Background/Objectives: Radon exposure has recently been associated with asthma morbidity, including increased airway inflammation and school absenteeism in children, though limited data on underlying biological mechanisms exist. Interleukin-6 (IL-6), a pleiotropic cytokine implicated in both Type 2-low airway inflammation and radon-related lung carcinogenesis, may represent a key mechanistic link between radon exposure and asthma morbidity. We aimed to evaluate the association between indoor radon exposure and plasma IL-6 levels in children with asthma and whether this relationship differs by allergic sensitization status. Methods: We analyzed baseline data from the School Inner-City Asthma Study, a prospective cohort of children aged 4-13 years with persistent asthma. Monthly indoor radon concentrations at each participant's residential ZIP Code Tabulation Area were estimated using a validated spatiotemporal prediction model. Plasma IL-6 was measured from baseline blood samples. Multivariable linear mixed-effects models with random intercepts for school were used to assess the association between radon exposure and IL-6, adjusting for demographic, clinical, and socioeconomic covariates. Effect modification by allergic sensitization was evaluated using an interaction term. Results: Among 144 participants, 62.5% were allergen-sensitized. The median home radon concentration was 46.6 Bq/m3 (range 30.7-99.9), and the mean plasma IL-6 was 0.22 pg/mL (SD 0.41). A significant interaction was observed between radon exposure and allergic sensitization status (β-interaction = -0.012; p = 0.014), indicating differential effects by phenotype. Among non-sensitized children, higher radon exposure was associated with increased IL-6 levels (β = 0.0088; p = 0.044), corresponding to a 0.32 pg/mL rise in IL-6 per 37 Bq/m3 increase in radon. No significant association was observed among sensitized children. Conclusions: Indoor radon exposure is associated with higher plasma IL-6 levels in non-sensitized children with asthma, suggesting a potential IL-6-mediated pathway linking radon exposure to asthma morbidity in the Type 2-low phenotype. These findings highlight heterogeneity in environmental asthma responses and support further investigation into radon mitigation as a modifiable factor to improve asthma outcomes. IL-6 may serve as a biomarker to identify children most susceptible to radon-related airway inflammation, guiding personalized mitigation strategies and targeted interventions to improve asthma outcomes. Future studies should incorporate direct home radon measurements, comprehensive endotyping panels, and longitudinal biomarker sampling to validate these findings and elucidate whether IL-6 trans-signaling pathways mediate radon-induced airway injury in non-allergic asthma.

Abstract Virus exposure history, particularly first exposure, is believed to shape vaccine efficacy and infection susceptibility; however, evidence for mechanistic links between immune responses in individuals and epidemiological outcome in populations is scarce. Recent co-circulation of SARS-CoV-2 variants XFG and BA.3.2 has revealed a striking enrichment in BA.3.2 cases among children. By combining epidemiological modeling, serology and monoclonal antibody analysis in children and adults, we show the dependence of effective variant-specific antibodies on vaccination history which may explain birth-year influence on differential susceptibility to these co-circulating variants. Ancestral cross-reactive site I antibodies frequently neutralize BA.3.2, but not XFG. By contrast, Omicron type-specific site I/III and III antibodies frequently neutralize XFG but not BA.3.2, revealing a tradeoff in the ability to neutralize these two co-circulating strains. These findings mechanistically link immune history, variant neutralization, antibody repertoire and variant infection risk, and suggest that vaccination regimens in children should prioritize neutralization breadth.

BACKGROUND:The Pandemic Response Repository through Microbial and Immune Surveillance and Epidemiology (PREMISE) programme was established to translate knowledge gained from global immunoepidemiological surveillance into a better understanding of population-level dynamics of emerging and re-emerging infections, as well as into the discovery and development of biomedical countermeasures against potential pandemic threats. As proof of principle for this approach, we conducted a longitudinal immunoepidemiological study in children in the USA, focusing on enterovirus D68 (EV-D68) infection dynamics but also capturing surveillance of a broad array of other endemic respiratory pathogens. Serendipitously, our sampling spanned the lifting of widespread COVID-19 non-pharmaceutical interventions (NPIs) in 2022-23, following a unique period during which virus exposure markedly diminished. METHODS:This prospective, multicentre, longitudinal, immunoepidemiological surveillance study enrolled children aged 10 years or younger and weighing at least 8 kg at three US university sites. Blood specimens collected from January to June, 2022 (visit 1; pre-enterovirus season), and from January to June, 2023 (visit 3; post-enterovirus season), were tested in a multiplex assay for antibody binding to EV-D68 (prespecified primary objective) and a panel of 15 other respiratory viruses (exploratory objectives), and for neutralising activity against EV-D68, enterovirus A71, and respiratory syncytial virus (RSV; for antibody binding assay validation). Respiratory mid-turbinate swabs collected from children with symptomatic illness who participated in symptom surveys during July-December, 2022 (visit 2; enterovirus season), underwent metagenomic sequencing for pathogen detection. Serological data for EV-D68 were incorporated into epidemiological models based on case data from national surveillance to predict future transmission dynamics. FINDINGS:Of 488 eligible children approached, 174, with a median age of 3·4 years (IQR 1·9-6·4), were enrolled and followed up longitudinally from January, 2022, to June, 2023. Three children withdrew before study completion and 51 were lost to follow-up between visits 1 and 3. 90 paired serological samples and 73 respiratory swabs were tested. Mean antibody binding and neutralisation titres against all viruses tested increased over the study period, most notably in younger children with lower initial titres. The highest exposure rates (seroconversion or antibody boosting) were seen with SARS-CoV-2 (51 [59%] of 87), EV-D68 (36 [41%] of 87), RSV (36 [41%] of 87), and influenza (35 [40%] of 87), whereas the pathogens most frequently detected by respiratory swab sequencing were EV-D68 (clade B3), rhinovirus A, and rhinovirus C (n=7 each). Incorporating EV-D68 serological data into epidemiological models resulted in an 82% reduction in the range of prediction errors and a 33% reduction in median prediction errors for longer-term EV-D68 circulation dynamics compared with national pathogen surveillance data alone. INTERPRETATION:In this study, we captured immunological evidence of endemic virus re-emergence in children following lifting of pandemic NPIs, which revealed high rates of exposure to endemic respiratory pathogens in a large group of seronegative, predominantly younger, children. This study demonstrates the feasibility and utility of immunoepidemiological surveillance to enable more precise and accurate modelling of pathogen circulation dynamics to predict and prepare for future waves of disease. FUNDING:Intramural Research Program of the National Institute of Allergy and Infectious Diseases-Vaccine Research Center, and the National Cancer Institute, National Institutes of Health.

Background: Radon is an omnipresent radioactive gas recently reported to be associated with increased asthma morbidity. Objectives: We aimed to identify biomarkers associated with radon exposure and hypothesized elevated radon exposure to be associated with increased inflammatory biomarker levels in an exploratory analysis. Methods: In 137 schoolchildren with asthma in the School Inner-City Asthma Study, we assessed estimated radon exposure (1-month averaged radon) by a spatiotemporal model and 46 inflammatory biomarker outcomes, adjusting for copollutants (particulate matter with diameter <_2.5 m, NO2, O3) and performed mixed-effect regression analysis. Causal mediation analysis was used to determine the association between radon exposure and absolute eosinophil count. Results: In a total of 137 observations, we found a positive association with radon exposure and IL-5, a TH2-cell cytokine known to recruit eosinophils to asthmatic airways. Higher radon was significantly associated with a greater increase in IL5 compared to low radon exposure (observations = 137; 1month moving radon average [% change = 13.4%; 95% CI: 0.4%-28.0%; P = .044]). Mediation analysis revealed an indirect effect of IL-5 ((3 = 0.006; 95% CI:0.001-0.012; P = .024) on the association between radon exposure and absolute eosinophil count. This suggests the effect of radon on eosinophil count is mediated through IL-5. Conclusions: Radon is a potential novel, modifiable risk factor for asthma recently reported to be associated with asthma morbidity. This work identifies important biological disease pathways via biomarkers that may be central to the exposure72.)

Background: The cost-effectiveness of school environmental remediation in asthma is not known. The School Inner City Asthma Intervention Study (SICAS2) was a randomized controlled trial that assessed school integrated pest management (IPM) and classroom high efficiency particulate air (HEPA) filtration on asthma morbidity in urban schools. Objective: The objective was to evaluate the cost-effectiveness of SICAS2. Methods: We conducted a cost-effectiveness analysis from a societal perspective that compared four interventions: IPM, HEPA, IPM + HEPA, and no intervention. Quality-adjusted life years (QALY) were derived from the EuroQol-5 Dimension-Youth and EuroQol-5 Dimension-3 levels instruments. Total costs (2021 U.S. dollars) included intervention cost, cost of caregiver productivity impacted by child school absenteeism, and health-care utilization costs (e.g., emergency department visits). The evaluation period was based on a mean follow-up time of 166 days. Sensitivity analyses were performed by using cost estimates 50% above and below initial cost benchmarks. Results: A total of 154 SICAS2 participants were included. Intervention costs per student were $12.21 (IPM + HEPA), $7.27 (IPM), and $4.94 (HEPA). Sequential analyses revealed that IPM + HEPA was the most cost-effective option, with an incremental cost-effectiveness ratio of $19,667 per QALY. Sensitivity analyses demonstrated stability, with variability in probability estimates not exceeding 10%. Conclusion: IPM + HEPA demonstrated good value to society, which reflected the low cost and the economic impact of missed school days. This intervention may have a pronounced benefit for historically minoritized and marginalized children in urban schools who are disproportionately exposed to air pollution and indoor allergens. The SICAS2 intervention may offer a cost-effective tool to target proximal causes of disparities even in the most resource-limited schools.

Recruitment and retention are challenges for prospective pediatric cohort studies, particularly those involving serial venipunctures. We investigated factors underlying enrollment and retention in the Pandemic Response Repository through Microbial and Immune Surveillance and Epidemiology (PREMISE) Enterovirus D68 (EV-D68) Pilot Study, a multicenter prospective longitudinal cohort study assessing the utility of immunologic surveillance for pandemic preparedness. This study enrolls children ≤10 years for two blood draws, pre- and post-EV-D68 season, separated by 6-18 months. Overall, 174 children were enrolled in Cohort 1 of the study and 120 (69%) of children completed the study, with follow-up blood samples obtained from 101 (58%) of participants. Families were primarily motivated to participate by a desire to help other children, advance science, and better prepare for the next pandemic. Adding research blood draws to clinically indicated blood draws improved enrollment, and multiple study touch points facilitated retention. These findings can be applied to improve recruitment and retention in future pandemic preparedness efforts and longitudinal pediatric cohort studies.

Background: Few data on the relationships between environmental exposures, asthma morbidity, and systemic IL-6 inflammation exist.Objective: We sought to determine whether baseline plasma IL-6 level is associated with increased asthma morbidity in children exposed to mouse allergen in inner-city classrooms.Methods: Data from the longitudinal School Inner-City Asthma Studies of 215 children with asthma, aged 4 to 14 years and recruited from urban elementary schools, were analyzed. Given the unknown threshold of IL-6 risk levels and skewness of the distribution, the children were stratified into tertiles as follows: low baseline IL-6 level (<0.013 pg/mL), moderate baseline IL-6 level (0.013-0.302 pg/mL), and high baseline IL-6 level (>0.302 pg/mL). Relationships between plasma IL-6 level and body mass index (BMI) percentile, inflammatory markers, lung function, mouse allergen exposure, and asthma outcomes were assessed.Results: Cross-sectional analysis demonstrated that increasing IL-6 level was associated with higher BMI percentile (P < .0001), C-reactive protein level (P = .0006), and blood neutrophil count (P = .0024). IL-6 was not associated with type 2 inflammatory markers, including blood eosinophil count, allergic sensitization, or fractional exhaled nitric oxide level. Longitudinal analysis showed that children with high IL-6 levels had a higher number of days with asthma symptoms than did those children with moderate (incidence rate ratio = 1.74 [95% CI = 1.10-2.77]; P = .0187) or low (incidence rate ratio =1.83 [95% CI = 1.21-2.77]; P = .0043) IL-6 levels. Children with high IL-6 levels who were exposed to increasing levels of mouse allergen exhibited lower ratios of FEV1 value to forced vital capacity than did children with moderate IL-6 levels (beta = -0.0044 [95% CI = -0.0073 to -0.0015]; pairwise interaction P = .0028) or low IL-6 levels (beta = -0.0042 [95% CI = - 0.0070 to -0.0013]; pairwise interaction P = .0039).Conclusions: Inner-city children with asthma and high plasma IL-6 levels are more likely to have an increased BMI, elevated C-reactive protein level, elevated blood neutrophil count, and greater asthma symptoms. High IL-6 level appears to increase susceptibility to the effects of classroom exposure to mouse allergen on lung function in urban children.

Objective The School Inner-City Asthma Intervention Study 2 (SICAS 2) tested interventions to reduce exposures in classrooms of students with asthma. The objective of this post-hoc analysis was limited to evaluating the effect of high-efficiency particulate (HEPA) filtration interventions on mold levels as quantified using the Environmental Relative Moldiness Index (ERMI) and the possible improvement in the students' asthma, as quantified by spirometry testing. Methods Pre-intervention dust samples were collected at the beginning of the school year from classrooms and corresponding homes of students with asthma (n = 150). Follow-up dust samples were collected in the classrooms at the end of the HEPA or Sham intervention. For each dust sample, ERMI values and the Group 1 and Group 2 mold levels (components of the ERMI metric) were quantified. In addition, each student's lung function was evaluated by spirometry testing, specifically the percentage predicted forced expiratory volume at 1 sec (FEV1%), before and at the end of the intervention. Results For those students with a higher Group 1 mold level in their pre-intervention classroom than home (n = 94), the FEV1% results for those students was significantly (p < 0.05) inversely correlated with the Group 1 level in their classrooms. After the HEPA intervention, the average Group 1 and ERMI values were significantly lowered, and the average FEV1% test results significantly increased by an average of 4.22% for students in HEPA compared to Sham classrooms. Conclusions HEPA intervention in classrooms reduced Group 1 and ERMI values, which corresponded to improvements in the students' FEV1% test results.

Plasma cotinine (nicotine metabolite) levels correlate with smoke exposure. Primary and secondary smoke exposure increase cotinine levels and asthma exacerbations. We hypothesized that asthma severity is positively correlated with smoke exposure as determined by detectable plasma cotinine levels. The NewYork-Presbyterian (NYP) Pediatric Asthma Cohort Study enrolled patients, ages 2-20 years with and without asthma, from outpatient clinics. A physician diagnosis of asthma was used to identify asthma versus control. Plasma cotinine levels were assessed, and a survey completed. 190 predominantly Black (29%) or Hispanic (56%) patients were included in analyses, 112 asthma and 78 control. Cotinine was detected in 26 (14%) of patients. Of patients who had detectable levels, 71% had household incomes <$45,000 and 29% >$45,000 while of those with undetectable levels, 42% had incomes <$45,000 and 58% >$45,000(p=0.012). Patients with detectable levels had a higher median age (16 vs. 14 years; p=0.037). Cotinine levels were detected in 10% of participants who were never/rarely exposed, 0% exposed several times a month, and 35% exposed several times a week/daily(p=0.013). Cotinine levels were detected in 57% of patients with primary and secondary smoke exposure, 0% with primary, 23% with secondary, and 10% with no exposure (p=0.006). Cotinine levels were detected in 14% of control patients, 10% with intermittent/mild persistent asthma, 19% with moderate/severe persistent asthma(p=0.4). Differences in cotinine detection were seen based on household income, age, and the type and frequency of smoke exposure. Although detectable cotinine levels were highest in patients with severe asthma, it did not reach statistical significance.

In the autumn of 2014, the USA faced an unexpected spike in cases of previously healthy children stricken with polio-like paralysis following a febrile respiratory illness. Since that time, research efforts have shed light on the causes, mechanisms, and outcomes of this disease, now termed acute flaccid myelitis.1Murphy OC Messacar K Benson L et al.Acute flaccid myelitis: cause, diagnosis, and management.Lancet. 2021; 397: 334-346Summary Full Text Full Text PDF PubMed Scopus (16) Google Scholar However, subsequent seasonal outbreaks have continued, in North America and Europe in 2016 and 2018, and have been increasingly recognised around the globe. To date, there remain no known effective treatments or prevention strategies for acute flaccid myelitis, which has left over 650 children in the USA profoundly affected, most with permanent paralysis. Following the absence of a predicted spike in cases in 2020, most likely due to non-pharmaceutical interventions in response to the COVID-19 pandemic, the next acute flaccid myelitis outbreak is looming, but timing remains unknown. Epidemiological, clinical, and laboratory data indicate that non-polio enteroviruses, most notably enterovirus D68, are the predominant drivers behind the recent increase in acute flaccid myelitis cases.2Messacar K Asturias EJ Hixon AM et al.Enterovirus D68 and acute flaccid myelitis—evaluating the evidence for causality.Lancet Infect Dis. 2018; 18: e239-e247Summary Full Text Full Text PDF PubMed Scopus (108) Google Scholar Enterovirus D68 is an emerging RNA virus spread via respiratory transmission, causing outbreaks of severe respiratory symptoms including wheezing and respiratory distress. Laboratory models suggest that enterovirus D68 can infect neurons and spread via retrograde axonal transport in vitro and can lead to spinal cord motor neuron death resulting in acute flaccid myelitis-like paralysis in mice. Monoclonal antibodies and vaccine candidates are in early preclinical stages of development, but there are currently no approved therapies or vaccines against enterovirus D68. The COVID-19 pandemic has underscored the urgency required to meet the threat of unexpected spikes of illnesses due to emerging pathogens. Comprehensive immunological surveillance that rapidly maps reactivity to viral infections of known and unknown causes, and which represent potential epidemic and pandemic threats, is currently inadequate. The implementation and deployment of such global reconnaissance for infectious diseases would enable rapid development of diagnostic and therapeutic agents and vaccines to pre-empt and thus mitigate widespread disease. As non-pharmaceutical interventions for the COVID-19 pandemic are lifted, respiratory viruses, including enterovirus D68, are likely to return with consequentially larger susceptible populations. The challenge presented by enterovirus D68, and the likelihood of an impending resurgence, makes this an ideal test case for the ability of immunological surveillance to rapidly develop tools to mitigate the pandemic potential of an emerging pathogen. Since 2014, outbreaks of enterovirus D68 cases in the USA have geographically and temporally coincided with seasonal biennial spikes in acute flaccid myelitis cases.3Park SW Pons-Salort M Messacar K et al.Epidemiological dynamics of enterovirus D68 in the United States and implications for acute flaccid myelitis.Sci Transl Med. 2021; 13eabd2400Crossref Scopus (14) Google Scholar Understanding the epidemiological dynamics of enterovirus D68 has remained a key question in predicting its future outbreaks and identifying its causal link with acute flaccid myelitis. Biennial epidemic patterns have historically been found in acute immunising infections, hinting at the strength and duration of immunity against natural enterovirus D68 infections. Classical studies of pre-vaccination measles outbreaks in the UK lend insight into core mechanisms driving biennial patterns: large outbreaks deplete the susceptible pool and limit the size of future outbreaks until the susceptible pool is replenished via birth cohorts. Epidemiological analyses of biennial outbreaks of enterovirus D68 and other enteroviruses support this mechanism.3Park SW Pons-Salort M Messacar K et al.Epidemiological dynamics of enterovirus D68 in the United States and implications for acute flaccid myelitis.Sci Transl Med. 2021; 13eabd2400Crossref Scopus (14) Google Scholar, 4Pons-Salort M Grassly NC Serotype-specific immunity explains the incidence of diseases caused by human enteroviruses.Science. 2018; 361: 800-803Crossref PubMed Scopus (59) Google Scholar Because of the ongoing COVID-19 pandemic, non-pharmaceutical interventions such as mask wearing and social distancing most likely prevented the predicted enterovirus D68 outbreak in 2020, but increased the susceptible pool of individuals, creating an immunity gap (appendix pp 1–2). This gap could, in turn, cause a large outbreak after the interventions are lifted (appendix pp 1–2). Although delayed outbreaks are expected to be larger due to additional increases in the susceptible pool, even a modest reduction in transmission rates—either due to partial lifting of COVID-19 interventions (appendix pp 1–2) or seasonality—can reduce the size of the outbreak. For example, a 60% reduction in transmission rate in 2020 results in a delayed, but smaller, outbreak due to decreased transmission of enterovirus D68 during winter. Although the exact timing of the next enterovirus D68 outbreak is difficult to predict, large outbreaks of enterovirus D68, and therefore acute flaccid myelitis, are likely to be imminent. An analogy can be made to the 1950s in the USA when the baby boom increased the susceptible pool and led to a sudden, drastic increase in poliovirus poliomyelitis cases.5Martinez-Bakker M King AA Rohani P Unraveling the transmission ecology of polio.PLoS Biol. 2015; 13e1002172Crossref PubMed Scopus (41) Google Scholar The need to further understand seroprevalence of enterovirus D68 in preparation of the next potential outbreak and the absence of current countermeasures for acute flaccid myelitis, creates an opportunity to use enterovirus D68 as a test case to pilot the development of an immunological surveillance programme to help alleviate future outbreaks of enterovirus D68, with implications for other serious childhood respiratory diseases and emerging human pathogens with pandemic potential. Although some passive, retrospective surveillance exists for enterovirus D68 and acute flaccid myelitis, there is a critical need for real-time immunology-based surveillance systems to provide specialised biological specimens, such as prospectively collected peripheral blood mononuclear cells, serum, and plasma, from children likely to have primary infection with contemporary circulating enterovirus D68 strains and other respiratory diseases. These types of specimens are a key component to rapid development of vaccine candidates, such as the highly successful SARS-CoV-2 vaccines. Enterovirus D68 presents a timely opportunity to pilot an immunological surveillance programme because of the high probability of an impending resurgence of this pathogen of public health significance in need of rapid development of novel therapies and vaccine candidates. The COVID-19 pandemic has demonstrated a critical need to establish a pre-emptive stockpile of tangible immunobiological countermeasures to accelerate the response to potential pandemic threats. To address this need we have established a pandemic response repository through microbial and immunological surveillance and epidemiology (PREMISE) initiative (appendix pp 1–2). While rapid detection and surveillance of novel and emerging pathogens are well-recognised core components of pandemic preparedness, deep analysis of host immune responses at a population-wide scale is a parallel, but currently insufficient, fundamental component of a swift, effective response to infectious threats.6Mina MJ Metcalf CJE McDermott AB Douek DC Farrar J Grenfell BT A global immunological observatory to meet a time of pandemics.Elife. 2020; 9e58989Crossref PubMed Google Scholar PREMISE aims to conduct immune analysis of targeted and broad human cohorts to detect reactivity against potentially pandemic viruses, and to identify immunogens suitable for vaccine discovery and monoclonal antibodies for prevention and therapy using a pathogen-agnostic approach. Deliverables will include sequence information of immunogenic regions and monoclonal antibodies specific for viruses of concern, and resources for early detection and diagnostic assays. Additionally, seroepidemiology data will shed light on the duration of maternal antibody protection, age at primary infection, and dynamics of spread of recently emerging strains to guide pandemic response. PREMISE is not a global serosurveillance network or an early warning system, although its goal is to use information from serosurveillance networks for immunological and virological screening and product design. PREMISE is also not a prototype pathogen approach to vaccine design, which is a virological approach, but aims to use an immunological approach to work synergistically with prototype pathogen approaches to identify immunologically relevant proteins leading to the discovery of immunobiological products. The strengths of PREMISE will be its ability to map the landscape of immunological activity to known and unknown pathogens and to use these findings to discover immunobiologicals to anticipate and accelerate the global response to pandemic threats. Using enterovirus D68 as a test case for PREMISE will provide insight into enterovirus D68 seroepidemiology and establish an immunological biorepository to expedite the ability to respond to future enterovirus D68 acute flaccid myelitis outbreaks, as well as establish best practices for future pandemic pathogen immune surveillance. Preparedness for emerging pathogens, such as enterovirus D68, relies on both pathogen surveillance and immunological surveillance to guide rapid development of diagnostic, therapeutic, and preventative tools to combat the next pandemic. By using PREMISE to combat future outbreaks of enterovirus D68 acute flaccid myelitis, we aim to rapidly develop countermeasures for this devastating disease and from there expand the programme to better prepare for future emerging pathogens with pandemic potential. SRD reports contracts from Biofire Diagnostics and Pfizer; consulting fees from Biofire Diagnostics, DiaSorin Molecular, and Karius, outside the submitted work. MRV reports grants from the US National Institute of Allergy and Infectious Disease, the Thrasher Research Fund, the Pediatric Infectious Diseases Society Foundation; consulting fees from IDBiologics and HDT Bio, outside the submitted work. MRV is also an inventor a pending international patent application on human monoclonal antibodies to enterovirus D68. SP reports contracts from Merck Vaccines and Moderna for institutional sponsored programmes, and consulting fees from Moderna, Merck, Dynavax, Pfizer, and HOOKIPA Biotech, outside the submitted work. All other authors declare no competing interests. HN-T and SWP contributed equally. Download .pdf (.47 MB) Help with pdf files Supplementary appenqdix

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are essential nutrients that can affect inflammatory responses. While n-3 PUFAs are generally considered beneficial for cardiovascular disease and obesity, the effects on asthma, the most common inflammatory lung disease are unclear. While prenatal dietary n-3 PUFAs decrease the risk for childhood wheezing, postnatal dietary n-3 PUFAs can worsen allergic airway inflammation. Sphingolipid metabolism is also affected by dietary n-3 PUFAs. Decreased sphingolipid synthesis leads to airway hyperreactivity, besides inflammation, a cardinal feature of asthma, and common genetic asthma risk alleles lead to lower sphingolipid synthesis. We investigated the effect of dietary n-3 PUFAs on sphingolipid metabolism and airway reactivity. Comparing a fish-oil diet with a high n-3 PUFA content (FO) to an isocaloric coconut oil-enriched diet (CO), we found an n-3 PUFA-dependent effect on increased airway reactivity, that was not accompanied by inflammation. Lung and whole blood content of dihydroceramides, ceramides, sphingomyelins, and glucosylceramides were lower in mice fed the n-3 PUFA enriched diet consistent with lower sphingolipid synthesis. In contrast, phosphorylated long chain bases such as sphingosine 1-phosphate were increased. These findings suggest that dietary n-3 PUFAs affect pulmonary sphingolipid composition to favor innate airway hyperreactivity, independent of inflammation, and point to an important role of n-3 PUFAs in sphingolipid metabolism.

To the Editor, Infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in children rarely leads to severe disease. This has been particularly surprising for children with asthma—the most common, chronic inflammatory disease in childhood. We sought to determine predictors for COVID-19 infection and symptomatic illness in children and adolescents, with and without asthma, at risk for SARS-CoV-2 across the epicenter of the ongoing pandemic in New York City (NYC). Data collected from May 2020 through April 2021 during the early pandemic and before vaccine roll-out as part of the ongoing observational SARS-CoV-2 and Pediatric Asthma in NYC (SPAN) urban cohort study of children and adolescents were analyzed. Study participants were recruited during routine New York-Presbyterian/Weill Cornell Medicine outpatient clinic visits across the epicenter of the COVID-19 pandemic including general pediatrics, adolescent, pulmonary, and allergy clinics. The study population included participants aged 2–21 years without asthma and those with physician-diagnosed asthma for at least 1 year and at least one of the following: current daily preventive asthma medication use, wheezing in the past year, or an unscheduled healthcare visit for asthma in the past year. Parents/legal guardians of enrolled participants gave written informed consent. Written assent was obtained from participants aged 7–17 years. This study was approved by Institutional Review Boards at Weill Cornell Medicine, New York-Presbyterian Queens, and New York-Presbyterian Brooklyn Methodist Hospital. A comprehensive survey administered to the parent/legal guardian included questions regarding demographics, clinical information, and exposures, specifically as it pertained to COVID-19 illness. Body mass index (BMI) was calculated using the weight data (kg) and dividing it by height (m) squared (kg/m2). Pediatric age and sex-adjusted BMI percentiles were then calculated using the Centers for Disease Control classification category: normal weight (5–84th BMI percentile), overweight (≥85–94th BMI percentile), and obese (≥95th BMI percentile). Blood and nasal biospecimens were collected during the participants' outpatient clinic visits. As variations at the asthma-risk 17q21 locus are associated with ORMDL3 and Gasdermin B expression, in particular the minor risk allele (T) of single-nucleotide polymorphism (SNP) rs7216389, and strongly linked to childhood asthma and viral triggers for wheezing,1, 2 genotyping of this SNP was performed on extracted DNA using QIAamp DNA blood micro/mini kits (QIAGEN) according to manufacturer's instructions. The SNP genotyping was performed using the TaqMan® SNP Genotyping Assay (SNP ID: rs7216389). Each SNP genotyping reaction was carried out in duplicate. The SNP genotyping reaction was run in a QuantStudio 6 Flex Real-Time PCR System and the data was analyzed using QuantStudio Software (Applied Biosystems). COVID-19 infection was ascertained by positive SARS-CoV-2 specific antibodies. Immunoglobulin G antibodies against SARS-CoV-2 were determined in plasma by enzyme-linked immunosorbent assay using the SARS-CoV-2 spike protein as antigen as previously described.3 Descriptive statistics were calculated to characterize the SPAN cohort (Table 1). Primary outcomes of interest included: (1) positive COVID-19 serology test and (2) symptomatic COVID-19 illness defined as having a positive COVID-19 test and having at least one of the following symptoms—fever, chills, sore throat, cough, body aches, nasal congestion, rhinorrhea, loss of taste, anosmia, shortness of breath, diarrhea, vomiting, rash, and/or COVID toes, or hospitalization. Univariate logistic regression modeling calculated the unadjusted odds ratio (OR) for each of the demographic and clinical factors of interest on both outcomes, independently. A multivariate logistic regression model evaluated the independent effect of ORMDL genotype on developing COVID-19 while controlling for potential confounders such as age, inhaled corticosteroid (ICS) use, race, borough of residence, household SARS-CoV-2 exposure, and BMI. Borough of residence was included in the multivariable analysis since during the first waves of the COVID-19 pandemic in NYC (when this study was conducted), certain boroughs were particularly affected with higher numbers of infected individuals. For instance, Queens was at the epicenter early on in the pandemic. Moreover, the borough of residence might be linked to other demographic factors such as race, ethnicity, socioeconomic factors, and body mass index. Collinearity between predictors in the models was evaluated before the formulation of the final model. Ninety-five percent confidence intervals for all parameters of interest were calculated to assess the precision of the obtained estimates. All p values were two-sided with statistical significance evaluated at the 0.05 alpha level. All analyses were performed in R Version 4.0.5 (R Foundation for Statistical Computing). Of the 186 participants enrolled, 68 (37%) were infected with SARS-CoV-2, and of these, 38 (56%) endorsed symptoms, and 2 (2.9%) were hospitalized. Sixty-nine participants were obese (37%) while 117 (63%) were nonobese (combined healthy weight and overweight); there was a significantly higher rate of obesity in SARS-CoV-2 infected children (p = 0.006) (Table 1). Children with symptomatic COVID-19 illness were older (p = 0.016) and had a higher rate of influenza vaccination in the recent season (p = 0.020) compared to participants with asymptomatic COVID-19. Multivariable logistic regression analysis showed that obesity (p = 0.049) and household SARS-CoV-2 exposure (p < 0.001) were risk factors for acquiring SARS-CoV-2 infection in all participants (asthma and nonasthma) while the T/T genotype (p = 0.029) was associated with decreased infection risk in asthma participants only. Increasing age (p = 0.029) was the only predictor associated with more symptomatic illness on univariate analysis and trended towards significance with multivariable logistic regression analysis (Table 2). We did not find an association between SNP rs7216389 and asthma status (Supporting Information: Table E1). Additionally, there were no differences in minor allele frequency by race (Supporting Information: Table E2). Since the frequency of C/C genotype is low (10%) compared to T/T (45%) and C/T (45%), consistent with findings from other pediatric cohorts,1 comparisons were made between T/T versus C/T or C/C (Table 2, Supporting Information: Table E3). The primary objective of this analysis was to better understand the demographic and clinical factors associated with COVID-19 infection and symptomatic illness in the pediatric population during the early pandemic before vaccine roll-out, particularly in those with asthma. Most COVID-19 pediatric investigations have been retrospective analyses of hospitalized children; thus, observational cohort studies in nonhospitalized and healthy children are essential to assess prevalence and risk for COVID-19. As such, the SPAN cohort offers unique data and exhibited a high prevalence of SARS-CoV-2 infection in the outpatient setting; almost half were asymptomatic and unaware they had contracted COVID-19. As anticipated, home contact increased the risk for infection. Similar to adult studies, obesity was associated with an increased risk for infection4 but was not associated with symptomatic illness. Impairment of both innate and adaptive immune responses as well as vitamin D deficiency have all been linked to obesity-related susceptibility to acquiring infections.5 A plausible explanation for why obese BMI was not associated with symptomatic COVID-19 in our study, however, might be that children, unlike adults, do not have obesity-associated comorbidities such as hypertension, chronic kidney disease, type 2 diabetes, and cardiovascular disease which are important risk factors for severe symptomatic COVID-19 illness. Another interesting finding is that children with symptomatic COVID-19 illness were more likely to have received the influenza vaccine in the recent season contrary to recent reports suggesting that the influenza vaccination may reduce the risk of COVID-19 infection and severity.6 A larger sample size is needed to further assess this finding. A limitation of our study is that infection was based on a positive serology test and report of COVID-19 symptoms rather than by a nasal swab test for presence of virus. Most notably, we identified a novel association of decreased risk for COVID-19 infection to a common childhood asthma-associated 17q21 genotype. Asthma has not been a distinct risk factor for severe COVID-19 disease in children or adults,7 and the presence of asthma and allergies may even be protective.8 Steroid use, thought to be a factor for this protective effect,9 was not a confounder in our cohort. This did not include an analysis of systemic steroid use as only 9 of 186 children received a short burst of an oral corticosteroid. Thus, 17q21 asthma-risk genotypes may confer a protective effect against SARS-CoV-2 infection, particularly in children with asthma. It has been demonstrated that children with 17q21 asthma-risk genotypes, such as rs7216389, have lower sphingolipid synthesis.1, 10 Recently, two sphingolipids, sphingosine, and ceramide were shown to interfere with the uptake of SARS-CoV-2 viral particles into epithelial cell lines and primary human nasal cells in culture whereby sphingosine blocked and ceramide facilitated viral entry.11 Therefore, genetic 17q21 variations associated with asthma risk in children (T risk allele) and higher ORMDL3 expression linked to lower sphingolipid synthesis may in turn lead to decreased viral entry. Although a larger replication cohort is needed to validate our findings, our study lays the initial groundwork for uncovering a mechanism for why children with asthma are not as vulnerable to the SARS-CoV-2 virus as originally expected. Moreover, future mechanistic studies are needed to understand how asthma-associated alterations in sphingolipid levels might be implicated in COVID-19 pathology. Ioulia Gourari: Conceptualization (lead); investigation (lead); methodology (lead); project administration (equal); supervision (equal); visualization (equal); writing – original draft (lead); writing – review & editing (lead). Rika Gomi: Investigation (lead); project administration (equal); resources (equal); supervision (equal); visualization (equal); writing – review & editing (equal). Madeline Young: Investigation (equal); visualization (equal); writing – review & editing (equal). Geancarlo Jordan: Investigation (equal); visualization (equal); writing – review & editing (equal). Madeline Liongson: Investigation (equal); visualization (equal); writing – review & editing (equal). Andrea Heras: Conceptualization (equal); investigation (equal); visualization (equal); writing – review & editing (equal). Linda M. Gerber: Data curation (lead); formal analysis (lead); software (lead); visualization (equal); writing – review & editing (equal). Charlene Thomas: Data curation (lead); formal analysis (lead); software (lead); visualization (equal); writing – review & editing (equal). Kalliope Tsirilakis: Conceptualization (equal); investigation (equal); visualization (equal); writing – review & editing (equal). Jennie Ono: Conceptualization (equal); investigation (equal); visualization (equal); writing – review & editing (equal). Pramod Narula: Conceptualization (equal); investigation (equal); visualization (equal); writing – review & editing (equal). Thomas Ketas: Data curation (lead); investigation (lead); methodology (lead); resources (lead); visualization (equal); writing – review & editing (equal). John P. Moore: Data curation (lead); investigation (lead); methodology (lead); Resources (lead); visualization (equal); writing – review & editing (equal). Stefan Worgall: Conceptualization (lead); investigation (lead); methodology (lead); project administration (lead); supervision (lead); visualization (lead); writing – original draft (lead); writing – review & editing (lead). Perdita Permaul: Conceptualization (lead); investigation (lead); methodology (lead); project administration (lead); supervision (lead); visualization (lead); writing – original draft (lead); writing – review & editing (lead). This study received support from NewYork-Presbyterian Hospital (NYPH) and Weill Cornell Medical College (WCMC), including the Clinical and Translational Science Center (CTSC) (UL1 TR000457) and Joint Clinical Trials Office (JCTO). This research is supported by NIH K23 AI123517 (P. P); R01 AI36082 and P01 AI110657 (J. P. M); and KL2 TR0002385-05 (A. H). The authors declare no conflict of interest. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Asthma is the most common disease of childhood, with a disproportionate burden in inner-city populations.1 Within inner-city homes, specific aeroallergen exposures, particularly mouse and cockroach, have been associated with asthma morbidity.2,3 Inner-city schools have also been shown to be a significant source of allergen exposure contributing to asthma morbidity.4 The first School Inner-City Asthma Study (SICAS 1), occurring between 2008 and 2013, revealed an association between exposure to mouse allergen in schools and worsening asthma symptoms, independent of sensitization status or home environmental exposure.

BACKGROUND: Asthma is among the most common chronic diseases of children in the United States (US). Mold exposures have been linked to asthma development and exacerbation. In homes, mold exposures have been quantified using the Environmental Relative Moldiness Index (ERMI), and higher home ERMI values have been linked to occupant asthma. OBJECTIVE: In this analysis of the School Inner-City Asthma Study (SICAS), we aimed to evaluate the ERMI's applicability to measuring mold in schools compared with homes and to examine the prevalence of asthma in relationship to students' demographics and the physical characteristics of school buildings. METHODS: Northeastern US schools (n = 32) and homes (n = 33) were selected, and the 36 ERMI molds were quantified in a dust sample from each classroom (n = 114) or home. School building characterifrom SICAS. Asthma prevalence and student demographics data were obtained from government websites. Linear regression and mixed models were fit to assess the association of the current asthma prevalence and physical characteristics of the school, make-up of the student body, and the ERMI metric. RESULTS: Levels of outdoor group 2 molds were significantly (P <.01) greater in schools compared with homes. The presence of air-conditioning in school buildings correlated significantly (P = .02) with lower asthma prevalence. CONCLUSION: The prevalence of asthma in student bodies is associated with many factors in schools and homes. (C) 2020 American Academy of Allergy, Asthma & Immunology