Association of respiratory allergy, asthma, and expression of the SARS-CoV-2 receptor ACE2

Asthma and COVID-19: Unveiling Outcome Disparities and Treatment Impact Based on Distinct Endotypes

Rationale: Epidemiologic studies on patients with asthma and in vitro data suggest a protective role of type 2 (T2) inflammation in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Objectives: Using a large, multisite cohort, we studied clinical outcomes after SARS-CoV-2 infection in multiple asthma endotypes and examined the effects of T2-directed biologics in infected patients with asthma. Methods: The National COVID Cohort Collaborative Data Enclave was used to identify and stratify patients with asthma by endotype to include those with non-T2 and T2 asthma, as well as exposure to T2-directed biologic therapy. We evaluated the risk of hospitalization, invasive mechanical ventilation, and 90-day mortality by endotype and exposure to biologics. Results: For this study, 402,376 patients met the inclusion criteria, of whom 138,142 (34%) were characterized as having non-T2 asthma and 264,234 (66%) as having T2 asthma, a group further divided into 104,823 (26%) atopic, 84,440 (21%) eosinophilic, and 74,971 (19%) T2-high asthmatic endotypes. Compared with patients with non-T2 asthma, those with atopic and T2-high asthma experienced decreased odds of hospitalization and 90-day mortality. Conversely, patients with eosinophilic asthma experienced higher odds of hospitalization, intubation, and 90-day mortality. Exposure to T2-directed biologic therapies did not alter outcomes after propensity score matching. In contrast, maximum eosinophil count and recent systemic corticosteroid use were directly correlated with increased odds of all outcomes. Conclusions: Coronavirus disease (COVID-19) outcomes differ depending on asthma endotype, with patients with atopic asthma experiencing lower odds and those with eosinophilic asthma experiencing higher odds of deleterious outcomes. T2-directed biologic treatment did not alter these outcomes, but recent systemic corticosteroid use predisposes all patients with asthma to adverse outcomes.

Exploring Asthma as a Protective Factor in COVID-19 Outcomes

Asthma has long been associated with increased susceptibility to viral respiratory infections, leading to significant exacerbations and poorer clinical outcomes. Contrarily and interestingly, emerging data and research surrounding the COVID-19 pandemic have shown that patients with asthma infected with SARS-CoV-2 experienced decreased severity of disease, lower hospitalization rates, as well as decreased morbidity and mortality. Research has shown that eosinophils could enhance immune defense against viral infections, while inhaled corticosteroids can assist in controlling systematic inflammation. Moreover, reduced ACE-2 expression in individuals with asthma may restrict viral entry, and the Th2 immune response may offset the Th1 response typically observed in severe COVID-19 patients. These factors may help explain the favorable outcomes seen in asthmatic patients during the COVID-19 pandemic. This review highlights potential protective mechanisms seen in asthmatic patients, including eosinophilia, the use of inhaled corticosteroids, reduced ACE-2 expression, and a dominate Th2 immune response. Such a study will be helpful to better manage patients with asthma who have contracted COVID-19.

Serum TARC Level as a Predictive Marker of Severe Disease in COVID-19 during the Omicron Variant Period of the Pandemic

Objective Thymus and activation-regulated chemokine (TARC) can predict severe disease in patients with coronavirus disease 2019 (COVID-19). However, no reports have addressed the predictive value of TARC with the widespread use of vaccines and medications for COVID-19 during the Omicron variant period of the pandemic. Methods This single-center prospective cohort study enrolled COVID-19 patients admitted to our institution between December 1, 2021, and August 15, 2022. Patients with respiratory failure due to diseases other than COVID-19 were also excluded. We measured the serum TARC levels of patients at admission. Results We enrolled 157 patients, with 89 in the severe group and 68 in the non-severe group. The severe group was more likely than the non-severe group to include older patients, those with no or one dose of vaccine, and those with interstitial lung disease. The cutoff level of TARC derived from a receiver operator characteristic curve analysis to predict severe disease was 174.0 pg/mL. The sensitivity, specificity, positive predictive value, and negative predictive value were 72.1%, 69.7%, 64.5%, and 76.5%, respectively. The area under the curve was 0.722 (95% confidence interval: 0.635-0.809). A multivariate analysis showed that 2 vaccination doses were associated with non-severe disease, and TARC ≤174 pg/mL was associated with severe disease. Conclusion TARC was a predictive factor for severe disease, but its cutoff value was higher and its predictive accuracy lower than those in previous reports. We surmised that during the Omicron variant period of the pandemic, the widespread use of vaccines and medications for COVID-19 decreased the predictive accuracy of TARC.

Determinants of persistence and recovery of chronic coronavirus disease 2019 chemosensory dysfunction

BACKGROUND

In 2% to 4% of patients, coronavirus disease 2019 (COVID-19) chemosensory dysfunction (CSD) persists beyond 6 months, accounting for up to 4 million people in the United States. The predictors of persistence and recovery require further exploration.

OBJECTIVE

We sought to define the predictors of recovery and assess the quality of CSD in registry subjects with self-reported persistent smell and taste dysfunction after COVID-19.

METHODS

COVID-19 CSD participants (n = 408) from the 4 major waves of the pandemic completed questionnaires at 4 time points between 2021 and 2023, assessing demographics, sinonasal symptoms, and self-assessed recovery. Objective measurements of smell (UPSIT) and taste (BWETT) were performed on a subcohort (n = 108).

RESULTS

In this chronic CSD cohort, the average symptom duration was 24 ± 5 months, with 70% of those who contracted COVID-19 in 2020 report ongoing dysfunction. Phantosmia and dysgeusia were most prevalent in the early waves of COVID-19, while most participants reported disrupted ability to distinguish scents and flavors as well as undulating chemosensory function. Subjects reported low incidence of subjective sinonasal symptoms but high prevalence of sleep and mood disturbance. Cigarette smoke phantosmia was predictive of persistence of CSD. Conversely, self-reported environmental allergies and hypertension were predictive of recovery, and dust mite allergies specifically were negative predictors of cigarette smoke phantosmia. Finally, no treatment resolved CSD, but nasal steroids were reported to be effective by recovered CSD subjects. Objective measures of both smell and taste were significantly reduced in patients with chronic CSD compared to controls.

CONCLUSIONS

Chronic COVID-19 CSD is a syndrome resistant to standard anti-inflammatory therapy. Preexisting environmental allergies and hypertension predict recovery, while cigarette smoke phantosmia predicts persistence.

Risk and protective factors for coronavirus disease 2019 (COVID-19) in allergic rhinitis patients: a national survey in China

Background

Several epidemiological studies have shown that allergic rhinitis (AR) patients are more susceptible to coronavirus disease 2019 (COVID-19).

Objective

We aim to investigate the risk factors for COVID-19 in AR patients.

Methods

A retrospective nationwide cohort study was conducted based on a questionnaire survey in China. The baseline characteristics, region of residence, smoking and drinking status, comorbidities, vaccination status and previous infection information were obtained. Allergen test results, the SARS-CoV-2 nucleic acid test, and antigen detection results were collected. Information on AR and comorbid medication use pre-SARS-CoV-2 infection was also collected. Binary logistic regression and analysis of covariance (different adjusted models) were conducted.

Results

In all, 830 AR patients were included; 627 patients (75.54%) were infected with SARS-CoV-2. AR comorbid with allergic conjunctivitis (AC) was a protective factor [OR: 0.525 (95% CI = 0.296-0.929), P = 0.027] against SARS-CoV-2 infection, while AR comorbid with food allergy was a risk factor [OR: 6.404 (95% CI = 1.349-30.402), P = 0.0195]. Although fewer patients received four doses of the vaccine, the results showed a significant protective effect against SARS-CoV-2 infection in AR patients [OR: 0.093 (95% CI = 0.025-0.348), P = 0.0004]. Underweight was a protective factor against COVID-19 [OR: 0.287 (95% CI = 0.147-0.562), P = 0.0003] after full multivariable adjustment. Overweight was associated with a 2.071-fold higher risk for COVID-19 compared with normal weight [(95% CI = 1.045-4.105), P = 0.0370]. Additionally, house dust mite (HDM)-specific allergies were also protective against COVID-19 [OR: 0.537 (95% CI = 0.290-0.996), P = 0.0484].

Conclusions

This study revealed underlying protective and risk factors, which might be used to improve the management of AR and COVID-19.

Effects of nonpharmaceutical interventions during COVID-19 pandemic on pediatric asthma exacerbations and viral infections

Background

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in March 2020 led to the implementation of nonpharmaceutical interventions (NPIs) to curb its spread. Studies have shown that adult asthma exacerbations and viral infections decreased during NPI use. However, few studies have shown the effects of NPIs on pediatric asthma exacerbations and infections during and after the pandemic.

Objective

This study aimed to understand the impact of NPIs on asthma exacerbations and viral respiratory infections in pediatric patients at our institution from March 2018 to December 2022.

Methods

The medical record numbers of children with asthma exacerbations seen at our institution between March 2018 and December 2022 were analyzed. Subjects were categorized on the basis of timing of their exacerbation in relation to NPI enforcement. We used the results from clinical testing with the BioFire Respiratory Panel (BRP) to detect up to 22 respiratory pathogens and then correlated these results with asthma exacerbation severity.

Results

There were 5,758 asthma exacerbations recorded, with a 50% decline in average weekly exacerbations during NPI enforcement. Of the 70,682 BRP tests performed, 87% returned a positive result for at least 1 pathogen. Several viruses (respiratory syncytial virus, parainfluenza, and influenza) had a decrease in positivity rate with NPIs, whereas rhinovirus/enterovirus positivity rates were unchanged throughout the pandemic. Asthma exacerbations with a positive BRP result required higher clinical levels of care during the admission.

Conclusion

NPIs were associated with significantly reduced numbers of asthma exacerbations and respiratory viral infections. The post-NPI period saw a return to prepandemic levels of asthma exacerbations and an unusual surge in respiratory syncytial virus infections, emphasizing the need for continuous monitoring and adaptive strategies in the postpandemic landscape.

Recent insights into the impacts of COVID-19 on pediatric asthma

INTRODUCTION

The emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and the subsequent coronavirus disease 2019 (COVID-19) pandemic has raised questions about its impact on pediatric asthma. This review analyzes the latest research to offer a comprehensive understanding of the dynamics between COVID-19 and pediatric asthma.

AREAS COVERED

This narrative review examines the effects of COVID-19 on pediatric asthma, exploring clinical outcomes, immune responses, recommended treatments, the impact of SARS-CoV-2 strains, and COVID-19 vaccination. Data were sourced from databases (PubMed, Embase, and BioRxiv/MedRxiv) from January 2020 to November 2023.

EXPERT OPINION

In response to the COVID-19 pandemic, the international scientific community rapidly developed extensive knowledge, demonstrating unprecedented cooperation. Despite these advances, questions remain about SARS-CoV-2 infection and pediatric asthma. Most research consists of epidemiological studies with varying methods, sometimes yielding contradictory results. While asthma generally did not increase the risk of severe COVID-19 in children, uncontrolled asthma was a risk factor, highlighting the importance of maintaining asthma management. Telemedicine has proven effective for asthma control and will continue to grow, despite its limitations. Notably, allergic asthma may have a protective role against severe COVID-19. We recommend COVID-19 vaccination in the pediatric age group, including those with asthma.

Risk factors for severe outcomes of coronavirus disease 2019 through the waves of the pandemic: Comparing patients with and without solid organ transplantation

BACKGROUND

While coronavirus disease 2019 (COVID-19) is no longer a public health emergency, certain patients remain at risk of severe outcomes. To better understand changing risk profiles, we studied the risk factors for patients with and without solid organ transplantation (SOT) through the various waves of the pandemic.

METHODS

Using the National COVID Cohort Collaborative we studied a cohort of adult patients testing positive for COVID-19 between January 1, 2020, and May 2, 2022. We separated the data into waves of COVID-19 as defined by the Centers for Disease Control. In our primary outcome, we used multivariable survival analysis to look at various risk factors for hospitalization in those with and without SOT.

RESULTS

A total of 3,570,032 patients were captured. We found an overall risk attenuation of adverse COVID-19-associated outcomes over time. In both non-SOT and SOT populations, diabetes, chronic kidney disease, and congestive heart failure were risk factors for hospitalization. For SOT specifically, longer time periods between transplant and COVID-19 were protective and age was a risk factor. Notably, asthma was not a risk factor for major adverse renal cardiovascular events, hospitalization, or mortality in either group.

CONCLUSIONS

Our study provides a longitudinal view of the risks associated with adverse COVID-related outcomes amongst SOT and non-SOT patients, and how these risk factors evolved over time. Our work will help inform providers and policymakers to better target high-risk patients.

Rhinovirus infection of airway epithelial cells uncovers the non-ciliated subset as a likely driver of genetic risk to childhood-onset asthma

Asthma is a complex disease caused by genetic and environmental factors. Studies show that wheezing during rhinovirus infection correlates with childhood asthma development. Over 150 non-coding risk variants for asthma have been identified, many affecting gene regulation in T cells, but the effects of most risk variants remain unknown. We hypothesized that airway epithelial cells could also mediate genetic susceptibility to asthma given they are the first line of defense against respiratory viruses and allergens. We integrated genetic data with transcriptomics of airway epithelial cells subject to different stimuli. We demonstrate that rhinovirus infection significantly upregulates childhood-onset asthma-associated genes, particularly in non-ciliated cells. This enrichment is also observed with influenza infection but not with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or cytokine activation. Overall, our results suggest that rhinovirus infection is an environmental factor that interacts with genetic risk factors through non-ciliated airway epithelial cells to drive childhood-onset asthma.

Differential regulation of viral entry-associated genes modulated by inflammatory cytokines in the nasal epithelium

This study aimed to investigate the impact of different types of nasal inflammation on the regulation of entry-associated genes of respiratory viruses, including severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), Middle East respiratory syndrome coronavirus (MERS-CoV), human coronavirus 229E (HCoV-229E), and influenza virus, in the nasal epithelium. Subjects were classified into three groups: control, eosinophilic chronic rhinosinusitis (ECRS), and noneosinophilic CRS (NECRS) groups. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2), alanyl aminopeptidase (ANPEP), dipeptidyl peptidase 4 (DPP4), and beta-galactoside alpha-2,6-sialyltransferase 1 (ST6GAL1), and beta-galactoside alpha-2,3-sialyltransferase 4 (ST3GAL4) were selected as key entry-associated genes for SARS-CoV-2, HCoV-229E, MERS-CoV, and influenza, respectively, and were evaluated. Brushing samples obtained from each group and human nasal epithelial cells cultured using an air-liquid interface system were treated for 7 days with typical inflammatory cytokines and analyzed using real-time polymerase chain reaction. Western blot analysis and confocal microscopy were performed. The entry-associated genes showed distinct regulation patterns in response to each interleukin-4 (IL-4), interleukin-13 (IL-13), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ). Specifically, ACE2 significantly decreased in type 2 cytokines (IL-4 and IL-13), while TMPRSS2 significantly decreased in type 1 cytokines (TNF-α and IFN-γ). ANPEP significantly decreased in both types of cytokines. Remarkably, DPP4 significantly increased in type 2 cytokines and decreased in type 1 cytokines. Moreover, ST6GAL1 and ST3GAL4 significantly increased in type 2 cytokines and decreased in type 1 cytokines, particularly IFN-γ. These findings were supported by western blot analysis and confocal imaging results, especially for ACE2 and DPP4. The findings regarding differential regulation suggest that patients with ECRS, primarily mediated by type 2 inflammation, may have lower susceptibility to SARS-CoV-2 and HCoV-229E infections but higher susceptibility to MERS-CoV and influenza infections.

Association between asthma and COVID-19 severity during Omicron epidemic: a retrospective cohort study using real-world data

BACKGROUND

The available evidence presented inconsistencies and inconclusive findings regarding the associations between co-existing asthma and mortality among COVID-19 patients. The objective of the current study is to investigate the relationship between asthma and severe outcomes after SARS-CoV-2 Omicron infection in an infection-naïve population.

METHODS

A retrospective cohort study using propensity score matching was conducted. The COVID-19 patients requiring hospitalisation in Hong Kong from January 1, 2022, to November 13, 2022, an Omicron-predominated period, were identified. Severe clinical outcomes were defined as ICU admission and inpatient death after the first positive PCR results as well as a composite outcome of both.

RESULTS

Of the 74,396 hospitalised COVID-19 patients admitted, 1,290 asthma patients and 18,641 non-asthma patients were included in the matched cohort. The rates of death and the composite outcome were 15·3% and 17·2%, respectively, among the non-asthma patients,12·2% and 13·6%, respectively, among the asthma patients, with adjusted hazard ratios equal to 0·775 (95% CI: 0·660-0·909) and 0·770 (95% CI: 0·662-0·895), respectively. The negative association was more apparent in the elderly and female groups. Asthma remained a factor that lowered the risk of disease severity even though the patients were not fully vaccinated with at least two doses.

CONCLUSIONS

We used real-world data to demonstrate that asthma was not a risk factor for COVID-19 severity of the infections of Omicron variant, even though the patients were not fully vaccinated.

Significant association between asthma and a lower risk of mortality among COVID-19 patients in Spain: A meta-analysis

Background

Various prevalences of asthma in coronavirus disease 2019 (COVID-19) have been reported in different regions, and the association between asthma and COVID-19 subsequent mortality has been in debate. Thus, this study aimed to investigate whether there was a significant association between asthma and COVID-19 mortality in Spain through a meta-analysis.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were strictly complied with conducting this study. The pooled odds ratio (OR) with a corresponding 95% confidence interval (CI) was calculated by a random-effects model. The I 2 statistics for heterogeneity, sensitivity analysis for robustness, Begg's test, and Egger's test for publication bias, along with subgroup analyses for confounding bias, were also performed to support the foundation of this study.

Results

The meta-analysis revealed that asthma was significantly associated with a lower risk of mortality among COVID-19 patients in Spain with a random-effects model (pooled OR = 0.78, 95% CI = 0.69-0.88, I 2 = 35%). Further subgroup analyses by male proportion and sample size also indicated that a statistically significant negative correlation did exist between asthma and COVID-19 mortality. Robustness and no publication on-bias were evidenced by sensitivity analysis, Egger's test, and Begg's test, respectively.

Conclusion

In conclusion, patients with asthma were found to have a lower risk of mortality from COVID-19 in Spain, especially among elderly patients. In addition, asthmatic patients infected with COVID-19 may be at risk of death compared to non-asthmatic patients, which is not a cause for undue concern, thereby reducing the burden of medication.

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.

Key Characteristics of Asthma Patients with COVID-19 Vary Substantially by Age

Introduction

Assessing COVID-19 risk in asthma patients is challenging due to disease heterogeneity and complexity. We hypothesized that potential risk factors for COVID-19 may differ among asthma age groups, hindering important insights when studied together.

Methods

We included a population-based cohort of asthma patients from the Swedish National Airway Register (SNAR) and linked to data from several national health registers. COVID-19 outcomes included infection, hospitalization, and death from Jan 2020 until Feb 2021. Asthma patients were grouped by ages 12-17, 18-39, 40-64, and ≥65 years. Characteristics of asthma patients with different COVID-19 outcomes were compared with those in their age-corresponding respective source population.

Results

Among 201,140 asthma patients studied, 11.2% were aged 12-17 years, 26.4% 18-39, 37.6% 40-64, and 24.9% ≥65 years. We observed 18,048 (9.0%) COVID-19 infections, 2172 (1.1%) hospitalizations, and 336 (0.2%) COVID-19 deaths. Deaths occurred only among patients aged ≥40. When comparing COVID-19 cases to source asthma populations by age, large differences in potential risk factors emerged, mostly for COVID-19 hospitalizations and deaths. For ages 12-17, these included education, employment, autoimmune, psychiatric, and depressive conditions, and use of short-acting β-agonists (SABA) and inhaled corticosteroids (ICS). In the 18-39 age group, largest differences were for age, marital status, respiratory failure, anxiety, and body mass index. Ages 40-64 displayed notable differences for sex, birth region, cancer, oral corticosteroids, antihistamines, and smoking. For those aged ≥65, largest differences were observed for cardiovascular comorbidities, type 1 diabetes, chronic obstructive pulmonary disease, allergic conditions, and specific asthma treatments (ICS-SABA, ICS-long-acting bronchodilators (LABA)). Asthma control and lung function were important across all age groups.

Conclusion

We identify distinct differences in COVID-19-related risk factors among asthma patients of different ages. This information is essential for assessing COVID-19 risk in asthma patients and for tailoring patient care and public health strategies accordingly.

Association between allergic conditions and COVID-19 susceptibility and outcomes

BACKGROUND

The relationship between underlying type 2 inflammation and immune response to COVID-19 is unclear.

OBJECTIVE

To assess the relationships between allergic conditions and COVID-19 susceptibility and outcomes.

METHODS

In the Optum database, adult patients with and without major allergic conditions (asthma, atopic dermatitis [AD], allergic rhinitis, food allergy, anaphylaxis, or eosinophilic esophagitis) and patients with and without severe asthma/AD were identified. Adjusted incidence rate ratios for COVID-19 were compared among patients with vs without allergic conditions or severe asthma/AD vs non-severe asthma/AD during April 1, 2020, to December 31, 2020. Among patients with COVID-19, adjusted hazard ratios (aHRs) of 30-day COVID-19-related hospitalization/all-cause mortality were estimated for the same comparisons during April 1, 2020, to March 31, 2022.

RESULTS

Patients with (N = 1,273,231; asthma, 47.2%; AD, 1.5%; allergic rhinitis, 58.6%; food allergy, 5.1%; anaphylaxis, 4.1%; eosinophilic esophagitis, 0.9%) and without allergic conditions (N = 2,278,571) were identified. Allergic conditions (adjusted incidence rate ratios [95% CI], 1.22 [1.21-1.24]) and asthma severity (1.12 [1.09-1.15]) were associated with increased incidence of COVID-19. Among patients with COVID-19 (patients with [N = 261,076] and without allergic conditions [N = 1,098,135] were matched on age, sex, region, index month), having an allergic condition had minimal impact on 30-day COVID-19-related hospitalization/all-cause mortality (aHR [95% CI] 0.96 [0.95-0.98]) but was associated with a lower risk of mortality (0.80 [0.78-0.83]). Asthma was associated with a higher risk of COVID-19-related hospitalization/all-cause mortality vs non-asthma allergic conditions (aHR [95% CI], 1.27 [1.25-1.30]), mostly driven by higher hospitalization.

CONCLUSION

Allergic conditions were associated with an increased risk of receiving COVID-19 diagnosis but reduced mortality after infection.

Dynamic changes of nasal tight junctions in patients with convalescent COVID-19 with allergic rhinitis

KEY POINTS

Nasal tight junction module score correlates negatively to allergy module score in COVID-19. Omicron variant may slow-down tight junction restoration in patients with AR.

Respiratory allergic diseases and allergen immunotherapy: A French patient survey before and during the COVID-19 pandemic

Background

The COVID-19 pandemic brought unprecedented global disruption to both healthcare providers and patients with respiratory allergies. There are limited real-life data on the impact of the COVID-19 pandemic on the risk perception of patients with allergy treated with allergen immunotherapy (AIT).

Objective

To understand the risk perception of allergic patients treated with sublingual immunotherapy (SLIT) before and during the pandemic, and their attitudes towards COVID-19 infection and vaccination.

Methods

This was a non-interventional, cross-sectional survey conducted from October to November 2021 in France. Adult patients, who had been prescribed and had received a Stallergenes SLIT (liquid or liquid and tablets) before the pandemic (from August 1, 2018 to March 10, 2020) and during the pandemic (from March 11, 2020 to August 31, 2021), were identified from the Stallergenes named-patient products (NPP) database. Patients completed an online questionnaire. Data were analyzed descriptively.

Results

A total of 5258 patients from all over France completed the questionnaire. Mean (±SD) age of the respondents was 39.3 (±13.0) years and 66.9% were female. Some of them (11.8%) were obese (BMI >30 kg/m2). Main allergic diseases were rhinitis (80.0% of patients) with or without conjunctivitis, and asthma (39.0%). More than half of the patients experienced moderate to severe (58.0%) and persistent allergic rhinitis profile (70.4%). Most patients were poly-allergic (72.7%), mostly to house dust mites (61.9%), grass pollens (61.5%), tree pollens (57.8%), and cat dander (37.2%). Only 14.1% of patients experienced an aggravation of their allergy symptoms during lockdown and 14.8% were infected with COVID-19, with hospitalization required for 1.8%. Only 3.1% of patients reported their SLIT initiation as being postponed due to the pandemic. SLIT was changed, temporarily interrupted or permanently discontinued during the pandemic in 21.9% of patients. Changes mainly concerned the maintenance dose for SLIT-liquid (63.2%). SLIT modification was due to COVID-19 infection in only 4.2%. Most patients did not feel vulnerable (53.1%), anxious (55.2%), at risk to present severe symptoms of COVID-19 (77.1%), or at risk to transmit coronavirus (80.4%). However, greater anxiety was reported in patients with allergic asthma (33.6%) or other respiratory disorders (50.4%). Patients who felt vulnerable partly assigned their vulnerability to their allergic disease (59.3%). Suffering from an allergic disease did not make patients feel more vulnerable to side effects of COVID-19 vaccine for 79.6% of them.

Conclusion

Overall, most patients with allergy and under SLIT were not strongly concerned by the COVID-19 infection. SLIT did not have a negative impact on the COVID-19 symptoms.

Rhinovirus infection of airway epithelial cells uncovers the non-ciliated subset as a likely driver of genetic susceptibility to childhood-onset asthma

Asthma is a complex disease caused by genetic and environmental factors. Epidemiological studies have shown that in children, wheezing during rhinovirus infection (a cause of the common cold) is associated with asthma development during childhood. This has led scientists to hypothesize there could be a causal relationship between rhinovirus infection and asthma or that RV-induced wheezing identifies individuals at increased risk for asthma development. However, not all children who wheeze when they have a cold develop asthma. Genome-wide association studies (GWAS) have identified hundreds of genetic variants contributing to asthma susceptibility, with the vast majority of likely causal variants being non-coding. Integrative analyses with transcriptomic and epigenomic datasets have indicated that T cells drive asthma risk, which has been supported by mouse studies. However, the datasets ascertained in these integrative analyses lack airway epithelial cells. Furthermore, large-scale transcriptomic T cell studies have not identified the regulatory effects of most non-coding risk variants in asthma GWAS, indicating there could be additional cell types harboring these "missing regulatory effects". Given that airway epithelial cells are the first line of defense against rhinovirus, we hypothesized they could be mediators of genetic susceptibility to asthma. Here we integrate GWAS data with transcriptomic datasets of airway epithelial cells subject to stimuli that could induce activation states relevant to asthma. We demonstrate that epithelial cultures infected with rhinovirus significantly upregulate childhood-onset asthma-associated genes. We show that this upregulation occurs specifically in non-ciliated epithelial cells. This enrichment for genes in asthma risk loci, or 'asthma heritability enrichment' is also significant for epithelial genes upregulated with influenza infection, but not with SARS-CoV-2 infection or cytokine activation. Additionally, cells from patients with asthma showed a stronger heritability enrichment compared to cells from healthy individuals. Overall, our results suggest that rhinovirus infection is an environmental factor that interacts with genetic risk factors through non-ciliated airway epithelial cells to drive childhood-onset asthma.

SARS-CoV-2 seroprevalence and associated factors of infection before and after the Delta wave in French Polynesia: a cross-sectional study

BACKGROUND

French Polynesia (FP) comprises 75 inhabited islands scattered across five archipelagos. Between July and October 2021, the SARS-CoV-2 Delta variant triggered a much stronger second epidemic wave in FP than the original Wuhan strain, which was dominant from August 2020 to March 2021. Although previous seroprevalence surveys made it possible to determine the proportion of the population infected by SARS-CoV-2 on the two most populated islands (Tahiti and Moorea) after the first (20.6% in Tahiti and 9.4% in Moorea) and second (57.7% in Tahiti) epidemic waves, no data are available for more remote islands. We used blood samples and personal data collected before, during, and after the second wave from inhabitants of several islands within the five archipelagos to assess the prevalence of SARS-CoV-2 infections and identify associated factors.

METHODS

Blood samples and personal data were collected between April and December 2021 as part of the MATAEA study, a cross-sectional survey conducted on a random sample of the adult population representative of the five FP archipelagos and stratified by age and gender. IgG antibodies targeting the SARS-CoV-2 nucleocapsid (N) protein were detected using a recombinant antigen-based microsphere immunoassay. Factors associated with anti-SARS-CoV-2-N seropositivity were identified using logistic regression models.

RESULTS

Of 1,120 participants, 503 (44.9%) tested positive for anti-SARS-CoV-2-N antibodies, corresponding to a weighted prevalence of 56.8% for the FP population aged 18-69 years. The seroprevalence increased from 21.9% to 62.1% before and during/after the Delta wave. Of these infections, only 28.4% had been diagnosed by health professionals. The odds of being seropositive were lower in males, participants recruited before the Delta wave, those who had never been married, those with a diagnosed respiratory allergy, smokers, and those vaccinated against COVID-19.

CONCLUSIONS

Our results confirm the high impact of the Delta wave in FP. By the end of 2021, 56.8% of the FP population aged 18-69 years had been infected by SARS-CoV-2; the majority of these infections went undetected. Individuals with respiratory allergies were found to be less susceptible to SARS-CoV-2 infection.

The Frequency and Clinical Assessment of COVID-19 in Patients With Chronic Rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS), as an inflammatory airway disease, could be a risk factor for COVID-19 patients. This study aimed to investigate the frequency and severity of symptoms of COVID-19 in patients with CRS and to assess the association between the status of CRS symptoms and the quality of life (QoL) of the patients.

METHODS

In this observational and cross-sectional study, 207 adult CRS patients participated. The patients, who presented the symptoms of COVID-19, were examined by taking the reverse transcription-polymerase chain reaction test. A questionnaire was completed by each patient, regarding their demographic and clinical data. In addition, the GA2LEN and Sino-Nasal Outcome Test (SNOT-22) standard questionnaires were used to identify the comorbid allergic condition and QoL of CRS patients.

RESULTS

The frequency of patients with COVID-19 was 25 (12.1%) of which 22 were treated as outpatients, 2 of them admitted in wards and 1 at intensive care unit. The severity of hyposmia in the patients was 2 (8%) as mild, 5 (20%) moderate, and 11 (72%) as anosmia. The most common allergic and underlying comorbid diseases were allergic rhinitis (88%) and thyroid disorders (28%). Further, the average SNOT-22 score in 4 SNOT-22 domains (nasal, otologic, sleep, and emotional symptoms) was significantly decreased in CRS patients after a period of one year since the pandemic started (40.1 ± 18.0 vs. 46.3 ± 17.7; P < .0001).

DISCUSSION

This study showed a low frequency of COVID-19 in patients with CRS and about the same rate of infection positivity in the general population; therefore, we concluded that CRS could not be considered as a risk factor for COVID-19. Interestingly, the lower average score of SNOT-22 after one year of the pandemic in the patients with CRS confirmed the necessity for performing the standard health protocols by the patients.

Addressing adverse synergies between chemical and biological pollutants at schools-The 'SynAir-G' hypothesis

While the number and types of indoor air pollutants is rising, much is suspected but little is known about the impact of their potentially synergistic interactions, upon human health. Gases, particulate matter, organic compounds but also allergens and viruses, fall within the 'pollutant' definition. Distinct populations, such as children and allergy and asthma sufferers are highly susceptible, while a low socioeconomic background is a further susceptibility factor; however, no specific guidance is available. We spend most of our time indoors; for children, the school environment is of paramount importance and potentially amenable to intervention. The interactions between some pollutant classes have been studied. However, a lot is missing with respect to understanding interactions between specific pollutants of different classes in terms of concentrations, timing and sequence, to improve targeting and upgrade standards. SynAir-G is a European Commission-funded project aiming to reveal and quantify synergistic interactions between different pollutants affecting health, from mechanisms to real life, focusing on the school setting. It will develop a comprehensive and responsive multipollutant monitoring system, advance environmentally friendly interventions, and disseminate the generated knowledge to relevant stakeholders in accessible and actionable formats. The aim of this article it to put forward the SynAir-G hypothesis, and describe its background and objectives.

Mucosal Immunity against SARS-CoV-2 in the Respiratory Tract

The respiratory tract, the first-line defense, is constantly exposed to inhaled allergens, pollutants, and pathogens such as respiratory viruses. Emerging evidence has demonstrated that the coordination of innate and adaptive immune responses in the respiratory tract plays a crucial role in the protection against invading respiratory pathogens. Therefore, a better understanding of mucosal immunity in the airways is critical for the development of novel therapeutics and next-generation vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory viruses. Since the coronavirus disease 2019 pandemic, our knowledge of mucosal immune responses in the airways has expanded. In this review, we describe the latest knowledge regarding the key components of the mucosal immune system in the respiratory tract. In addition, we summarize the host immune responses in the upper and lower airways following SARS-CoV-2 infection and vaccination, and discuss the impact of allergic airway inflammation on mucosal immune responses against SARS-CoV-2.

A systematic two-sample and bidirectional MR process highlights a unidirectional genetic causal effect of allergic diseases on COVID-19 infection/severity

BACKGROUND

Allergic diseases (ADs) such as asthma are presumed risk factors for COVID-19 infection. However, recent observational studies suggest that the assumed correlation contradicts each other. We therefore systematically investigated the genetic causal correlations between various ADs and COVID-19 infection/severity.

METHODS

We performed a two-sample, bidirectional Mendelian randomization (MR) study for five types of ADs and the latest round of COVID-19 GWAS meta-analysis datasets (critically ill, hospitalized, and infection cases). We also further validated the significant causal correlations and elucidated the potential underlying molecular mechanisms.

RESULTS

With the most suitable MR method, asthma consistently demonstrated causal protective effects on critically ill and hospitalized COVID-19 cases (OR < 0.93, p < 2.01 × 10-2), which were further confirmed by another validated GWAS dataset (OR < 0.92, p < 4.22 × 10-3). In addition, our MR analyses also observed significant causal correlations of food allergies such as shrimp allergy with the risk of COVID-19 infection/severity. However, we did not find any significant causal effect of COVID-19 phenotypes on the risk of ADs. Regarding the underlying molecular mechanisms, not only multiple immune-related cells such as CD4+ T, CD8+ T and the ratio of CD4+/CD8+ T cells showed significant causal effects on COVID-19 phenotypes and various ADs, the hematology traits including monocytes were also significantly correlated with them. Conversely, various ADs such as asthma and shrimp allergy may be causally correlated with COVID-19 infection/severity by affecting multiple hematological traits and immune-related cells.

CONCLUSIONS

Our systematic and bidirectional MR analyses suggest a unidirectional causal effect of various ADs, particularly of asthma on COVID-19 infection/severity, but the reverse is not true. The potential underlying molecular mechanisms of the causal effects call for more attention to clinical monitoring of hematological cells/traits and may be beneficial in developing effective therapeutic strategies for allergic patients following infection with COVID-19.

The clinical course of hospitalized COVID-19 patients and aggravation risk prediction models: a retrospective, multi-center Korean cohort study

Background

Understanding the clinical course and pivotal time points of COVID-19 aggravation is critical for enhancing patient monitoring. This retrospective, multi-center cohort study aims to identify these significant time points and associate them with potential risk factors, leveraging data from a sizable cohort with mild-to-moderate symptoms upon admission.

Methods

This study included data from 1,696 COVID-19 patients with mild-to-moderate clinical severity upon admission across multiple hospitals in Daegu-Kyungpook Province (Daegu dataset) between February 18 and early March 2020 and 321 COVID-19 patients at Seoul Boramae Hospital (Boramae dataset) collected from February to July 2020. The approach involved: (1) identifying the optimal time point for aggravation using survival analyses with maximally selected rank statistics; (2) investigating the relationship between comorbidities and time to aggravation; and (3) developing prediction models through machine learning techniques. The models were validated internally among patients from the Daegu dataset and externally among patients from the Boramae dataset.

Results

The Daegu dataset showed a mean age of 51.0 ± 19.6 years, with 8 days for aggravation and day 5 being identified as the pivotal point for survival. Contrary to previous findings, specific comorbidities had no notable impact on aggravation patterns. Prediction models utilizing factors including age and chest X-ray infiltration demonstrated promising performance, with the top model achieving an AUC of 0.827 in external validation for 5 days aggravation prediction.

Conclusion

Our study highlights the crucial significance of the initial 5 days period post-admission in managing COVID-19 patients. The identification of this pivotal time frame, combined with our robust predictive models, provides valuable insights for early intervention strategies. This research underscores the potential of proactive monitoring and timely interventions in enhancing patient outcomes, particularly for those at risk of rapid aggravation. Our findings offer a meaningful contribution to understanding the COVID-19 clinical course and supporting healthcare providers in optimizing patient care and resource allocation.

Suppressed pediatric asthma hospitalizations during the COVID-19 pandemic in Japan, from a national survey

BACKGROUND

Acute asthma exacerbation in children is often caused by respiratory infections. In this study, a coordinated national surveillance system for acute asthma hospitalizations and causative respiratory infections was established. We herein report recent trends in pediatric acute asthma hospitalizations since the COVID-19 pandemic in Japan.

METHODS

Thirty-three sentinel hospitals in Japan registered all of their hospitalized pediatric asthma patients and their causal pathogens. The changes in acute asthma hospitalization in children before and after the onset of the COVID-19 pandemic and whether or not COVID-19 caused acute asthma exacerbation were investigated.

RESULTS

From fiscal years 2010-2019, the median number of acute asthma hospitalizations per year was 3524 (2462-4570), but in fiscal years 2020, 2021, and 2022, the numbers were 820, 1,001, and 1,026, respectively (the fiscal year in Japan is April to March). This decrease was observed in all age groups with the exception of the 3- to 6-year group. SARS-CoV-2 was evaluated in 2094 patients from fiscal years 2020-2022, but the first positive case was not detected until February 2022. Since then, only 36 of them have been identified with SARS-CoV-2, none of which required mechanical ventilation. Influenza, RS virus, and human metapneumovirus infections also decreased in FY 2020. In contrast, 24% of patients had not been receiving long-term control medications before admission despite the severity of bronchial asthma.

CONCLUSION

SARS-CoV-2 was hardly detected in children with acute asthma hospitalization during the COVID-19 pandemic. This result indicated that SARS-CoV-2 did not induce acute asthma exacerbation in children. Rather, infection control measures implemented against the pandemic may have consequently reduced other respiratory virus infections and thus acute asthma hospitalizations during this period. However, the fact that many hospitalized patients have not been receiving appropriate long-term control medications is a major problem that should be addressed.

Evaluation of immunogenicity-induced DNA vaccines against different SARS-CoV-2 variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in 2019 and caused the coronavirus disease 2019 (COVID-19) pandemic worldwide. As of September 2023, the number of confirmed coronavirus cases has reached over 770 million and caused nearly 7 million deaths. The World Health Organization assigned and informed the characterization of variants of concern (VOCs) to help control the COVID-19 pandemic through global monitoring of circulating viruses. Although many vaccines have been proposed, developing an effective vaccine against variants is still essential to reach the endemic stage of COVID-19. We designed five DNA vaccine candidates composed of the first isolated genotype and major SARS-CoV-2 strains from isolated Korean patients classified as VOCs, such as Alpha, Beta, Gamma, and Delta. To evaluate the immunogenicity of each genotype via homologous and heterologous vaccination, mice were immunized twice within a 3-week interval, and the blood and spleen were collected 1 week after the final vaccination to analyze the immune responses. The group vaccinated with DNA vaccine candidates based on the S genotype and the Alpha and Beta variants elicited both humoral and cellular immune responses, with higher total IgG levels and neutralizing antibody responses than the other groups. In particular, the vaccine candidate based on the Alpha variant induced a highly diverse cytokine response. Additionally, we found that the group subjected to homologous vaccination with the S genotype and heterologous vaccination with S/Alpha induced high total IgG levels and a neutralization antibody response. Homologous vaccination with the S genotype and heterologous vaccination with S/Alpha and S/Beta significantly induced IFN-γ immune responses. The immunogenicity after homologous vaccination with S and Alpha and heterologous vaccination with the S/Alpha candidate was better than that of the other groups, indicating the potential for developing novel DNA vaccines against different SARS-CoV-2 variants.

The SARS-CoV-2 pandemic and asthma: What we have learned and what is still unknown

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has brought new insights into the immunologic intricacies of asthma. In this review, we discuss the epidemiology of asthma in patients infected with SARS-CoV-2 and the risk of severe infection. Type 2 inflammation had an overall protective effect against SARS-CoV-2 infection by various mechanisms summarized in this review. Asthma, intranasal, and inhaled corticosteroids decreased the angiotensin-converting enzyme 2 receptor, an important receptor for SARS-CoV-2 entry into host cells. We summarize the nuances of the treatment of type 2 inflammation despite its underlying protective effects. Research to date has shown that patients on various allergen immunotherapies and biologics do benefit from being vaccinated.

Common Pollen Modulate Immune Responses against Viral-Like Challenges in Airway Coculture Model

Recent research indicates that exposure to pollen increases the risk and severity of respiratory infections, while studies also suggest that it may possess a protective function. Our aim was to investigate how exposure to common pollen modifies airway cells' responses to viral- or bacterial-like challenges and vice versa. Cocultured A549 and THP-1 cells were exposed to three doses of four different pollens (Alnus glutinosa, Betula pendula, Phleum pratense, or Ambrosia artemisiifolia) and subsequently to Toll-like receptor (TLR) ligands mimicking bacterial and viral challenges (TLR3, TLR4, TLR7/8). The stimulation experiment was replicated in reverse order. Toxicological and immunological end points were analyzed. When cells were primed with pollen, especially with grass (P. pratense) or weed (A. artemisiifolia), the ability of cells to secrete cytokines in response to bacterial- and viral-like exposure was decreased. In contrast, cells primed with viral ligand TLR7/8 showed greater cytokine responses against pollen than cells exposed to ligands or pollen alone. Our results suggest that pollen exposure potentially weakens immune reactions to bacterial- or viral-like challenges by modulating cytokine production. They also indicate that TLR7/8-mediated viral challenges could elicit exaggerated immune responses against pollen. Both mechanisms could contribute to the acceleration and complication of infections during the pollen season.

COVID-19 and Its Impact on Common Diseases in the Allergy Clinics

Coronavirus disease 2019 (COVID-19) is a highly contagious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has various effects on asthma, allergic rhinitis, atopic dermatitis, and urticaria and may change the course of the disease depending on the severity of the infection and control status of the disease. Conversely, these diseases may also impact the course of COVID-19. Patients with chronic urticaria and atopic dermatitis may have COVID-19-induced disease exacerbations and biological treatments reduce the risk of exacerbations. Poor asthma control is linked to severe COVID-19 while allergic asthma is associated with lower risk of death and a lower rate of hospitalization due to COVID-19 compared with nonallergic asthma. The use of intranasal corticosteroids is associated with lower rates of hospitalization due to COVID-19 in patients with allergic rhinitis, whereas the effect of inhaled corticosteroids is confounded by asthma severity. These observations reinforce the importance of keeping allergic diseases under control during pandemics. The use of biologicals during COVID-19 is generally regarded as safe, but more evidence is needed. The pandemic substantially changed the management of allergic disorders such as home implementation of various biologicals, allergen immunotherapy, food introduction, and increased use of telemedicine and even home management of anaphylaxis to reduce emergency department burden and reduce risk of infection. Physicians need to be aware of the potential impact of COVID-19 on allergic diseases and educate their patients on the importance of continuing prescribed medications and adhering to their treatment plans to maintain optimal control of their disease.

Differences in Mortality Among Patients With Asthma and COPD Hospitalized With COVID-19

BACKGROUND

It remains unclear whether patients with asthma and/or chronic obstructive pulmonary disease (COPD) are at increased risk for severe coronavirus disease 2019 (COVID-19).

OBJECTIVE

Compare in-hospital COVID-19 outcomes among patients with asthma, COPD, and no airway disease.

METHODS

A retrospective cohort study was conducted on 8,395 patients admitted with COVID-19 between March 2020 and April 2021. Airway disease diagnoses were defined using International Classification of Diseases, 10th Revision codes. Mortality and sequential organ failure assessment (SOFA) scores were compared among groups. Logistic regression analysis was used to identify and adjust for confounding clinical features associated with mortality.

RESULTS

The median SOFA score in patients without airway disease was 0.32 and mortality was 11%. In comparison, asthma patients had lower SOFA scores (median 0.15; P < .01) and decreased mortality, even after adjusting for age, diabetes, and other confounders (odds ratio 0.65; P = .01). Patients with COPD had higher SOFA scores (median 0.86; P < .01) and increased adjusted odds of mortality (odds ratio 1.40; P < .01). Blood eosinophil count of 200 cells/μL or greater, a marker of type 2 inflammation, was associated with lower mortality across all groups. Importantly, patients with asthma showed improved outcomes even after adjusting for eosinophilia, indicating that noneosinophilic asthma was associated with protection as well.

CONCLUSIONS

COVID-19 severity was increased in patients with COPD and decreased in those with asthma, eosinophilia, and noneosinophilic asthma, independent of clinical confounders. These findings suggest that COVID-19 severity may be influenced by intrinsic immunological factors in patients with airway diseases, such as type 2 inflammation.

The Impact of SARS-CoV-2 Infection on Symptom Control and Lung Function in Children with Asthma

Rationale: Little is known about the long-term impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on children with asthma. Objectives: To determine whether SARS-CoV-2 infection affects symptom control and lung function in children with asthma. Methods: Using data from clinical registries and the electronic health record, we conducted a prospective case-control study of children with asthma aged 6-21 years who had (cases) or did not have (control subjects) SARS-CoV-2 infection, comparing baseline and follow-up asthma symptom control and spirometry within an ∼18-month time frame and, for cases, within 18 months of acute coronavirus disease (COVID-19). Results: A total of 171 cases had baseline and follow-up asthma symptom data, and 114 cases had baseline and follow-up spirometry measurements. There were no significant differences in asthma symptom control (P = 0.50), forced expiratory volume in 1 second (P = 0.47), forced vital capacity (P = 0.43), forced expiratory volume in 1 second/forced vital capacity (P = 0.43), or forced expiratory flow, midexpiratory phase (P = 0.62), after SARS-CoV-2 infection. Compared with control subjects (113 with symptom data and 237 with spirometry data), there were no significant differences in follow-up asthma symptom control or lung function. A similar proportion of cases and control subjects had poorer asthma symptom control (17.5% vs. 9.7%; P = 0.07) or worse lung function (29.0% vs. 32.5%; P = 0.50) at follow-up. Patients whose asthma control worsened after COVID-19 had a shorter time to follow-up (3.5 [1.5-7.5] vs. 6.1 [3.1-9.8] mo; P = 0.007) and were more likely to have presented with an asthma exacerbation during COVID-19 (46% vs. 26%; P = 0.04) than those without worse control. Conclusions: We found no significant differences in asthma symptom control or lung function in youth with asthma up to 18 months after acute COVID-19, suggesting that COVID-19 does not affect long-term asthma severity or control in the pediatric population.

Asthma in the era of COVID-19

Since its global invasion in 2019, COVID-19 has affected several aspects of patients' lives and posed a significant impact on the health care system. Several patient populations were identified to be at high risk of contracting SARS-CoV-2 infection and/or developing severe COVID-19-related sequelae. Conversely, anyone who has contracted SARS-CoV-2 is at risk to experience symptoms and signs consistent with post-COVID manifestations. Patients with asthma were initially thought to be at increased risk and severity for SARS-CoV-2 infection. However, accumulating evidence demonstrates that asthma endotypes/phenotypes and comorbidities influence the risk stratification in this population. Furthermore, initial concerns about the potentially increased risk of poor outcomes with asthma treatments such as inhaled corticosteroids and biologics have not been substantiated. In this review, we provide an update on COVID-19 and asthma, including risk of susceptibility, clinical manifestations and course in this population as well as discuss recommendations for management.

Intranasal steroid use and COVID-19 mortality among patients with asthma and COPD: A retrospective cohort study

BACKGROUND

Systemic corticosteroids have been widely used for treating patients with severe acute respiratory distress syndrome. Inhaled corticosteroids may have a protective effect for treating acute coronavirus disease 2019 (COVID-19); however, little is known about the potential effect of intranasal corticosteroids (INCS) on COVID-19 outcomes and severity.

OBJECTIVE

To assess the impact of prior long-term INCS exposure on COVID-19 mortality among patients with chronic respiratory disease and in the general population.

METHODS

A retrospective cohort study was conducted. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between INCS exposure and all-cause and COVID-19 mortality, adjusted by age, sex, deprivation, exacerbations in the last year, and comorbidities.

RESULTS

Exposure to INCS did not have a significant association with COVID-19 mortality among the general population or cohorts with chronic obstructive pulmonary disease or asthma, with HRs of 0.8 (95% CI, 0.6-1.0, P = .06), 0.6 (95% CI, 0.3-1.1, P = .1), and 0.9 (95% CI, 0.2-3.9, P = .9), respectively. Exposure to INCS was, however, significantly associated with reduction in all-cause mortality in all groups, which was 40% lower (HR, 0.6 [95% CI, 0.5-0.6, P < .001]) among the general population, 30% lower (HR, 0.7; 95% CI, 0.6-0.8, P < .001) among patients with chronic obstructive pulmonary disease, and 50% lower (HR, 0.5; 95% CI, 0.3-0.7, P = .003) among patients with asthma.

CONCLUSION

The role of INCS in COVID-19 is still unclear, but exposure to INCS does not adversely affect COVID-19 mortality. Further studies are needed to explore the association between their use and inflammatory activation, viral load, angiotensin-converting enzyme 2 gene expression, and outcomes, exploring different types and doses of INCS.

Viral infections and chronic rhinosinusitis

Viral infections are the most common cause of upper respiratory infections; they frequently infect adults once or twice and children 6 to 8 times annually. In most cases, these infections are self-limiting and resolve. However, many patients with chronic rhinosinusitis (CRS) relay that their initiating event began with an upper respiratory infection that progressed in both symptom severity and duration. Viruses bind to sinonasal epithelia through specific receptors, thereby entering cells and replicating within them. Viral infections stimulate interferon-mediated innate immune responses. Recent studies suggest that viral infections may also induce type 2 immune responses and stimulate the aberrant production of cytokines that can result in loss of barrier function, which is a hallmark in CRS. The main purpose of this review will be to highlight common viruses and their associated binding receptors and highlight pathophysiologic mechanisms associated with alterations in mucociliary clearance, epithelial barrier function, and dysfunctional immune responses that might lead to a further understanding of the pathogenesis of CRS.

Altered renin-angiotensin system gene expression in airways of antigen-challenged mice: ACE2 downregulation and unexpected increase in angiotensin 1-7

OBJECTIVE

Evidence suggest that the renin-angiotensin system (RAS) is activated in people with asthma, although its pathophysiological role is unclear. Angiotensin-converting enzyme 2 (ACE2) is the major enzyme that converts angiotensin II to angiotensin 1-7 (Ang-1-7), and is also known as a receptor of SARS-CoV-2. The current study was conducted to identify the change in RAS-related gene expression in airways of a murine asthma model.

METHODS

The ovalbumin (OA)-sensitized mice were repeatedly challenged with aerosolized OA to induce asthmatic reaction. Twenty-four hours after the last antigen challenge, the main bronchial smooth muscle (BSM) tissues were isolated.

RESULTS

The KEGG pathway analysis of differentially expressed genes in our published microarray data revealed a significant change in the RAS pathway in the antigen-challenged mice. Quantitative RT-PCR analyses showed significant increases in the angiotensin II-generating enzymes (Klk1, Klk1b3 and Klk1b8) and a significant decrease in Ace2. Surprisingly, ELISA analyses revealed a significant increase in Ang-1-7 levels in bronchoalveolar lavage (BAL) fluids of the antigen-challenged animals, while no significant change in angiotensin II was observed. Application of Ang-1-7 to the isolated BSMs had no effect on their isometrical tension.

CONCLUSION

The expression of Ace2 was downregulated in the BSMs of OA-challenged mice, while Klk1, Klk1b3 and Klk1b8 were upregulated. Despite the downregulation of ACE2, the level of its enzymatic product, Ang-1-7, was increased in the inflamed airways, suggesting the existence of an unknown ACE2-independent pathway for Ang-1-7 production. The functional role of Ang-1-7 in the airways remains unclear.

Short- and long-term outcomes of patients with hyper or hypothyroidism following COVID vaccine

Since the beginning of the wide-scale anti-Coronavirus disease 2019 (COVID-19) vaccination program, sporadic cases of thyroid disease following vaccination have been reported. We describe 19 consecutive cases of COVID vaccine-related thyroid disease. Medical records were reviewed for 9 patients with Graves' disease (GD) and 10 with Thyroiditis, all of whom were diagnosed following COVID-19 vaccination. In the GD group, the median age was 45.5 years, female/male(F/M) ratio 5:4, thyroid-stimulating immunoglobulins were elevated in seven patients. The median time from vaccination to diagnosis was 3 months. Methimazole treatment was given to all but one patient. At a median follow-up of 8.5 months from vaccination, three patients were still on methimazole, five went into remission (data were missing for one). In the Thyroiditis group, the median age was 47 years, the F/M ratio 7:3. Thyroiditis was diagnosed after the first, second, and third doses in one, two, and seven patients, respectively. The median time from vaccination to diagnosis was 2 months. TPO antibodies were positive in three patients. All patients were euthyroid off medication at the last visit. Six patients were diagnosed in the hypothyroid phase at 2.5 months from vaccination. Four resolved spontaneously at 3, 6, 4, and 8 months; the other two were treated with thyroxine at 1.5 and 2 months from vaccination and remained on treatment at their last visit, at 11.5 and 8.5 months, respectively. Thyroid disease should be included among possible complications of COVID-19 vaccine and either a late onset or delayed diagnosis should be considered.

Asthma and COVID-19: a controversial relationship

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection induces a spectrum of clinical manifestations that depend on the immune response of the patient, i.e., from an asymptomatic form to an inflammatory response with multiorgan deterioration. In some cases, severe cases of SARS-CoV-2 are characterized by an excessive, persistent release of inflammatory mediators known as a cytokine storm. This phenomenon arises from an ineffective T helper (Th)-1 response, which is unable to control the infection and leads to a reinforcement of innate immunity, causing tissue damage. The evolution of the disease produced by SARS-CoV2, known as COVID-19, has been of interest in several research fields. Asthma patients have been reported to present highly variable outcomes due to the heterogeneity of the disease. For example, the Th2 response in patients with allergic asthma is capable of decreasing Th1 activation in COVID-19, preventing the onset of a cytokine storm; additionally, IL-33 released by damaged epithelium in the context of COVID-19 potentiates either Th1 or T2-high responses, a process that contributes to poor outcomes. IL-13, a T2-high inflammatory cytokine, decreases the expression of angiotensin converting enzyme-2 (ACE2) receptor, hindering SARS-CoV-2 entry; finally, poor outcomes have been observed in COVID-19 patients with severe neutrophilic asthma. In other contexts, the COVID-19 lockdown has had interesting effects on asthma epidemiology. The incidence of asthma in the most populated states in Mexico, including Tamaulipas, which has the highest asthma incidence in the country, showed similar tendencies independent of how strict the lockdown measures were in each state. As described worldwide for various diseases, a decrease in asthma cases was observed during the COVID-19 lockdown. This decrease was associated with a drop in acute respiratory infection cases. The drop in cases of various diseases, such as diabetes, hypertension or depression, observed in 2020 was restored in 2022, but not for asthma and acute respiratory infections. There were slight increases in asthma cases when in-person classes resumed. In conclusion, although many factors were involved in asthma outcomes during the pandemic, it seems that acute respiratory infection is intimately linked to asthma cases. Social distancing during remote learning, particularly school lockdown, appears to be an important cause of the decrease in cases.

Endothelial Glycocalyx Injury in SARS-CoV-2 Infection: Molecular Mechanisms and Potential Targeted Therapy

This review aims at summarizing state-of-the-art knowledge on glycocalyx and SARS-CoV-2. The endothelial glycocalyx is a dynamic grid overlying the surface of the endothelial cell (EC) lumen and consists of membrane-bound proteoglycans and glycoproteins. The role of glycocalyx has been determined in the regulation of EC permeability, adhesion, and coagulation. SARS-CoV-2 is an enveloped, single-stranded RNA virus belonging to β-coronavirus that causes the outbreak and the pandemic of COVID-19. Through the respiratory tract, SARS-CoV-2 enters blood circulation and interacts with ECs possessing angiotensin-converting enzyme 2 (ACE2). Intact glycolyx prevents SARS-CoV-2 invasion of ECs. When the glycocalyx is incomplete, virus spike protein of SARS-CoV-2 binds with ACE2 and enters ECs for replication. In addition, cytokine storm targets glycocalyx, leading to subsequent coagulation disorder. Therefore, it is intriguing to develop a novel treatment for SARS-CoV-2 infection through the maintenance of the integrity of glycocalyx. This review aims to summarize state-of-the-art knowledge of glycocalyx and its potential function in SARS-CoV-2 infection.

Advances in the Relationship between Respiratory Viruses and Asthma

Several studies have reported that viral infection is closely associated with the onset, progression, and exacerbation of asthma. The purpose of this review is to summarize the role that viral infections have in the pathogenesis of asthma onset and exacerbations, as well as discuss interrelated protective and risk factors of asthma and current treatment options. Furthermore, we present current knowledge of the innate immunological pathways driving host defense, including changes in the epithelial barrier. In addition, we highlight the importance of the genetics and epigenetics of asthma and virus susceptibility. Moreover, the involvement of virus etiology from bronchiolitis and childhood wheezing to asthma is described. The characterization and mechanisms of action of the respiratory viruses most frequently related to asthma are mentioned.

Immunologic and Autoimmune-Related Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 Infection: Clinical Symptoms and Mechanisms of Disease

The COVID-19 pandemic has resulted in a significant number of people developing long-term health effects of postacute sequelae SARS-CoV-2 infection (PASC). Both acute COVID-19 and PASC are now recognized as multiorgan diseases with multiple symptoms and disease causes. The development of immune dysregulation during acute COVID-19 and PASC is of high epidemiologic concern. Both conditions may also be influenced by comorbid conditions such as pulmonary dysfunction, cardiovascular disease, neuropsychiatric conditions, prior autoimmune conditions and cancer. This review discusses the clinical symptoms, pathophysiology, and risk factors that affect both acute COVID-19 and PASC.

Longitudinal Analysis of Pulmonary Function Impairment One Year Post-COVID-19: A Single-Center Study

Persistent pulmonary impairment post-COVID-19 has been reported, albeit variably. This single-center observational study aims to longitudinally evaluate pulmonary function in 140 COVID-19 survivors one year after recovery, assessing associations with disease severity and pre-existing lung conditions. Participants aged 18 and older, with confirmed SARS-CoV-2 infection, were evaluated using spirometry and Diffusion Capacity of Lungs for Carbon Monoxide (DLCO) tests. Pulmonary function parameters like Forced Expiratory Volume at 1 s (FEV1), Forced Vital Capacity (FVC), and Total Lung Capacity (TLC) were measured. Participants were stratified by age, gender, body mass index, smoking status, and lung damage severity via computed tomography (CT). The cohort consisted of mostly males (58.6%), with a mean age of 53.8 years and body mass index of 24.9 kg/m2. Post-COVID fibrosis was seen in 22.7%, 27.3%, and 51.9% of mild, moderate, and severe disease patients, respectively (p = 0.003). FVC significantly reduced with disease severity (p < 0.001), while FEV1, FEF25-75, and DLCO showed a non-significant downward trend. FEV1/FVC ratio increased with disease severity (p = 0.033), and TLC and RV significantly declined (p = 0.023 and p = 0.003, respectively). A one-year follow-up indicated a non-significant change in FVC, FEV1, FEV1/FVC ratio, FEF25-75, and RV compared with the 40-day measurement, but it revealed significant improvements in DLCO and TLC (p = 0.010). There were significant mean increases in FVC, FEV1, DLCO, TLC, and RV across all disease severities over one year. They were most pronounced in the patients with a history of severe COVID-19, who had a better recovery over one year, compared with the mild and moderate COVID-19 patients whose lung function almost normalized. One year after the SARS-CoV-2 infection, we observed a significant association between disease severity and post-COVID fibrotic changes. Though some lung function parameters remained stable over the year, significant improvements were noted in DLCO and TLC. Particularly, individuals with severe disease showed substantial recovery in lung function, indicating the potential reversibility of COVID-19-related pulmonary damage.

Oropharyngeal Microbiota Clusters in Children with Asthma or Wheeze Associate with Allergy, Blood Transcriptomic Immune Pathways, and Exacerbation Risk

Rationale: Children with preschool wheezing or school-age asthma are reported to have airway microbial imbalances. Objectives: To identify clusters in children with asthma or wheezing using oropharyngeal microbiota profiles. Methods: Oropharyngeal swabs from the U-BIOPRED (Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes) pediatric asthma or wheezing cohort were characterized using 16S ribosomal RNA gene sequencing, and unsupervised hierarchical clustering was performed on the Bray-Curtis β-diversity. Enrichment scores of the Molecular Signatures Database hallmark gene sets were computed from the blood transcriptome using gene set variation analysis. Children with severe asthma or severe wheezing were followed up for 12-18 months, with assessment of the frequency of exacerbations. Measurements and Main Results: Oropharyngeal samples from 241 children (age range, 1-17 years; 40% female) revealed four taxa-driven clusters dominated by Streptococcus, Veillonella, Rothia, and Haemophilus. The clusters showed significant differences in atopic dermatitis, grass pollen sensitization, FEV1% predicted after salbutamol, and annual asthma exacerbation frequency during follow-up. The Veillonella cluster was the most allergic and included the highest percentage of children with two or more exacerbations per year during follow-up. The oropharyngeal clusters were different in the enrichment scores of TGF-β (transforming growth factor-β) (highest in the Veillonella cluster) and Wnt/β-catenin signaling (highest in the Haemophilus cluster) transcriptomic pathways in blood (all q values <0.05). Conclusions: Analysis of the oropharyngeal microbiota of children with asthma or wheezing identified four clusters with distinct clinical characteristics (phenotypes) that associate with risk for exacerbation and transcriptomic pathways involved in airway remodeling. This suggests that further exploration of the oropharyngeal microbiota may lead to novel pathophysiologic insights and potentially new treatment approaches.

Covid-19 pandemic and asthma: What did we learn?

This review addresses some of the major lessons we have learnt regarding asthma and the covid-19 pandemic, including susceptibility to SARS-CoV-2 infection and severe covid-19, potentially protective factors, comparison to other respiratory infections, changes in healthcare behaviour from the perspective of patients and clinicians, medications to treat or prevent covid-19, and post-covid syndrome.