetics of Coronavirus Related Genes

Introduction:

Susceptibility factors for coronavirus disease 2019 (COVID-19) include sex and medical conditions such as asthma and rhinitis. DNA methylation (DNAm) is associated with asthma, rhinitis, and several viruses. We examined associations of asthma/rhinitis with DNAm at CpGs located on coronavirus related genes, and if these associations were sex-specific.

Methods:

In total, n = 242 subjects aged 26 years from the Isle of Wight Birth Cohort were included in the study. Linear regressions were used to examine sex specific and non-specific associations of DNAm at CpGs on coronavirus related genes with asthma/rhinitis status. Associations of DNAm with gene expression in blood were assessed for functional relevance of identified CpGs.

Results:

Statistically significant interaction effects of asthma or rhinitis with sex were identified at 40 CpGs for asthma and 27 CpGs for rhinitis. At 21 CpGs, DNAm was associated with asthma, and at 45 CpGs with rhinitis, regardless of sex. Assessment of functional relevance of the identified CpGs indicated a potential of epigenetic regulatory functionality on gene activity at 14 CpGs for asthma and 17 CpGs for rhinitis, and of those 6 CpGs for asthma and 7 CpGs for rhinitis were likely to be sex-specific.

Conclusion:

Subjects with asthma/rhinitis may have altered susceptibility to COVID-19 due to changes in their DNAm associated with these conditions. Sex specificity on association of asthma/rhinitis with DNAm at certain CpGs, and on the association of DNAm at asthma/rhinitis-linked CpGs with gene expression have the potential to explain the reported sex-specificity in COVID-19 morbidity and mortality.

The Young Age and Plant-Based Diet Hypothesis for Low SARS-CoV-2 Infection and COVID-19 Pandemic in Sub-Saharan Africa

Since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that caused the coronavirus disease-19 (COVID-19), in December 2019, the infection has spread around the globe. Some of the risk factors include social distancing, mask wearing, hand washing with soap, obesity, diabetes, hypertension, asthma, cardiovascular disease, and dysbiosis. Evidence has shown the incidence of total infection and death rates to be lower in sub-Saharan Africa when compared with North Africa, Europe and North America and many other parts of the world. The higher the metabolic syndrome rate, the higher the risk of SARS-CoV-2 infection. Africa has a lower rate of metabolic syndrome risk than many other continents. This paradox has puzzled several in the biomedical and scientific communities. Published results of research have demonstrated the exciting correlation that the combination of young age of the population coupled with their native plant-based diet has lowered their risk factors. The plant-based diet include whole grains (millet, sorghum), legumes (black-eye peas, dry beans, soybean), vegetables, potato, sweet potato, yams, squash, banana, pumpkin seeds, and moringa leaves, and lower consumption of meat. The plant-based diet results in a different gut microbiota than of most of the rest of the world. This has a significant impact on the survival rate of other populations. The "plant-based diet" results in lower rates of obesity, diabetes and dysbiosis, which could contribute to lower and less severe infections. However, these hypotheses need to be supported by more clinical and biostatistics data.

Antimicrobial Peptides and Physical Activity: A Great Hope against COVID 19

Antimicrobial peptides (AMPs), α- and β-defensins, possess antiviral properties. These AMPs achieve viral inhibition through different mechanisms of action. For example, they can: (i) bind directly to virions; (ii) bind to and modulate host cell-surface receptors, disrupting intracellular signaling; (iii) function as chemokines to augment and alter adaptive immune responses. Given their antiviral properties and the fact that the development of an effective coronavirus disease 2019 (COVID-19) treatment is an urgent public health priority, they and their derivatives are being explored as potential therapies against COVID-19. These explorations using various strategies, range from their direct interaction with the virus to using them as vaccine adjuvants. However, AMPs do not work in isolation, specifically in their role as potent immune modulators, where they interact with toll-like receptors (TLRs) and chemokine receptors. Both of these receptors have been shown to play roles in COVID-19 pathogenesis. In addition, it is known that a healthy lifestyle accompanied by controlled physical activity can represent a natural weapon against COVID-19. In competitive athletes, an increase in serum defensins has been shown to function as self-protection from the attack of microorganisms, consequently a controlled physical activity could act as a support to any therapies in fighting COVID-19. Therefore, including information on all these players' interactions would produce a complete picture of AMP-based therapies' response.

Seroprevalence of SARS-CoV-2 in Pakistan: an update on epidemiological trends

The emergence of the pandemic in 2020 is a huge threat to global public health. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was first reported in China in December 2019 and later spread to almost all parts of the world in four months and declared as a pandemic in March 2020. SARS-CoV-2 has infected 15.8 million people worldwide while 641,000 died of it. This study aims to report the seroprevalence of SARS-CoV-2 in Pakistan. Of total of 635 samples of symptomatic individuals processed at Genome Center for Molecular Based Diagnostics and Research Pakistan, 313 (49.3%) were found SARS-CoV-2 seropositive. The study also confirmed more seroprevalence in elderly patients (>80 years) and children less than 13 years.

Nutritional status, diet and viral respiratory infections: perspectives for severe acute respiratory syndrome coronavirus 2

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was recognised by the WHO as a pandemic in 2020. Host preparation to combat the virus is an important strategy to avoid COVID-19 severity. Thus, the relationship between eating habits, nutritional status and their effects on the immune response and further implications in viral respiratory infections is an important topic discussed in this review. Malnutrition causes the most diverse alterations in the immune system, suppressing of the immune response and increasing the susceptibility to infections such as SARS-CoV-2. On the other hand, obesity induces low-grade chronic inflammation caused by excess adiposity, which increases angiotensin-converting enzyme 2. It decreases the immune response favouring SARS-CoV-2 virulence and promoting respiratory distress syndrome. The present review highlights the importance of food choices considering their inflammatory effects, consequently increasing the viral susceptibility observed in malnutrition and obesity. Healthy eating habits, micronutrients, bioactive compounds and probiotics are strategies for COVID-19 prevention. Therefore, a diversified and balanced diet can contribute to the improvement of the immune response to viral infections such as COVID-19.

Indomethacin: Can It Counteract Bradykinin Effects in COVID-19 Patients?

COVID-19 represents the biggest health challenge. Although the mortality rate of COVID-19 is low, the high numbers of infected people and those with post-COVID-19 symptoms represent a real problem for the health system. A high number of patients with COVID-19 or people recovered from COVID-19 suffer from a dry cough and/or myalgia. Interestingly, an imbalance in bradykinin was observed in COVID-19 patients, which might be due to the accumulation of bradykinin as a result of a reduction in the degradation of bradykinin. This finding inspired the idea of possible similitude between the dry cough that is induced by angiotensin-converting enzyme inhibitors and the COVID-19-induced dry cough. Both of these types of cough are mediated, at least partially, by bradykinin. They both manifested as a persistent dry cough that is not responded to traditional dry cough remedies. However, several drugs were previously investigated for the treatment of angiotensin-converting enzyme inhibitor–induced dry cough. Here, we hypothesized that such treatment might be useful in COVID-19-induced dry cough and other bradykinin-related symptoms such as generalized pain and myalgia. In this article, evidence was presented to support the use of indomethacin as a potential treatment of COVID-19-induced dry cough. The choice of indomethacin was based on its ability to suppress the cyclooxygenase enzyme while also lowering the level of the inflammatory mediator bradykinin. Furthermore, indomethacin has been shown to be effective in treating angiotensin-converting enzyme inhibitor–induced dry cough. Moreover, indomethacin is a long-established, low-cost, effective, and readily available medication.

Dependence of SARS-CoV-2 infection on cholesterol-rich lipid raft and endosomal acidification

Coronavirus disease 2019 is a kind of viral pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the mechanism whereby SARS-CoV-2 invades host cells remains poorly understood. Here we used SARS-CoV-2 pseudoviruses to infect human angiotensin-converting enzyme 2 (ACE2) expressing HEK293T cells and evaluated virus infection. We confirmed that SARS-CoV-2 entry was dependent on ACE2 and sensitive to pH of endosome/lysosome in HEK293T cells. The infection of SARS-CoV-2 pseudoviruses is independent of dynamin, clathrin, caveolin and endophilin A2, as well as macropinocytosis. Instead, we found that the infection of SARS-CoV-2 pseudoviruses was cholesterol-rich lipid raft dependent. Cholesterol depletion of cell membranes with methyl-β-cyclodextrin resulted in reduction of pseudovirus infection. The infection of SARS-CoV-2 pseudoviruses resumed with cholesterol supplementation. Together, cholesterol-rich lipid rafts, and endosomal acidification, are key steps of SARS-CoV-2 required for infection of host cells. Therefore, our finding expands the understanding of SARS-CoV-2 entry mechanism and provides a new anti-SARS-CoV-2 strategy.

Hypersensitivity reaction to Hyaluronic Acid Dermal filler following novel Coronavirus infection - a case report

The incidence of hypersensitivity reactions to hyaluronic acid dermal fillers is between 0.3 and 4.25%, mediated by T-lymphocytes. Flu-like illness can trigger immunogenic reactions at the site of filler placement. Cases of SARS-CoV-2 are significant and pose a possible risk of inducing hypersensitivity. This case report is of a delayed-type hypersensitivity after hyaluronic acid dermal filler treatment of the nose and subsequent infection with SARS-CoV-2. Risk factors for the development of such symptoms were identified as the presence of hyaluronic acid combined with flu-like illness and repeated treatment of one area. The case resolved without intervention. Clinicians should be mindful of the risk posed by the interaction of hyaluronic acid dermal filler with SARS-CoV-2 in light of the pandemic.

Why Do Some People Develop Serious COVID-19 Disease After Infection, While Others Only Exhibit Mild Symptoms?

The year 2020 was a landmark year of a once-in-a-century pandemic of a novel coronavirus, SARS-CoV-2 virus, that led to a rapidly spreading coronavirus disease (COVID-19). The spectrum of disease with SARS-CoV-2 ranges from asymptomatic to mild upper respiratory illness, to moderate to severe disease with respiratory compromise to acute respiratory distress syndrome, multiorgan failure, and death. Early in the pandemic, risk factors were recognized that contributed to more severe disease, but it became evident that individuals and even young people could have severe COVID-19. As we started to understand the immunobiology of COVID-19, it became clearer that the immune responses to SARS-CoV-2 were variable, and in some cases, the excessive inflammatory response contributed to greater morbidity and mortality. In this review, we will explore some of the additional risk factors that appear to contribute to disease severity and enhance our understanding of why some individuals experience more severe COVID-19. Recent advances in genome-wide associations have identified potential candidate genes in certain populations that may modify the host immune responses leading to dysregulated host immunity. Genetic defects of the type I interferon pathway are also linked to a more clinically severe phenotype of COVID-19. Finally, dysregulation of the adaptive immune system may also play a role in the severity and complex clinical course of patients with COVID-19. A better understanding of the host immune responses to SARS-CoV-2 will hopefully lead to new treatment modalities to prevent the poor outcomes of COVID-19 in those individuals with pre-existing risk factors or genetic variants that contribute to the dysregulated host immune responses.

Platelet and Haemostasis are the Main Targets in Severe Cases of COVID-19 Infection; a System Biology Study

Introduction:

Many proteomics-based and bioinformatics-based efforts are made to detect the molecular mechanism of COVID-19 infection. Identification of the main protein targets and pathways of severe cases of COVID-19 infection is the aim of this study.

Methods:

Published differentially expressed proteins were screened and the significant proteins were investigated via protein-protein interaction network using Cytoscape software V. 3.7.2 and STRING database. The studied proteins were assessed via action map analysis to determine the relationship between individual proteins using CluePedia. The related biological terms were investigated using ClueGO and the terms were clustered and discussed.

Results:

Among the 35 queried proteins, six of them (FGA, FGB, FGG, and FGl1 plus TLN1 and THBS1) were identified as critical proteins. A total of 38 biological terms, clustered in 4 groups, were introduced as the affected terms. “Platelet degranulation” and “hereditary factor I deficiency disease” were introduced as the main class of the terms disturbed by COVID-19 virus.

Conclusion:

It can be concluded that platelet damage and disturbed haemostasis could be the main targets in severe cases of coronavirus infection. It is vital to follow patients’ condition by examining the introduced critical differentially expressed proteins (DEPs).

Viral Infections, the Microbiome, and Probiotics

Viral infections continue to cause considerable morbidity and mortality around the world. Recent rises in these infections are likely due to complex and multifactorial external drivers, including climate change, the increased mobility of people and goods and rapid demographic change to name but a few. In parallel with these external factors, we are gaining a better understanding of the internal factors associated with viral immunity. Increasingly the gastrointestinal (GI) microbiome has been shown to be a significant player in the host immune system, acting as a key regulator of immunity and host defense mechanisms. An increasing body of evidence indicates that disruption of the homeostasis between the GI microbiome and the host immune system can adversely impact viral immunity. This review aims to shed light on our understanding of how host-microbiota interactions shape the immune system, including early life factors, antibiotic exposure, immunosenescence, diet and inflammatory diseases. We also discuss the evidence base for how host commensal organisms and microbiome therapeutics can impact the prevention and/or treatment of viral infections, such as viral gastroenteritis, viral hepatitis, human immunodeficiency virus (HIV), human papilloma virus (HPV), viral upper respiratory tract infections (URTI), influenza and SARS CoV-2. The interplay between the gastrointestinal microbiome, invasive viruses and host physiology is complex and yet to be fully characterized, but increasingly the evidence shows that the microbiome can have an impact on viral disease outcomes. While the current evidence base is informative, further well designed human clinical trials will be needed to fully understand the array of immunological mechanisms underlying this intricate relationship.

Management of Allergic Diseases During COVID-19 Outbreak

PURPOSE OF REVIEW

The coronavirus disease 2019 (COVID-19) has challenged healthcare system capacities and safety for health care workers, reshaping doctor-patient interaction favoring e-Health or telemedicine. The pandemic situation may make difficult to prioritize patients with allergies diseases (AD), face-to-face evaluation, and moreover concern about the possible COVID-19 diagnosis, since COVID-19 shared many symptoms in common with AD. Being COVID-19 a novel disease, everyone is susceptible; there are some advances on vaccine and specific treatment. We evaluate existing literature on allergic diseases (AD): allergic rhinitis, asthma, food allergy, drug allergy, and skin allergy, and potential underlying mechanisms for any interrelationship between AD and COVID-19.

RECENT FINDINGS

There is inconclusive and controversial evidence of the association between AD and the risk of adverse clinical outcomes of COVID-19. AD patients should minimize hospital and face-to-face visits, and those who have used biologics and allergen immunotherapy should continue the treatment. It is essential to wear personal protective equipment for the protection of health care workers. Social distancing, rational use of facemasks, eye protection, and hand disinfection for health care workers and patients deserve further attention and promotion. Teleconsultation during COVID-19 times for AD patients is very encouraging and telemedicine platform can provide a reliable service in patient care.

Clinical and biochemical parameters of COVID-19 patients with prior or active dengue fever

Originated in Wuhan, China, the coronavirus 19 disease (COVID-19) has quickly spread worldwide, reaching countries that already faced other endemics and epidemics. In Brazil, such a concerning situation includes arboviruses, among which the dengue virus stands out. Here, we determined the rate of SARS-CoV-2/dengue virus co-infection in a total of 178 patients with COVID-19 symtoms admitted into a large public hospital of the Federal District of Brazil. Furthermore, we evaluated whether prior or active dengue virus infection influenced hematological, biochemical, and clinical parameters of such patients. One hundred and twelve (63%) individuals tested positive for COVID-19, of which 43 (38.4%) were co-infected with dengue virus, and 50 (44.6%) had antibodies indicative of previous dengue infection. Co-infected patients showed lower numbers of circulating lymphocytes and monocytes, higher glucose rates, and a worse pulmonary condition. Of note, prior infections with dengue virus did not influence clinical parameters, but active dengue fever resulted in higher hospitalization rate. In conclusion, amid the current complex epidemiological scenario in Brazil, our data support the notion that SARS-CoV-2 and dengue co-infection affects an important percentage of COVID-19 patients and leads to worse clinical parameters, requiring greater attention from health authorities.

COVID-19 and Pediatric Asthma: Clinical and Management Challenges

Asthma is the most frequent chronic condition in childhood and a current concern exists about asthma in the pediatric population and its risk for severe SARS-CoV-2 infection. Although all ages can be affected, SARS-CoV-2 infection has lower clinical impact on children and adolescents than on adults. Fever, cough and shortness of breath are the most common symptoms and signs in children; wheezing has not been frequently reported. Published studies suggest that children with asthma do not appear to be disproportionately more affected by COVID-19. This hypothesis raises two issues: is asthma (and/or atopy) an independent protective factor for COVID-19? If yes, why? Explanations for this could include the lower IFN-α production, protective role of eosinophils in the airway, and antiviral and immunomodulatory proprieties of inhaled steroids. Additionally, recent evidence supports that allergic sensitization is inversely related to ACE2 expression. Obesity is a known risk factor for COVID-19 in adults. However, in the childhood asthma-obesity phenotype, the classic atopic Th2 pattern seems to predominate, which could hypothetically be a protective factor for severe SARS-CoV-2 infection in children with both conditions. Finally, the return to school activities raises concerns, as asymptomatic children could act as vectors for the spread of the disease. Although this is still a controversial topic, the identification and management of asymptomatic children is an important approach during the SARS-CoV-2 epidemic. Focus on asthma control, risk stratification, and medication adherence will be essential to allow children with asthma to return safely to school.

Efficacy and safety of acupuncture therapy for asymptomatic infection of COVID-19: A protocol for systematic review and meta-analysis

BACKGROUND

The study aims to evaluate the effectiveness and safety of acupuncture therapy for asymptomatic infection of COVID-19.

METHODS

The following electronic databases will be searched from December 2019 to December 2020: MEDLINE, PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wan-fang database, Chinese Scientific Journal Database (VIP), Chinese Biomedical Literature Databases (CBM), and other databases. All published randomized controlled trials (RCTs) about this topic will be included. Two independent researchers will operate article retrieval, duplication removing, screening, quality evaluation, and data analyses by Review Manager (V.5.3.5). Meta-analyses, subgroup analysis, and/or descriptive analysis will be performed based on the included data conditions.

RESULTS

High-quality synthesis and/or descriptive analysis of current evidence will be provided from the time of negative nucleic acid detection for 2 consecutive times (not on the same day), cure rate, converting to clinical diagnosis rate, and side effects of acupuncture.

CONCLUSION

This study will provide the evidence of whether acupuncture is an effective and safe intervention for asymptomatic infection of COVID-19.

PROSPERO REGISTRATION NUMBER

CRD 42020179729.

Strategies and Advances in Combating COVID-19 in China

Coronavirus disease 2019 (COVID-19)-the third in a series of coronavirus infections-has caused a global public health event in the 21st century, resulting in substantial global morbidity and mortality. Building on its legacy of managing severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), China has played a key role in the scientific community by revealing the viral transmission routes and clinical characteristics of COVID-19 and developing novel therapeutic interventions and vaccines. Despite these rapid scientific and technological advances, uncertainties remain in tracing the original sources of infection, determining the routes of transmission and pathogenesis, and addressing the lack of targeted clinical management of COVID-19. Here, we summarize the major COVID-19 research advances in China in order to provide useful information for global pandemic control.

Efficacy and safety of traditional Chinese medicine combined with routine western medicine for the asymptomatic novel coronavirus disease (COVID-19): A Bayesian network meta-analysis protocol

BACKGROUND

The number of patients infected with novel coronavirus disease (COVID-19) has exceeded 10 million in 2020, and a large proportion of them are asymptomatic. At present, there is still no effective treatment for this disease. Traditional Chinese medicine (TCM) shows a good therapeutic effect on COVID-19, especially for asymptomatic patients. According to the search results, we found that although there are many studies on COVID-19, there are no studies targeting asymptomatic infections. Therefore, we design a network meta-analysis (NMA) to evaluate the therapeutic effect of TCM on asymptomatic COVID-19.

METHODS

We will search Chinese and English databases to collect all randomized controlled trials (RCTs) of TCM combined with conventional western medicine or using only TCM to treat asymptomatic COVID-19 from December 2019 to July 2020. Then, two investigators will independently filter the articles, extract data, and evaluate the risk of bias. We will conduct a Bayesian NMA to evaluate the effects of different therapies. All data will be processed by Stata 16.0 and WinBUGS.

RESULTS

This study will evaluate the effectiveness of various treatments for asymptomatic COVID-19. The outcome indicators include the time when the nucleic acid turned negative, the proportion of patients with disease progression, changes in laboratory indicators, and the side effects of drugs.

CONCLUSION

This analysis will further improve the treatment of asymptomatic COVID-19.

INPLASY REGISTRATION NUMBER

INPLASY202070022.