Community study of role of viral infections in exacerbations of asthma in 9-11 year old children

Patterns of Asthma Medication Use in New Zealand After Publication of National Asthma Guidelines

BACKGROUND

In June 2020, the New Zealand (NZ) adolescent and adult asthma guidelines recommended budesonide/formoterol, taken as maintenance and/or reliever therapy, as the preferred therapeutic approach.

OBJECTIVE

To investigate whether these recommendations were associated with changes in clinical practice indicated by asthma medication use trends.

METHODS

NZ national dispensing data for inhaler medications from January 2010 to December 2021 were reviewed. Monthly "dispensings" of inhaled budesonide/formoterol, inhaled corticosteroid (ICS), other ICS/long-acting β2-agonists (LABA), and inhaled short-acting β2-agonists (SABA), for the 12+ age group, were displayed graphically with piecewise regression used to produce plots of rates by time with a July 1, 2020, break point. The number of dispensings in the last 6 months that data were available (July-December 2021) was compared with the corresponding period, July-December 2019.

RESULTS

Budesonide/formoterol dispensing increased markedly after July 1, 2020 (regression coefficient 41.1 inhalers dispensed/100,000 population per month [95% confidence interval (CI): 36.3-45.6, P < .0001]; 64.7% increase in the number of dispensings between July-December 2019 and July-December 2021), in contrast to "other ICS/LABA" (regression coefficient: -15.9 [95% CI: -22.2 to -9.6, P < .0001]; -1.7% decrease) and SABA (regression coefficient: -14.7 [95% CI: -29.7 to 0.3, P = .055]; -10.6% decrease), respectively.

CONCLUSION

In NZ, a progressive increase in budesonide/formoterol dispensing, accompanied by a reduction in SABA and "other ICS/LABA" dispensing, occurred after publication of the 2020 NZ asthma guidelines. While acknowledging the limitations in the interpretation of temporal associations, these findings suggest that the transition to ICS/formoterol reliever-based therapy can be achieved if recommended and promoted as the preferred therapeutic approach in national guidelines.

Eosinophils as potential biomarkers in respiratory viral infections

Eosinophils are bone marrow-derived granulocytes that, under homeostatic conditions, account for as much as 1-3% of peripheral blood leukocytes. During inflammation, eosinophils can rapidly expand and infiltrate inflamed tissues, guided by cytokines and alarmins (such as IL-33), adhesion molecules and chemokines. Eosinophils play a prominent role in allergic asthma and parasitic infections. Nonetheless, they participate in the immune response against respiratory viruses such as respiratory syncytial virus and influenza. Notably, respiratory viruses are associated with asthma exacerbation. Eosinophils release several molecules endowed with antiviral activity, including cationic proteins, RNases and reactive oxygen and nitrogen species. On the other hand, eosinophils release several cytokines involved in homeostasis maintenance and Th2-related inflammation. In the context of SARS-CoV-2 infection, emerging evidence indicates that eosinophils can represent possible blood-based biomarkers for diagnosis, prognosis, and severity prediction of disease. In particular, eosinopenia seems to be an indicator of severity among patients with COVID-19, whereas an increased eosinophil count is associated with a better prognosis, including a lower incidence of complications and mortality. In the present review, we provide an overview of the role and plasticity of eosinophils focusing on various respiratory viral infections and in the context of viral and allergic disease comorbidities. We will discuss the potential utility of eosinophils as prognostic/predictive immune biomarkers in emerging respiratory viral diseases, particularly COVID-19. Finally, we will revisit some of the relevant methods and tools that have contributed to the advances in the dissection of various eosinophil subsets in different pathological settings for future biomarker definition.

Respiratory issues in patients with multiple sclerosis as a risk factor during SARS-CoV-2 infection: a potential role for exercise

Coronavirus disease-2019 (COVID-19) is associated with cytokine storm and is characterized by acute respiratory distress syndrome (ARDS) and pneumonia problems. The respiratory system is a place of inappropriate activation of the immune system in people with multiple sclerosis (MS), and this may cause damage to the lung and worsen both MS and infections.The concerns for patients with multiple sclerosis are because of an enhance risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The MS patients pose challenges in this pandemic situation, because of the regulatory defect of autoreactivity of the immune system and neurological and respiratory tract symptoms. In this review, we first indicate respiratory issues associated with both diseases. Then, the main mechanisms inducing lung damages and also impairing the respiratory muscles in individuals with both diseases is discussed. At the end, the leading role of physical exercise on mitigating respiratory issues inducing mechanisms is meticulously evaluated.

Breaking Bad: Inflammasome Activation by Respiratory Viruses

The nucleotide-binding domain leucine-rich repeat-containing receptor (NLR) family is a group of intracellular sensors activated in response to harmful stimuli, such as invading pathogens. Some NLR family members form large multiprotein complexes known as inflammasomes, acting as a platform for activating the caspase-1-induced canonical inflammatory pathway. The canonical inflammasome pathway triggers the secretion of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 by the rapid rupture of the plasma cell membrane, subsequently causing an inflammatory cell death program known as pyroptosis, thereby halting viral replication and removing infected cells. Recent studies have highlighted the importance of inflammasome activation in the response against respiratory viral infections, such as influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While inflammasome activity can contribute to the resolution of respiratory virus infections, dysregulated inflammasome activity can also exacerbate immunopathology, leading to tissue damage and hyperinflammation. In this review, we summarize how different respiratory viruses trigger inflammasome pathways and what harmful effects the inflammasome exerts along with its antiviral immune response during viral infection in the lungs. By understanding the crosstalk between invading pathogens and inflammasome regulation, new therapeutic strategies can be exploited to improve the outcomes of respiratory viral infections.

Cough and cough hypersensitivity as treatable traits of asthma

Cough is a common and troublesome symptom in people with asthma and is often associated with poorer asthma control and exacerbations. Apart from asthma, other causes or comorbidities might underlie cough in asthma, such as rhinosinusitis and bronchiectasis. Eosinophilic inflammation and bronchoconstriction can lead to an acute episode of cough or worsen chronic cough. Cough hypersensitivity with laryngeal paraesthesia, allotussia, and hypertussia might underlie the cough of asthma through augmented sensory nerve excitability of upper-airway vagal sensory nerves. Cough associated with bronchoconstriction and type 2 inflammation should respond to inhaled corticosteroids and long-acting β-adrenoceptor agonist therapy. For cough hypersensitivity in adults, speech and language therapy and neuromodulators (eg, gabapentin) could be considered. In children, there is no consistent association of asthma with cough sensitivity or between cough and asthma severity. Further research is needed to realise the potential of cough as a measure of asthma control, to understand the mechanisms of cough in asthma, and to develop safe, effective treatments and a precision-medicine approach to the management of cough in asthma in children and adults.

Update on virus-induced asthma exacerbations

INTRODUCTION

Viral infections are common triggers for asthma exacerbation. Subjects with asthma are more susceptible to viral infections and develop more severe or long-lasting lower respiratory tract symptoms than healthy individuals owing to impaired immune responses. Of the many viruses associated with asthma exacerbation, rhinovirus (RV) is the most frequently identified virus in both adults and children.

AREAS COVERED

We reviewed epidemiological and clinical links and mechanistic studies on virus-associated asthma exacerbations. We included sections on severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), the latest evidence of coronavirus disease 2019 (COVID-19) in asthma patients, and past and future searches for therapeutic and prevention targets.

EXPERT OPINION

Early treatment or prevention of viral infections might significantly reduce the rate of asthma exacerbation, which is one of the key points of disease management. Although it is hypothetically possible nowadays to interfere with every step of the infectious cycle of respiratory tract viruses, vaccination development has provided some of the most encouraging results. Future research should proceed toward the development of a wider spectrum of vaccines to achieve a better quality of life for patients with asthma and to reduce the economic burden on the healthcare system.

Common cold

The common cold is a unique human disease, as it is arguably the most common disease and because of the large number of respiratory viruses causing colds it is one of the most complex of human diseases. This review discusses the respiratory viruses and notes that all these viruses may cause the illness complex recognised as the common cold. The common cold is discussed as part of the "iceberg concept" of disease which ranges from asymptomatic infection to severe illness and death. The factors influencing the incidence of colds are discussed: crowding and sociability, stress, smoking and alcohol, immune status, sex, age, sleep, season, chilling, nutrition and exercise. The mechanism of symptoms related to the innate immune response is explained and symptomatic treatments are tabulated. Morbidity associated with common cold is discussed and possible vaccines.

Macrophages Orchestrate Airway Inflammation, Remodeling, and Resolution in Asthma

Asthma is a heterogenous chronic inflammatory lung disease with endotypes that manifest different immune system profiles, severity, and responses to current therapies. Regardless of endotype, asthma features increased immune cell infiltration, inflammatory cytokine release, and airway remodeling. Lung macrophages are also heterogenous in that there are separate subsets and, depending on the environment, different effector functions. Lung macrophages are important in recruitment of immune cells such as eosinophils, neutrophils, and monocytes that enhance allergic inflammation and initiate T helper cell responses. Persistent lung remodeling including mucus hypersecretion, increased airway smooth muscle mass, and airway fibrosis contributes to progressive lung function decline that is insensitive to current asthma treatments. Macrophages secrete inflammatory mediators that induce airway inflammation and remodeling. Additionally, lung macrophages are instrumental in protecting against pathogens and play a critical role in resolution of inflammation and return to homeostasis. This review summarizes current literature detailing the roles and existing knowledge gaps for macrophages as key inflammatory orchestrators in asthma pathogenesis. We also raise the idea that modulating inflammatory responses in lung macrophages is important for alleviating asthma.

The Notorious Triumvirate in Pediatric Health: Air Pollution, Respiratory Allergy, and Infection

A plausible association is suspected among air pollution, respiratory allergic disorder, and infection. These three factors could cause uncontrollable chronic inflammation in the airway tract, creating a negative impact on the physiology of the respiratory system. This review aims to understand the underlying pathophysiology in explaining the association among air pollution, respiratory allergy, and infection in the pediatric population and to capture the public's attention regarding the interaction among these three factors, as they synergistically reduce the health status of children living in polluted countries globally, including Indonesia.

Roles and Mechanisms of NLRP3 in Influenza Viral Infection

Pathogenic viral infection represents a major challenge to human health. Due to the vast mucosal surface of respiratory tract exposed to the environment, host defense against influenza viruses has perpetually been a considerable challenge. Inflammasomes serve as vital components of the host innate immune system and play a crucial role in responding to viral infections. To cope with influenza viral infection, the host employs inflammasomes and symbiotic microbiota to confer effective protection at the mucosal surface in the lungs. This review article aims to summarize the current findings on the function of NACHT, LRR and PYD domains-containing protein 3 (NLRP3) in host response to influenza viral infection involving various mechanisms including the gut-lung crosstalk.

Knowledge, Attitudes, and Practices of Influenza Vaccination among Parents of Children with Asthma: A Cross-Sectional Study

Asthma is the most common chronic disease in childhood. Exacerbation is a significant problem for asthmatic patients, and viral infections remain the most frequent triggers of asthma exacerbations. This study explored knowledge, attitudes, and practices (KAP) of parents of asthmatic children towards providing influenza vaccine to their children. This cross-sectional study enrolled parents of asthmatic children who visited the outpatient respiratory clinics of two Jordanian hospitals. The present study enrolled 667 parents of asthmatic children (62.8% female). The median age of the participants' children was 7 years. The results showed that 60.4% of the children with asthma never received a flu vaccine. Most of those who had received the flu vaccine reported that the side effects were mild (62.7%). Asthma duration was positively and significantly associated with increased vaccine hesitancy/rejection (OR = 1.093, 95% CI = (1.004-1.190), p = 0.04; and OR = 1.092, 95% CI = (1.002-1.189), p = 0.044, respectively). As the attitude towards flu vaccine score increases, odds of vaccination hesitancy/rejection decreased (OR = 0.735, 95% CI = (0.676-0.800), p < 0.001; and OR = 0.571, 95% CI = (0.514-0.634), p < 0.001, respectively). The main reasons for vaccination hesitancy/refusal included "I don't think my child needs it" (22.3%) followed by "I forget it" (19.5%). The rate of vaccination among children was low and emphasized the necessity of encouraging parents with asthmatic children to vaccinate their children by conducting health awareness campaigns and also emphasized the role of doctors and other healthcare professionals.

Progress in the development of kinase inhibitors for treating asthma and COPD

Current therapies to mitigate inflammatory responses involved in airway remodeling and associated pathological features of asthma and chronic obstructive pulmonary disease (COPD) are limited and largely ineffective. Inflammation and the release of cytokines and growth factors activate kinase signaling pathways that mediate changes in airway mesenchymal cells such as airway smooth muscle cells and lung fibroblasts. Proliferative and secretory changes in mesenchymal cells exacerbate the inflammatory response and promote airway remodeling, which is often characterized by increased airway smooth muscle mass, airway hyperreactivity, increased mucus secretion, and lung fibrosis. Thus, inhibition of relevant kinases has been viewed as a potential therapeutic approach to mitigate the debilitating and, thus far, irreversible airway remodeling that occurs in asthma and COPD. Despite FDA approval of several kinase inhibitors for the treatment of proliferative disorders, such as cancer and inflammation associated with rheumatoid arthritis and ulcerative colitis, none of these drugs have been approved to treat asthma or COPD. This review will provide a brief overview of the role kinases play in the pathology of asthma and COPD and an update on the status of kinase inhibitors currently in clinical trials for the treatment of obstructive pulmonary disease. In addition, potential issues associated with the current kinase inhibitors, which have limited their success as therapeutic agents in treating asthma or COPD, and alternative approaches to target kinase functions will be discussed.

Antibiotic use among admitted pediatric patients in the United States with status asthmaticus before and during the COVID-19 pandemic

OBJECTIVE

Hospital admission trends of children with status asthmaticus diminished during the Coronavirus-19 (COVID-19) pandemic of 2020, possibly secondary to several factors such as school closures and use of face masks. What effect this had on antibiotic prescribing practices has yet to be described. The objective of our study was to evaluate the use of antibiotics in hospitalized children with a diagnosis of status asthmaticus before and during the COVID pandemic.Methods: A retrospective cross-sectional analysis was conducted using the TriNetX® cloud-based program with a national and institutional database. Each database was queried for all inpatient pediatric encounters from 3 to 18 years old, admitted with a diagnosis of status asthmaticus in the spring seasons of 2017-2019. Admission data and antibiotic usage were queried during the COVID-19 pandemic year of 2020 from both databases and compared amongst all study years.Results: In 2020, there was an overall decrease in the number of admissions as compared to the average number from 2017-2019, by 76.9% in the national database (p < 0.05) and 91.2% in the institutional database. The rates of antibiotic prescriptions significantly dropped among the national database (p < 0.001, z = 3.39) and remained non-significantly changed among the institutional database (p = 0.944 and z = 0.073).Conclusions: Our study demonstrates that the COVID-19 pandemic year of 2020 coincided with a significant decrease in hospital admissions and antibiotic prescribing prevalence among children with status asthmaticus on a national level. Nonetheless, our reported trends in antibiotic prescribing are still grossly similar to that of pre-pandemic times and may demonstrate a continued need for antimicrobial stewardship.

Anti-inflammatory effects of medications used for viral infection-induced respiratory diseases

Respiratory viruses like rhinovirus, influenza virus, respiratory syncytial virus, and coronavirus cause several respiratory diseases, such as bronchitis, pneumonia, pulmonary fibrosis, and coronavirus disease 2019, and exacerbate bronchial asthma, chronic obstructive pulmonary disease, bronchiectasis, and diffuse panbronchiolitis. The production of inflammatory mediators and mucin and the accumulation of inflammatory cells have been reported in patients with viral infection-induced respiratory diseases. Interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, granulocyte-macrophage colony-stimulating factor, and regulated on activation normal T-cell expressed and secreted are produced in the cells, including human airway and alveolar epithelial cells, partly through the activation of toll-like receptors, nuclear factor kappa B and p44/42 mitogen-activated protein kinase. These mediators are associated with the development of viral infection-induced respiratory diseases through the induction of inflammation and injury in the airway and lung, airway remodeling and hyperresponsiveness, and mucus secretion. Medications used to treat respiratory diseases, including corticosteroids, long-acting β2-agonists, long-acting muscarinic antagonists, mucolytic agents, antiviral drugs for severe acute respiratory syndrome coronavirus 2 and influenza virus, macrolides, and Kampo medicines, reduce the production of viral infection-induced mediators, including cytokines and mucin, as determined in clinical, in vivo, or in vitro studies. These results suggest that the anti-inflammatory effects of these medications on viral infection-induced respiratory diseases may be associated with clinical benefits, such as improvements in symptoms, quality of life, and mortality rate, and can prevent hospitalization and the exacerbation of chronic obstructive pulmonary disease, bronchial asthma, bronchiectasis, and diffuse panbronchiolitis.

Lung-on-chip microdevices to foster pulmonary drug discovery

Respiratory diseases account for unprecedented mortality owing to a lack of personalized or insufficient therapeutic interventions. Fostering pulmonary research into managing pulmonary threat requires a potential alternative approach that can mimick the in vivo complexities of the human body. The in vitro miniaturized bionic simulation of the lung holds great potential in the quest for a successful therapeutic intervention. This review discusses the emerging roles of lung-on-chip microfluidic simulator devices in fostering translational pulmonary drug discovery and personalized medicine. This review also explicates how the lung-on-chip model emulates the breathing patterns, elasticity, and vascularization of lungs in creating a 3D pulmonary microenvironment.

Risk Factors of Severe COVID-19: A Review of Host, Viral and Environmental Factors

The clinical course and outcome of COVID-19 are highly variable, ranging from asymptomatic infections to severe disease and death. Understanding the risk factors of severe COVID-19 is relevant both in the clinical setting and at the epidemiological level. Here, we provide an overview of host, viral and environmental factors that have been shown or (in some cases) hypothesized to be associated with severe clinical outcomes. The factors considered in detail include the age and frailty, genetic polymorphisms, biological sex (and pregnancy), co- and superinfections, non-communicable comorbidities, immunological history, microbiota, and lifestyle of the patient; viral genetic variation and infecting dose; socioeconomic factors; and air pollution. For each category, we compile (sometimes conflicting) evidence for the association of the factor with COVID-19 outcomes (including the strength of the effect) and outline possible action mechanisms. We also discuss the complex interactions between the various risk factors.

Asthma Care in the Elderly: Practical Guidance and Challenges for Clinical Management - A Framework of 5 "Ps"

Uncontrolled asthma in the elderly is a public health issue recognized in developed countries such as the United States and among the European Union, both from patient safety and economic perspectives. Variations in the cutoff, which defines elderly age, contribute to epidemiological study difficulties. Nonetheless, the relevance of elderly asthma from a socioeconomic perspective is inarguable. The projected growth of the enlarging geriatric population in the United States portends an impending national health burden that may or may not be preventable with pharmacologic and non-pharmacologic treatments. Asthma in the elderly might be a consequence of uncontrolled disease that is carried throughout a lifetime. Or elderly asthmatics could suffer from uncontrolled asthma, which overlaps with other ailments common with advancing ages that merit consideration, eg, COPD, heart disease, OSA, diabetes mellitus, and other comorbidities. Because of the heterogeneity of asthma phenotypes and other conditions that could mimic the symptoms of elderly asthma, further cohort studies are needed to elucidate the elderly asthmatic pathophysiology and management. More studies to characterize elderly asthma can help address these patients' unmet need for evidence-based guidelines. We introduce the 5 "Ps" (phenotypes, partnership, pharmacology, practice in acute exacerbations, and problems or barriers for the elderly asthmatics) that establish a framework approach for clinical practice.

Associations between outdoor air pollutants and non-viral asthma exacerbations and airway inflammatory responses in children and adolescents living in urban areas in the USA: a retrospective secondary analysis

BACKGROUND

Asthma prevalence and severity have markedly increased with urbanisation, and children in low-income urban centres have among the greatest asthma morbidity. Outdoor air pollution has been associated with adverse respiratory effects in children with asthma. However, the mechanisms by which air pollution exposure exacerbates asthma, and how these mechanisms compare with exacerbations induced by respiratory viruses, are poorly understood. We aimed to investigate the associations between regional air pollutant concentrations, respiratory illnesses, lung function, and upper airway transcriptional signatures in children with asthma, with particular focus on asthma exacerbations occurring in the absence of respiratory virus.

METHODS

We performed a retrospective analysis of data from the MUPPITS1 cohort and validated our findings in the ICATA cohort. The MUPPITS1 cohort recruited 208 children aged 6-17 years living in urban areas across nine US cities with exacerbation-prone asthma between Oct 7, 2015, and Oct 18, 2016, and monitored them during reported respiratory illnesses. The last MUPPITS1 study visit occurred on Jan 6, 2017. The ICATA cohort recruited 419 participants aged 6-20 years with persistent allergic asthma living in urban sites across eight US cities between Oct 23, 2006, and March 25, 2008, and the last study visit occurred on Dec 30, 2009. We included participants from the MUPPITS1 cohort who reported a respiratory illness at some point during the follow-up and participants from the ICATA cohort who had nasal samples collected during respiratory illness or at a scheduled visit. We used air quality index values and air pollutant concentrations for PM2·5, PM10, O3, NO2, SO2, CO, and Pb from the US Environmental Protection Agency spanning the years of both cohorts, and matched values and concentrations to each illness for each participant. We investigated the associations between regional air pollutant concentrations and respiratory illnesses and asthma exacerbations, pulmonary function, and upper airway transcriptional signatures by use of a combination of generalised additive models, case crossover analyses, and generalised linear mixed-effects models.

FINDINGS

Of the 208 participants from the MUPPITS1 cohort and 419 participants from the ICATA cohort, 168 participants in the MUPPITS1 cohort (98 male participants and 70 female participants) and 189 participants in the ICATA cohort (115 male participants and 74 female participants) were included in our analysis. We identified that increased air quality index values, driven predominantly by increased PM2·5 and O3 concentrations, were significantly associated with asthma exacerbations and decreases in pulmonary function that occurred in the absence of a provoking viral infection. Moreover, individual pollutants were significantly associated with altered gene expression in coordinated inflammatory pathways, including PM2·5 with increased epithelial induction of tissue kallikreins, mucus hypersecretion, and barrier functions and O3 with increased type-2 inflammation.

INTERPRETATION

Our findings suggest that air pollution is an important independent risk factor for asthma exacerbations in children living in urban areas and is potentially linked to exacerbations through specific inflammatory pathways in the airway. Further investigation of these potential mechanistic pathways could inform asthma prevention and management approaches.

FUNDING

National Institutes of Health, National Institute of Allergy and Infectious Diseases.

A Review Regarding the Connections between Allergic Rhinitis and Asthma - Epidemiology, Diagnosis and Treatment

Allergic rhinitis is characterized by an acute or chronic inflammation of the nasal mucosa, being frequently associated with other airway conditions such as sinusitis, serous otitis media, nasal polyposis, sleep disorders and asthma in particular. Among the comorbidities of allergic rhinitis it counts asthma, being a risk factor for this disorder, in which, more than 75% of patients develop asthma (either allergic or nonallergic), whereas the patients with allergic rhinitis can be affected up to 40% by asthma. The classic symptoms for allergic rhinitis involves sneezing, nasal mucosal swelling and watery rhinorrhea; whereas the main symptoms which occurred in patients with asthma are wheezing, breathlessness, chest tightness, coughing, fast heartbeat, confusion, exhaustion or dizziness. Avoiding allergens is the first line of treatment for allergic rhinitis, followed by medication and allergen immunotherapy. Due to the strong connection between allergic rhinitis and asthma, one can affirm that the treatment for allergic rhinitis lead to the improvement of asthma symptoms. One can diagnose asthma by recognizing a certain pattern of respiratory symptoms and expiratory airflow restriction, which varies for each patient. In conclusion, accurate identification of the differences between allergic rhinitis and asthma depends on a thorough history, physical examination, and therapeutic treatments. This article provides an overview of the connection between these disorders, as well as of the diagnosis of these conditions and their current management options.

Role of Sulfur Compounds in Garlic as Potential Therapeutic Option for Inflammation and Oxidative Stress in Asthma

Asthma is a chronic inflammatory disease in the airways with a multifactorial origin but with inflammation and oxidative stress as related pathogenic mechanisms. Garlic (Allium sativum) is a nutraceutical with different biological properties due to sulfur-containing natural compounds. Studies have shown that several compounds in garlic may have beneficial effects on cardiovascular diseases, including those related to the lungs. Therefore, it is possible to take advantage of the compounds from garlic as nutraceuticals for treating lung diseases. The objective of this article is to review the biological properties of the sulfur compounds present in garlic for the treatment of asthma, as well as the cellular mechanisms involved. Here, we discuss the potential therapeutic effects of garlic compounds in the modulation of inflammation and oxidative stress, as well as its antibiotic and antiviral activities for identifying and testing potential treatment options for asthma management.

Asthma exacerbations: the Achilles heel of asthma care

Asthma exacerbations significantly impact millions of patients worldwide to pose large disease burdens on affected patients, families, and health-care systems. Although numerous environmental factors cause asthma exacerbations, viral respiratory infections are the principal triggers. Advances in the pathophysiology of asthma have elucidated dysregulated protective immune responses and upregulated inflammation that create susceptibility and risks for exacerbation. Biologics for the treatment of severe asthma reduce rates of exacerbations and identify specific pathways of inflammation that contribute to altered pathophysiology, novel therapeutic targets, and informative biomarkers. Major steps to prevent exacerbations include the identification of molecular pathways whose blockage will prevent asthma attacks safely, predictably, and effectively.

Pulse oximetry respiratory monitoring for assessment of acute childhood wheeze

OBJECTIVE

There is a lack of objective measures to assess children with acute wheezing episodes. Increased respiratory rate (RR) and pulsus paradoxus (PP) are recognised markers, but poorly recorded in practice. We examined whether they can be reliably assessed from a pulse oximeter plethysmogram ('pleth') trace and predict clinical outcome.

PATIENTS AND METHODS

We studied 44 children aged 1-7 years attending hospital with acute wheeze, following initial 'burst' bronchodilator therapy (BT), and used custom software to measure RR and assess PP from oximeter pleth traces. Traces were examined for quality, and the accuracy of the RR measurement was validated against simultaneous respiratory inductive plethysmography (RIP). RR and PP at 1 hour after BT were compared with clinical outcomes.

RESULTS

RR from pleth and RIP showed excellent agreement, with a mean difference (RIP minus pleth) of -0.5 breaths per minute (limits of agreement -3.4 to +2.3). 52% of 1 min epochs contained 10 s or more of pleth artefact. At 1 hour after BT, children who subsequently required intravenous bronchodilators had significantly higher RR (median (IQR) 63 (62-66) vs 43 (37-51) breaths per minute) than those who did not, but their heart rate and oxygen saturation were similar. Children with RR ≥55 per minute spent longer in hospital: median (IQR) 30 (22-45) vs 10 (7-21) hours. All children who subsequently required hospital admission had PP-analogous pleth waveforms 1 hour after BT.

CONCLUSION

RR can be reliably measured and PP detected from the pulse oximeter pleth trace in children with acute wheeze and both markers predict clinical outcome.

TRIAL REGISTRATION NUMBER

UKCRN15742.

An Overview on the Primary Factors That Contribute to Non-Allergic Asthma in Children

The prevalence of non-allergic asthma in childhood is low, peaking in late adulthood. It is triggered by factors other than allergens, like cold and dry air, respiratory infections, hormonal changes, smoke and air pollution. In the literature, there are few studies that describe non-allergic asthma in pediatric age. Even though it is a less common disorder in kids, it is crucial to identify the causes in order to keep asthma under control, particularly in patients not responding to conventional treatments. In this review, we discuss non-IgE-mediated forms of asthma, collecting the latest research on etiopathogenesis and treatment.

IL-33 Induces an Antiviral Signature in Mast Cells but Enhances Their Permissiveness for Human Rhinovirus Infection

Mast cells (MCs) are classically associated with allergic asthma but their role in antiviral immunity is unclear. Human rhinoviruses (HRVs) are a major cause of asthma exacerbations and can infect and replicate within MCs. The primary site of HRV infection is the airway epithelium and MCs localise to this site with increasing asthma severity. The asthma susceptibility gene, IL-33, encodes an epithelial-derived cytokine released following HRV infection but its impact on MC antiviral responses has yet to be determined. In this study we investigated the global response of LAD2 MCs to IL-33 stimulation using RNA sequencing and identified genes involved in antiviral immunity. In spite of this, IL-33 treatment increased permissiveness of MCs to HRV16 infection which, from the RNA-Seq data, we attributed to upregulation of ICAM1. Flow cytometric analysis confirmed an IL-33-dependent increase in ICAM1 surface expression as well as LDLR, the receptors used by major and minor group HRVs for cellular entry. Neutralisation of ICAM1 reduced the IL-33-dependent enhancement in HRV16 replication and release in both LAD2 MCs and cord blood derived MCs. These findings demonstrate that although IL-33 induces an antiviral signature in MCs, it also upregulates the receptors for HRV entry to enhance infection. This highlights the potential for a gene-environment interaction involving IL33 and HRV in MCs to contribute to virus-induced asthma exacerbations.

Effects of COVID-19 and Social Distancing on Rhinovirus Infections and Asthma Exacerbations

Since their discovery in the 1950s, rhinoviruses (RVs) have been recognized as a major causative agent of the "common cold" and cold-like illnesses, accounting for more than 50% of upper respiratory tract infections. However, more than that, respiratory viral infections are responsible for approximately 50% of asthma exacerbations in adults and 80% in children. In addition to causing exacerbations of asthma, COPD and other chronic lung diseases, RVs have also been implicated in the pathogenesis of lower respiratory tract infections including bronchiolitis and community acquired pneumonia. Finally, early life respiratory viral infections with RV have been associated with asthma development in children. Due to the vast genetic diversity of RVs (approximately 160 known serotypes), recurrent infection is common. RV infections are generally acquired in the community with transmission occurring via inhalation of aerosols, respiratory droplets or fomites. Following the outbreak of coronavirus disease 2019 (COVID-19), exposure to RV and other respiratory viruses was significantly reduced due to social-distancing, restrictions on social gatherings, and increased hygiene protocols. In the present review, we summarize the impact of COVID-19 preventative measures on the incidence of RV infection and its sequelae.

Construction of a Vero Cell Line Expressing Human ICAM1 for the Development of Rhinovirus Vaccines

Human rhinoviruses (HRVs) are small non-enveloped RNA viruses that belong to the Enterovirus genus within the Picornaviridae family and are known for causing the common cold. Though symptoms are generally mild in healthy individuals, the economic burden associated with HRV infection is significant. A vaccine could prevent disease. The Vero-cell-based viral vaccine platform technology was considered for such vaccine development. Unfortunately, most HRV strains are unable to propagate on Vero cells due to a lack of the major receptor of HRV group A and B, intercellular adhesion molecule (ICAM1, also known as CD54). Therefore, stable human ICAM1 expressing Vero cell clones were generated by transfecting the ICAM1 gene in Vero cells and selecting clones that overexpressed ICAM1 on the cell surface. Cell banks were made and expression of ICAM1 was stable for at least 30 passages. The Vero_ICAM1 cells and parental Vero cells were infected with four HRV prototypes, B14, A16, B37 and A57. Replication of all four viruses was detected in Vero_ICAM1, but not in the parental Vero cells. Altogether, Vero cells expressing ICAM1 could efficiently propagate the tested HRV strains. Therefore, ICAM1-expressing cells could be a useful tool for the development and future production of polyvalent HRV vaccines or other viruses that use ICAM1 as a receptor.

Non-typeable Haemophilus influenzae airways infection: the next treatable trait in asthma?

Asthma is a complex, heterogeneous condition that affects over 350 million people globally. It is characterised by bronchial hyperreactivity and airways inflammation. A subset display marked airway neutrophilia, associated with worse lung function, higher morbidity and poor response to treatment. In these individuals, recent metagenomic studies have identified persistent bacterial infection, particularly with non-encapsulated strains of the Gram-negative bacterium Haemophilus influenzae. Here we review knowledge of non-typeable H. influenzae (NTHi) in the microbiology of asthma, the immune consequences of mucosal NTHi infection, various immune evasion mechanisms, and the clinical implications of NTHi infection for phenotyping and targeted therapies in neutrophilic asthma. Airway neutrophilia is associated with production of neutrophil chemokines and proinflammatory cytokines in the airways, including interleukin (IL)-1β, IL-6, IL-8, IL-12, IL-17A and tumour necrosis factor. NTHi adheres to and invades the lower respiratory tract epithelium, inducing the NLR family pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasomes. NTHi reduces expression of tight-junction proteins, impairing epithelial integrity, and can persist intracellularly. NTHi interacts with rhinoviruses synergistically via upregulation of intracellular cell adhesion molecule 1 and promotion of a neutrophilic environment, to which NTHi is adapted. We highlight the clinical relevance of this emerging pathogen and its relevance for the efficacy of long-term macrolide therapy in airways diseases, we identify important unanswered questions and we propose future directions for research.

Vulnerability for Respiratory Infections in Asthma Patients: A Systematic Review

Asthma is a non-communicable and long-term condition affecting children and adults. The air passages in the lungs become narrow due to inflammation and tightening of the muscles around the small airways. Symptoms of asthma are intermittent and include cough, wheeze, shortness of breath, and chest tightness. Asthma is very often underdiagnosed and under-treated in many regions, especially in developing countries. While many studies show that viral infections can precipitate asthmatic attacks, very few studies have been conducted to see if history or current asthmatic attack increases the risk of viral infections. Our study aims to determine the predisposition of asthmatics to develop various viral infections and susceptibility toward certain viruses that cause upper respiratory tract infections.

We performed a literature review of both published and unpublished articles. We included case reports, case series, reviews, clinical trials, cohort, and case-control studies, written only in English. Commentaries, letters to editors, and book chapters were excluded. Our initial search yielded 948 articles, of which 826 were rejected either because they were irrelevant or because they did not meet our inclusion criteria. We finally screened 122 abstracts and identified 24 relevant articles.

People with a history of asthma have an abnormal innate immune response, making them potentially slower in clearing the infection and susceptible to both infections and virus-induced cell cytotoxicity. Also, in these studies, deficiencies in the interferon alpha response of peripheral blood mononuclear cells and plasmacytoid dendritic cells have been observed in asthmatics, both adults and children. Asthmatics with a viral infection usually present with an acute exacerbation of asthma, represented by dyspnea and cough, with other prodromal symptoms including vomiting and general malaise.

The review includes an update on the relevance of dysregulated immune pathways in causing viral infections in asthmatic populations. It focuses on the evidence to suggest that people with asthma are at increased risk of viral infection, and viral infections in turn are known to precipitate and worsen the asthmatic status, making this a vicious cycle. The authors also suggest that further studies be undertaken to elucidate the pathophysiology and identify the critical therapeutic steps to break this vicious cycle and improve the quality of life for people with asthma.

Exposing the Two Contrasting Faces of STAT2 in Inflammation

Inflammation is a natural immune defense mechanism of the body's response to injury, infection, and other damaging triggers. Uncontrolled inflammation may become chronic and contribute to a range of chronic inflammatory diseases. Signal transducer and activator of transcription 2 (STAT2) is an essential transcription factor exclusive to type I and type III interferon (IFN) signaling pathways. Both pathways are involved in multiple biological processes, including powering the immune system as a means of controlling infection that must be tightly regulated to offset the development of persistent inflammation. While studies depict STAT2 as protective in promoting host defense, new evidence is accumulating that exposes the deleterious side of STAT2 when inappropriately regulated, thus prompting its reevaluation as a signaling molecule with detrimental effects in human disease. This review aims to provide a comprehensive summary of the findings based on literature regarding the inflammatory behavior of STAT2 in microbial infections, cancer, autoimmune, and inflammatory diseases. In conveying the extent of our knowledge of STAT2 as a proinflammatory mediator, the aim of this review is to stimulate further investigations into the role of STAT2 in diseases characterized by deregulated inflammation and the mechanisms responsible for triggering severe responses.

Epithelial cell responses to rhinovirus identify an early-life-onset asthma phenotype in adults

BACKGROUND

The study of pathogenic mechanisms in adult asthma is often marred by a lack of precise information about the natural history of the disease. Children who have persistent wheezing (PW) during the first 6 years of life and whose symptoms start before age 3 years (PW+) are much more likely to have wheezing illnesses due to rhinovirus (RV) in infancy and to have asthma into adult life than are those who do not have PW (PW-).

OBJECTIVE

Our aim was to determine whether nasal epithelial cells from PW+ asthmatic adults as compared with cells from PW- asthmatic adults show distinct biomechanistic processes activated by RV exposure.

METHODS

Air-liquid interface cultures derived from nasal epithelial cells of 36-year old participants with active asthma with and without a history of PW in childhood (10 PW+ participants and 20 PW- participants) from the Tucson Children's Respiratory Study were challenged with a human RV-A strain (RV-A16) or control, and their RNA was sequenced.

RESULTS

A total of 35 differentially expressed genes involved in extracellular remodeling and angiogenesis distinguished the PW+ group from the PW- group at baseline and after RV-A stimulation. Notably, 22 transcriptomic pathways showed PW-by-RV interactions; the pathways were invariably overactivated in PW+ patients, and were involved in Toll-like receptor- and cytokine-mediated responses, remodeling, and angiogenic processes.

CONCLUSIONS

Asthmatic adults with a history of persistent wheeze in the first 6 years of life have specific biomolecular alterations in response to RV-A that are not present in patients without such a history. Targeting these mechanisms may slow the progression of asthma in these patients.

Microarray-Based Analyses of Rhinovirus Species-Specific Antibody Responses in Exacerbated Pediatric Asthma in a German Pediatric Cohort

Rhinoviruses (RV) account for a significant number of asthma exacerbations, and RV species C may be associated with a severe course in vulnerable patient groups. Despite important evidence on the role of RV reported by clinicians and life scientists, there are still unanswered questions regarding their influence on asthma exacerbation in young patients. Thus, we measured the RVspecies-specific IgG titers in our German pediatric exacerbation cohort using a microarray-based technology. For this approach, human sera of patients with exacerbated asthma and wheeze, as well as healthy control subjects (n = 136) were included, and correlation analyses were performed. Concordantly with previously published results, we observed significantly higher cumulative levels of RV species A-specific IgG (p = 0.011) and RV-C-specific IgG (p = 0.051) in exacerbated asthma group compared to age-matched controls. Moreover, atopic wheezers had increased RV-specific IgG levels for species A (p = 0.0011) and species C (p = 0.0009) compared to non-atopic wheezers. Hypothesizing that bacterial infection positively correlates with immune memory against RV, we included nasopharyngeal swab results in our analyses and detected limited correlations. Interestingly, the eosinophil blood titer positively correlated with RV-specific IgG levels. With these observations, we add important observations to the existing data regarding exacerbation in pediatric and adolescent medicine. We propose that scientists and clinicians should pay more attention to the relevance of RV species in susceptible pediatric patients.

A systems immunology approach to investigate cytokine responses to viruses and bacteria and their association with disease

Patterns of human immune responses to viruses and bacteria and how this impacts risk of infections or onset/exacerbation of chronic respiratory diseases are poorly understood. In a population-based birth cohort, we measured peripheral blood mononuclear cell responses (28 cytokines) to respiratory viruses and bacteria, Toll-like receptor ligands and phytohemagglutinin, in 307 children. Cytokine responses were highly variable with > 1000-fold differences between children. Machine learning revealed clear distinction between virus-associated and bacteria-associated stimuli. Cytokines clustered into three functional groups (anti-viral, pro-inflammatory and T-cell derived). To investigate mechanisms potentially explaining such variable responses, we investigated cytokine Quantitative Trait Loci (cQTLs) of IL-6 responses to bacteria and identified nine (eight novel) loci. Our integrative approach describing stimuli, cytokines and children as variables revealed robust immunologically and microbiologically plausible clustering, providing a framework for a greater understanding of host-responses to infection, including novel genetic associations with respiratory disease.

The position of geochemical variables as causal co-factors of diseases of unknown aetiology

Abstract

The term diseases of unknown aetiology (DUA) or idiopathic diseases is used to describe diseases that are of uncertain or unknown cause or origin. Among plausible geoenvironmental co-factors in causation of DUA, this article focusses on the entry of trace elements, including metals and metalloids into humans, and their involvement in humoral and cellular immune responses, representing potentially toxic agents with implications as co-factors for certain DUA. Several trace elements/metals/metalloids (micronutrients) play vital roles as co-factors for essential enzymes and antioxidant molecules, thus, conferring protection against disease. However, inborn errors of trace element/metal/metalloid metabolisms can occur to produce toxicity, such as when there are basic defects in the element transport mechanism. Ultimately, it is the amount of trace element, metal or metalloid that is taken up, its mode of accumulation in human tissues, and related geomedical attributes such as the chemical form and bioavailability that decisively determine whether the exerted effects are toxic or beneficial. Several case descriptions of DUA that are common worldwide are given to illustrate our knowledge so far of how trace element/metal/metalloid interactions in the immune system may engender its dysregulation and be implicated as causal co-factors of DUA.

Article highlights

The importance of a proper understanding of geochemical perturbations in human metabolisms is emphasisedIt is proferred that such an understanding would aid greatly in the decipherment of diseases of unknown aetiology (DUA)The thesis presented may pave the way towards better diagnosis and therapy of DUA.

Infants Hospitalized with Lower Respiratory Tract Infections Were More Likely to Develop Asthma

Introduction: Lower respiratory tract infections (LRTIs) have been reported to possibly initiate the development of asthma in children. However, the role of LRTIs in infantile asthma remains controversial. The goal of this study is to investigate whether LRTIs in hospitalized infants are involved in the development of asthma. Materials and Methods: The subjects were 251 infants under 2 years of age who were admitted to our hospital with an RTI (59 cases of upper RTI (URTIs) with upper respiratory tract inflammation and pharyngeal tonsillitis; 192 cases of LRTIs with bronchitis, pneumonia, and bronchiolitis). Pathogens of viral infections were examined at admission using viral antigen test kits that could be used in ordinary clinical practice in Japan. When the children reached the age of 3 years, a survey was conducted by mailing a questionnaire to determine the symptoms, diagnosis, and treatment of asthma. Results: The mailed questionnaires were returned by 116 of the 251 subjects. On the questionnaire, the diagnosis of asthma and treatment for asthma were significantly higher in hospitalized infants with LRTIs than in those with URTIs. By diagnosis of LRTIs, infants with pneumonia and bronchiolitis were significantly more likely to develop asthma. However, on pathogen-specific examination, there was no difference in the development of asthma among infants with LRTIs. Conclusion: LRTI in infancy may be involved in the development of asthma. The severity of LRTI in hospitalized infants, but not the particular viral pathogen causing infection, may be associated with later asthma onset.

Identifying socio-ecological drivers of common cold in Bhutan: a national surveillance data analysis

The common cold is a leading cause of morbidity and contributes significantly to the health costs in Bhutan. The study utilized multivariate Zero-inflated Poisson regression in a Bayesian framework to identify climatic variability and spatial and temporal patterns of the common cold in Bhutan. There were 2,480,509 notifications of common cold between 2010 and 2018. Children aged < 15 years were twice (95% credible interval [CrI] 2.2, 2.5) as likely to get common cold than adults, and males were 12.4% (95 CrI 5.5%, 18.7%) less likely to get common cold than females. A 10 mm increase in rainfall lagged one month, and each 1 °C increase of maximum temperature was associated with a 5.1% (95% CrI 4.2%, 6.1%) and 2.6% (95% CrI 2.3%, 2.8%) increase in the risk of cold respectively. An increase in elevation of 100 m and 1% increase in relative humidity lagged three months were associated with a decrease in risk of common cold by 0.1% (95% CrI 0.1%, 0.2%) and 0.3% (95% CrI 0.2%, 0.3%) respectively. Seasonality and spatial heterogeneity can partly be explained by the association of common cold to climatic variables. There was statistically significant residual clustering after accounting for covariates. The finding highlights the influence of climatic variables on common cold and suggests that prioritizing control strategies for acute respiratory infection program to subdistricts and times of the year when climatic variables are associated with common cold may be an effective strategy.

Innate Immune Responses by Respiratory Viruses, Including Rhinovirus, During Asthma Exacerbation

Viral infection, especially with rhinovirus (RV), is a major cause of asthma exacerbation. The production of anti-viral cytokines such as interferon (IFN)-β and IFN-α from epithelial cells or dendritic cells is lower in patients with asthma or those with high IgE, which can contribute to viral-induced exacerbated disease in these patients. As for virus-related factors, RV species C (RV-C) induces more exacerbated disease than other RVs, including RV-B. Neutrophils activated by viral infection can induce eosinophilic airway inflammation through different mechanisms. Furthermore, virus-induced or virus-related proteins can directly activate eosinophils. For example, CXCL10, which is upregulated during viral infection, activates eosinophils in vitro. The role of innate immune responses, especially type-2 innate lymphoid cells (ILC2) and epithelial cell-related cytokines including IL-33, IL-25, and thymic stromal lymphopoietin (TSLP), in the development of viral-induced airway inflammation has recently been established. For example, RV infection induces the expression of IL-33 or IL-25, or increases the ratio of ILC2 in the asthmatic airway, which is correlated with the severity of exacerbation. A mouse model has further demonstrated that virus-induced mucous metaplasia and ILC2 expansion are suppressed by antagonizing or deleting IL-33, IL-25, or TSLP. For treatment, IFNs including IFN-β suppress not only viral replication but also ILC2 activation in vitro. Agonists of toll-like receptor (TLR) 3 or 7 can induce IFNs, which can then suppress viral replication and ILC2 activation. Therefore, if delivered in the airway, IFNs or TLR agonists could become innovative treatments for virus-induced asthma exacerbation.

A Pandemic Lesson for Global Lung Diseases: Exacerbations Are Preventable

A dramatic global reduction in the incidence of common seasonal respiratory viral infections has resulted from measures to limit the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the pandemic. This has been accompanied by falls reaching 50% internationally in the incidence of acute exacerbations of preexisting chronic respiratory diseases that include asthma, chronic obstructive pulmonary disease, and cystic fibrosis. At the same time, the incidence of acute bacterial pneumonia and sepsis has fallen steeply worldwide. Such findings demonstrate the profound impact of common respiratory viruses on the course of these global illnesses. Reduced transmission of common respiratory bacterial pathogens and their interactions with viruses appear also as central factors. This review summarizes pandemic changes in exacerbation rates of asthma, chronic obstructive pulmonary disease, cystic fibrosis, and pneumonia. We draw attention to the substantial body of knowledge about respiratory virus infections in these conditions, and that it has not yet translated into clinical practice. Now that the large scale of benefits that could be gained by managing these pathogens is unmistakable, we suggest that the field merits substantial academic and industrial investment. We consider how pandemic-inspired measures for prevention and treatment of common infections should become a cornerstone for managing respiratory diseases.

Risk Factors and Outcomes Associated With Antibiotic Therapy in Children Hospitalized With Asthma Exacerbation

OBJECTIVE

Despite lack of benefit, antibiotics are overused in management of asthma exacerbation in children. In this study, data from a single children's hospital were analyzed to identify factors and outcomes associated with antibiotic use in children hospitalized with asthma.

METHODS

The study population was identified by using administrative data from 2012 to 2015, with subsequent verification of asthma. We analyzed factors associated with antibiotic use (demographic, seasonal, clinical) and outcome (length of stay [LOS]) with respect to: 1) disposition to pediatric floor (PF) or pediatric intensive care unit (PICU); and 2) evidence of coexisting bacterial infection and/or fever. Statistical analysis included univariate and controlled regression models. Data are presented as median and IQR for continuous variables and OR and regression coefficient (β) with 95% CIs for regression analyses.

RESULTS

Of 600 patients, 28.8% were admitted to PICU, 14.8% had verified bacterial infection, and 53.8% received antibiotic, mainly azithromycin. Nearly all PICU patients were treated with antibiotic, irrespective of coexisting bacterial infection or fever. Among PF patients, nearly 30% without bacterial infection or fever and 40% with fever alone received antimicrobials. Overall risk for antibiotic treatment was associated with older age, female sex, desaturation events, oxygen supplementation, and PICU admission. Additionally, antibiotic treatment was associated with 13- to 19-hour increased LOS for PF patients without bacterial infection and/or fever.

CONCLUSIONS

Almost half of pediatric patients admitted with asthma exacerbation received antibiotic therapy with no clear indication, which was associated with prolonged LOS.

Lower viral loads in subjects with rhinovirus-challenged allergy despite reduced innate immunity

BACKGROUND

Viral infections, especially those caused by rhinovirus, are the most common cause of asthma exacerbations. Previous studies have argued that impaired innate antiviral immunity and, as a consequence, more severe infections contribute to these exacerbations.

OBJECTIVE

These studies explored the innate immune response in the upper airway of volunteers with allergic rhinitis and asthma in comparison to healthy controls and interrogated how these differences corresponded to severity of infection.

METHODS

Volunteers with allergic rhinitis, those with asthma, and those who are healthy were inoculated with rhinovirus A16 and monitored for clinical symptoms. Tissue and nasal wash samples were evaluated for antiviral signature and viral load.

RESULTS

Both subjects with allergic rhinitis and asthma were found to have more severe cold symptoms. Subjects with asthma had worsened asthma control and increased bronchial hyperreactivity in the setting of higher fractional exhaled breath nitric oxide and blood eosinophils. These studies confirmed reduced expression of interferons and virus-specific pattern recognition receptors in both cohorts with atopy. Nevertheless, despite this defect in innate immunity, volunteers with allergic rhinitis/asthma had reduced rhinovirus concentrations in comparison to the controls.

CONCLUSION

These results confirm that the presence of an allergic inflammatory disorder of the airway is associated with reduced innate immune responsive to rhinovirus infection. Despite this, these volunteers with allergy have reduced viral loads, arguing for the presence of a compensatory mechanism to clear the infection.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02910401.

Roles of Nucleoporin RanBP2/Nup358 in Acute Necrotizing Encephalopathy Type 1 (ANE1) and Viral Infection

Ran Binding Protein 2 (RanBP2 or Nucleoporin358) is one of the main components of the cytoplasmic filaments of the nuclear pore complex. Mutations in the RANBP2 gene are associated with acute necrotizing encephalopathy type 1 (ANE1), a rare condition where patients experience a sharp rise in cytokine production in response to viral infection and undergo hyperinflammation, seizures, coma, and a high rate of mortality. Despite this, it remains unclear howRanBP2 and its ANE1-associated mutations contribute to pathology. Mounting evidence has shown that RanBP2 interacts with distinct viruses to regulate viral infection. In addition, RanBP2 may regulate innate immune response pathways. This review summarizes recent advances in our understanding of how mutations in RANBP2 contribute to ANE1 and discusses how RanBP2 interacts with distinct viruses and affects viral infection. Recent findings indicate that RanBP2 might be an important therapeutic target, not only in the suppression of ANE1-driven cytokine storms, but also to combat hyperinflammation in response to viral infections.

Human rhinovirus promotes STING trafficking to replication organelles to promote viral replication

Human rhinovirus (HRV), like coronavirus (HCoV), are positive-strand RNA viruses that cause both upper and lower respiratory tract illness, with their replication facilitated by concentrating RNA-synthesizing machinery in intracellular compartments made of modified host membranes, referred to as replication organelles (ROs). Here we report a non-canonical, essential function for stimulator of interferon genes (STING) during HRV infections. While the canonical function of STING is to detect cytosolic DNA and activate inflammatory responses, HRV infection triggers the release of STIM1-bound STING in the ER by lowering Ca²⁺, thereby allowing STING to interact with phosphatidylinositol 4-phosphate (PI4P) and traffic to ROs to facilitates viral replication and transmission via autophagy. Our results thus hint a critical function of STING in HRV viral replication and transmission, with possible implications for other RO-mediated RNA viruses.

Evidence exists that the typically antiviral signaling mediator STING is, counterintuitively, needed for optimal human rhinovirus infection. Here the authors confirm this finding and show how human rhinovirus can reduce stored Ca2⁺ levels to drive this effect.

The Effect of Anti-Chemokine Oral Drug XC8 on Cough Triggered by The Agonists of TRPA1 But Not TRPV1 Channels in Guinea Pigs

Introduction

Chronic cough heavily affects patients’ quality of life, and there are no effective licensed therapies available. Cough is a complication of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infection, asthma, and other diseases. Patients with various diseases have a different profile of tussive responses to diverse cough triggers, thereby suggesting sundry mechanisms of neuronal dysfunctions. Previously, we demonstrated that the small molecule drug XC8 shows a clinical anti-asthmatic effect. The objective of the present study was to investigate the effect of XC8 on cough.

Methods

We studied the antitussive effect of XC8 on cough induced by agonists activating human transient receptor potential (TRP) cation channels TRPA1 or TRPV1 in guinea pigs. We checked the agonistic/antagonistic activity of XC8 on the human cation channels TRPA1, TRPV1, TRPM8, P2X purinoceptor 2 (P2X2), and human acid sensing ion channel 3 (hASIC3) in Fluorescent Imaging Plate Reader (FLIPR) assay.

Results

XC8 demonstrated clear antitussive activity and dose-dependently inhibited cough in guinea pigs induced by citric acid alone (up to 67.1%) or in combination with IFN-γ (up to 76.4%). XC8 suppressed cough reflexes induced by the repeated inhalation of citric acid (up to 80%) or by cinnamaldehyde (up to 60%). No activity of XC8 against cough evoked by capsaicin was revealed. No direct agonistic/antagonistic activity of XC8 on human TRPA1, TRPV1, TRPM8, P2X2, or hASIC3 was detected.

Conclusions

XC8 acts against cough evoked by the activation of TRPA1 (citric acid/cinnamaldehyde) but not TRPV1 (capsaicin) channels. XC8 inhibits the cough reflex and suppresses the cough potentiation by IFN-γ. XC8 might be of significant therapeutic value for patients suffering from chronic cough associated with inflammation.

Impact of COVID-19 on people with asthma: a mixed methods analysis from a UK wide survey

INTRODUCTION

The impact of acute COVID-19 on people with asthma appears complex, being moderated by multiple interacting disease-specific, demographic and environmental factors. Research regarding longer-term effects in this group is limited. We aimed to assess impacts of COVID-19 and predictors of persistent symptoms, in people with asthma.

METHODS

Using data from an online UK-wide survey of 4500 people with asthma (median age 50-59 years, 81% female), conducted in October 2020, we undertook a mixed methods analysis of the characteristics and experience of those reporting having had COVID-19.

RESULTS

The COVID-19 group (n=471, 10.5%) reported increased inhaler use and worse asthma management, compared with those not reporting COVID-19, but did not differ by gender, ethnicity or household income. Among the COVID-19 group, 56.1% reported having long COVID, 20.2% were 'unsure'. Those with long COVID were more likely than those without long COVID to describe: their breathing as worse or much worse after their initial illness (73.7% vs 34.8%, p<0.001), increased inhaler use (67.8% vs 34.8%, p<0.001) and worse or much worse asthma management (59.6% vs 25.6%, p<0.001). Having long COVID was not associated with age, gender, ethnicity, UK nation or household income.Analysis of free text survey responses identified three key themes: (1) variable COVID-19 severity, duration and recovery; (2) symptom overlap and interaction between COVID-19 and asthma; (3) barriers to accessing healthcare.

CONCLUSIONS

Persisting symptoms are common in people with asthma following COVID-19. Measures are needed to ensure appropriate healthcare access including clinical evaluation and investigation, to distinguish between COVID-19 symptoms and asthma.

Epidemiology and Clinical Characteristics of Human Coronaviruses-Associated Infections in Children: A Multi-Center Study

BACKGROUND

Human coronaviruses (HCoVs) are associated with upper respiratory tract infections. Although studies have analyzed the clinical and epidemiological characteristics of HCoV-associated infections, no multi-center studies have been conducted in Korean children. We aimed to describe the epidemiology and clinical characteristics of HCoV-associated infection in children.

METHODS

We retrospectively reviewed medical records of children in whom HCoVs were detected using multiplex reverse transcriptase-polymerase chain reaction amplification in five centers from January 2015 to December 2019.

RESULTS

Overall, 1,096 patients were enrolled. Among them, 654 (59.7%) patients were male. The median age was 1 year [interquartile range (IQR), 0-2 years]. HCoVs were identified mainly in winter (55.9%). HCoV-229E, HCoV-OC43, and HCoOV-NL63 were detected mainly in winter (70.9, 55.8, and 57.4%, respectively), but HCoV-HKU1 was mainly identified in spring (69.7%). HCoV-OC43 (66.0%) was detected most frequently, followed by HCoV-NL63 (33.3%), and HCoV-229E (7.7%). Two different types of HCoVs were co-detected in 18 samples, namely. Alphacoronavirus-betacoronavirus co-infection (n = 13) and, alphacoronavirus-alphacoronavirus co-infection (n = 5). No betacoronavirus-betacoronavirus co-infection was detected. Patients were diagnosed with upper respiratory tract infection (41.4%), pneumonia (16.6%), acute bronchiolitis (15.5%), non-specific febrile illness (13.1%), croup (7.3%), and acute gastroenteritis (5.1%). There were 832 (75.9%) hospitalized patients with a median duration of hospitalization of 4 days (IQR, 3-5 days); 108 (9.9%) patients needed supplemental oxygen with 37 (3.4%) needing high-flow nasal cannula or mechanical ventilation. There were no deaths.

CONCLUSION

HCoV-associated infections exhibit marked seasonality with peaks in winter. Patients with lower respiratory tract infection, a history of prematurity, or underlying chronic diseases may progress to a severe course and may need oxygen therapy.

Infection with SARS-CoV-2 among children with asthma: evidence from Global Asthma Network

BACKGROUND

Clinical presentations of coronavirus disease 2019 (COVID-19) among children with asthma have rarely been investigated. This study aimed to assess clinical manifestations and outcome of COVID-19 among children with asthma, and whether the use of asthma medications was associated with outcomes of interest.

METHODS

The Global Asthma Network (GAN) conducted a global survey among GAN centers. Data collection was between November 2020 and April 2021.

RESULTS

Fourteen GAN centers from 10 countries provided data on 169 children with asthma infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 was asymptomatic in 58 (34.3%), mild in 93 (55.0%), moderate in 14 (8.3%), and severe/critical in 4 (2.4%). Thirty-eight (22.5%) patients had exacerbation of asthma and 21 (12.4%) were hospitalized for a median of 7 days (interquartile range 3-16). Those who had moderate or more severe COVID-19 were significantly more likely to have exacerbation of asthma as compared to those who were asymptomatic or had mild COVID-19 (adjusted odds ratio (adjOR) 3.97, 95% CI 1.23-12.84). Those who used inhaled bronchodilators were significantly more likely to have a change of asthma medications (adjOR 2.39, 95% CI 1.02-5.63) compared to those who did not. Children who used inhaled corticosteroids (ICS) did not differ from those who did not use ICS with regard to being symptomatic, severity of COVID-19, asthma exacerbation, and hospitalization.

CONCLUSIONS

Over dependence on inhaled bronchodilator may be inappropriate. Use of ICS may be safe and should be continued in children with asthma during the pandemic of COVID-19.