Methylation-driven mechanisms of allergic rhinitis during pollen and non-pollen seasons using integrated bioinformatics analysis.

Background: Allergic rhinitis (AR) is a widespread allergic airway disease that results from a complex interplay between genetic and environmental factors and affects approximately 10%-40% of the global population. Pollen is a common allergen, and exposure to pollen can cause epigenetic changes. However, the mechanism underlying pollen-induced DNA methylation changes and their potential effects on the allergic march are still unclear. The purpose of this study was to explore the methylation-driven mechanisms of AR during the pollen and non-pollen seasons using bioinformatics analysis and to investigate their relationship with asthma. Methods: We downloaded DNA methylation and gene expression data from the GEO database (GSE50387: GSE50222, GSE50101) and identified differentially methylated positions (DMPs) and differentially expressed genes (DEGs) during the pollen and non-pollen seasons using the CHAMP and limma packages. Through correlation analysis, we identified methylation-driven genes and performed pathway enrichment analysis to annotate their functions. We incorporated external data on AR combined with asthma (GSE101720) for analysis to identify key CpGs that promote the transformation of AR to asthma. We also utilized external data on olive pollen allergy (GSE54522) for analysis to validate the methylation-driven genes. Weighted correlation network analysis (WGCNA) was employed to identify gene modules significantly correlated with pollen allergy. We extracted genes related to the key methylation-driven gene ZNF667-AS1 from the significant module and performed pathway intelligent clustering using KOBAS-i. We also utilized gene set enrichment analysis to explore the potential function of ZNF667-AS1. Results: We identified 20 and 24 CpG-Gene pairings during the pollen and non-pollen seasons. After incorporating external data from GSE101720, we found that ZNF667-AS1 is a key gene that may facilitate the transformation of AR into asthma during the pollen season. This finding was further validated in another external dataset, GSE54522, which is associated with pollen allergy. WGCNA identified 17 modules, among which the blue module showed significant correlation with allergies. ZNF667-AS1 was located in the blue module. We performed pathway analysis on the genes correlated with ZNF667-AS1 extracted from the blue module and identified a prominent cluster of pathways in the KOBAS-i results, including Toll-like receptor (TLR) family, MyD88, MAPK, and oxidative stress. Gene set enrichment analysis around cg05508084 (paired with ZNF667-AS1) also indicated its potential involvement in initiating and modulating allergic inflammation from the perspective of TLR and MAPK signaling. Conclusion: We identified methylation-driven genes and their related pathways during the pollen and non-pollen seasons in patients with AR and identified key CpGs that promote the transformation of AR into asthma due to pollen exposure. This study provides new insights into the underlying molecular mechanisms of the transformation of AR to asthma.

Impact of pollen season and viral disease COVID-19 on respiratory function of the adult population in Eastern Slovakia: analysis of spirometric data and results of a questionnaire survey.

INTRODUCTION: Asthma is a chronic heterogeneous disease with characteristic symptoms, but with proper treatment the patient can lead a full life. In patients with allergic asthma, symptoms appear after irritation with an allergen, most often in the pollen season. In 2019, the viral disease COVID-19 appeared, which, especially in people with asthma, led not only to an asthma attack, but also to other serious diseases. METHODS: The main aim was to investigate differences in patients' health status by comparing spirometric values in and out of pollen season (A), spirometric values before and after COVID-19 viral illness (B) and an anonymous questionnaire (C). Spirometric values were recorded in each patient (control group - patients diagnosed with asthma, research group - patients after overcoming COVID-19 disease) in 3 cycles, namely (in the pollen period, in the non-pollen period and after overcoming COVID-19 disease - at an interval of 2 months after a negative PCR test). RESULTS: We observed significant results during the individual spirometry performed (A) during the pollen season and non-pollen season. We observed the same in patients after they received COVID-19 treatment (B). Patients were also asked questions regarding family history, symptoms and their variability, worsening of the condition or correct inhalation technique (C). CONCLUSION: Our research shows that the PEF parameter is most affected by the pollen and non-pollen season in asthmatic patients. Significant differences in PEF parameter were observed between genders, where we observed highly significant statistical significance of PEF parameter in pollen and non-pollen season in females.

Pollen Sensitization Can Increase the Allergic Reaction to Non-Cross-Reactive Allergens in a Soy-Allergic Patient.

During and after the pollen season, an increase in food-triggered allergic symptoms has been observed in pollen-food syndrome patients, possibly due to seasonal boosting of pollen-IgE levels. It has been suggested that consumption of birch-pollen-related foods plays a role in seasonal allergenic inflammation. However, whether this increased pollen sensitization during the pollen season can also affect the allergenicity of allergens that are non-cross-reactive with birch pollen remains in question. This study presents the case of a patient with soy allergy and pollinosis, who experiences worsening of gastrointestinal (GI) symptoms during the birch pollen season even though the eliciting food factor does not cross-react with birch pollen allergens and their homologs (e.g., Bet v 1 and Gly m 4). The results showed a notable increase in sIgE for Gly m 4 (3.3 fold) and Bet v 1 (2.6 fold) during the birch pollen season compared to outside the birch pollen season, while Gly m 5 and Gly m 6 showed only a slight increase (1.5 fold). The basophil activation test (BAT) showed that in this patient Gly m 5 and Gly m 6 are clinically relevant soy allergens, which correlates with the reported clinical symptoms to processed soy. Moreover, the BAT against raw soy shows an increase in basophil activation during the birch pollen season and a negative basophil activation result outside the birch pollen season. Thus, the worsening of GI symptoms could possibly be due to an increase in IgE receptors, an over-reactive immune system, and/or significant intestinal allergic inflammation. This case highlights the importance of including allergens that do not cross-react with birch pollen and using a functional assay such as the BAT to evaluate clinical relevance when assessing birch pollen seasonal influence on soy allergenicity.

Clinical response to varying pollen exposure in allergic rhinitis in children in The Netherlands.

BACKGROUND: Allergic rhinitis (AR) affects 10-15% of children. Symptoms in seasonal AR are influenced by pollen exposure. Pollen counts vary throughout the pollen season and therefore, symptom severity fluctuates. This study investigates the correlation between pollen concentration and symptom load in children with AR in The Netherlands. METHODS: A secondary analysis was performed in a study determining the most effective treatment for children with seasonal AR. Symptoms were measured during three months in 2013 and 2014 using a daily symptom diary. The pollen concentration was measured with a Hirst type volumetric spore trap sampler. A correlation coefficient was calculated for the correlation between the pollen concentration and the mean daily symptom score. The study protocol was approved by the medical ethical review committee of the Erasmus MC and is incorporated in the International Clinical Trials Registry Platform (EUCTR2012-001,591-11-NL). RESULTS: In 2014, the correlation coefficient for birch pollen concentration and symptom score was 0.423 (p = 0.000). The correlation coefficient for grass pollen concentration and symptom score was 0.413 (p = 0.000) and 0.655 (p = 0.000) in 2013 and 2014, respectively. A delayed correlation between the birch pollen concentration and the symptom scores was seen up to two days after the pollen measurement (0.151, p = 0.031). For grass pollen this effect lasted up to three days after the pollen measurement (0.194, p = 0.000). CONCLUSION: We found comparable correlations between symptom score and pollen concentration as found by EAACI. Birch and grass pollen have an elongated influence on symptom score of several days. This implies patients need to continue on demand medication longer after a measured pollen peak.

Influence of meteorological factors on the dynamics of hazel, alder, birch and poplar pollen in the 2021 season in Kielce, Poland.

INTRODUCTION AND OBJECTIVE: Hazel, alder, birch, and poplar pollen allergens are a common cause of pollen allergies. In a temperate climate, wind-pollinated plants are characterized by a seasonal pollen release cycle associated with the seasons of the year and weather conditions. Therefore, the aim of the present study was to assess the course of pollen seasons of some allergenic plants and to determine the effect of meteorological factors on the content of pollen grains in the bioaerosol in 2021 in Kielce, Poland. MATERIAL AND METHODS: In relation to selected meteorological parameters, the length of the total and main pollen season, the sum of daily pollen grain concentrations in the season, the peak pollen concentration, and the number of days with values exceeding the species-specific threshold concentrations, were determined. RESULTS: Hazel and alder pollen were the first to appear in the air of Kielce. The longest pollen season was observed for birch, while hazel was characterized by the shortest season. The alder pollen release was intense, with the highest maximum concentration of pollen grains. The study revealed a significant influence of the maximum air temperature on the dynamics of hazel, alder and poplar pollen release. Birch pollen release was significantly correlated with the average air humidity. The concentration of alder and birch pollen grains also depended on rainfall intensity. The wind force had a significant impact on the pollen season of plants. CONCLUSIONS: There were various relationships between the meteorological factors and the content of pollen grains in the air. The wind speed and temperature had the greatest impact on plant pollen release, with birch and alder being particularly sensitive to weather conditions.

Birch pollen, air pollution and their interactive effects on airway symptoms and peak expiratory flow in allergic asthma during pollen season - a panel study in Northern and Southern Sweden.

BACKGROUND: Evidence of the role of interactions between air pollution and pollen exposure in subjects with allergic asthma is limited and need further exploration to promote adequate preventive measures. The objective of this study was to assess effects of exposure to ambient air pollution and birch pollen on exacerbation of respiratory symptoms in subjects with asthma and allergy to birch. METHODS: Thirty-seven subjects from two Swedish cities (Gothenburg and Umeå) with large variation in exposure to both birch-pollen and air pollutants, participated in the study. All subjects had confirmed allergy to birch and self-reported physician-diagnosed asthma. The subjects recorded respiratory symptoms such as rhinitis or eye irritation, dry cough, dyspnoea, the use of any asthma or allergy medication and peak respiratory flow (PEF), daily for five consecutive weeks during two separate pollen seasons and a control season without pollen. Nitrogen oxides (NOx), ozone (O3), particulate matter (PM2.5), birch pollen counts, and meteorological data were obtained from an urban background monitoring stations in the study city centres. The data were analysed using linear mixed effects models. RESULTS: During pollen seasons all symptoms and medication use were higher, and PEF was reduced in the subjects. In regression analysis, exposure to pollen at lags 0 to 2 days, and lags 0 to 6 days was associated with increased ORs of symptoms and decreased RRs for PEF. Pollen and air pollution interacted in some cases; during low pollen exposure, there were no associations between air pollution and symptoms, but during high pollen exposure, O3 concentrations were associated with increased OR of rhinitis or eye irritation, and PM2.5 concentrations were associated with increased ORs of rhinitis or eye irritation, dyspnea and increased use of allergy medication. CONCLUSIONS: Pollen and air pollutants interacted to increase the effect of air pollution on respiratory symptoms in allergic asthma. Implementing the results from this study, advisories for individuals with allergic asthma could be improved, minimizing the morbidities associated with the condition.

Omalizumab is effective in the preseasonal treatment of seasonal allergic rhinitis.

BACKGROUND: To date no study has evaluated the efficacy of preseasonal omalizumab therapy with cost effective dose and at appropriate time point compared with standard medication in seasonal allergic rhinitis (SAR) patients. METHODS: This was a prospective randomized controlled open-label single-centre trial. 32 SAR patients were randomized to receive a single injection of omalizumab 300-mg approximately two weeks before start of the pollen period (PP) or medication therapy. All patients completed daily questionnaires; recording symptoms, medication use and quality of life (QoL) throughout the observation period. The primary efficacy parameter was the mean daily Combined Symptom and Medication Score (CSMS). RESULTS: Preseasonal omalizumab significantly reduced the changes of mean daily CSMS of nose during the PP (p < 0.001), peak pollen period (PPP) and PP after PPP (PPP-PP) (p = 0.002) and Post-PP (p = 0.009) compared to standard medication. The proportion of allergy symptoms-relieving medication-free days during PPP-PP was also significantly higher in preseasonal omalizumab-treated group (76.2(16.7-98.8))% than in medication-treated group (19.0(0-71.4))% (p = 0.030). Omalizumab could achieve the same nasal symptom control during the entire pollen season and better eye symptoms relieving results in PP (p = 0.046) and PPP-PP (p = 0.004) than medication treatment. Significantly greater improvement in QoL was also obtained with omalizumab-pretreatment during the PP (p = 0.037) and PPP-PP (p = 0.004). CONCLUSIONS: Administration of a single injection of 300 mg omalizumab two weeks before start of the pollen season achieves better overall control of symptoms and QoL, with significantly reduced allergy symptoms-relieving medication usage, compared with standard pharmacotherapy in SAR patients.

Very high concentrations of birch pollen in the air of selected Polish cities in 2022 - clinical implications.

INTRODUCTION: In the Polish population, the most common cause of allergic rhinitis (AR) in the spring is birch pollen. AIM: The aim of this study was to assess the basic characteristics of the birch pollen season in selected cities in central and northern Poland including Warsaw, Piotrkow Trybunalski, and Bydgoszcz in 2022, considering their clinical implications. MATERIAL AND METHOD: Pollen monitoring was conducted using the volumetric method with the Hirst-type continuous volumetric sampler. Measurements were taken in 7-day cycles, and the microscopic analysis was performed for each 24-hour period. Results During the studied period, birch pollen posed a threat in the 2nd and 3rd decades of April and the 1st and 2nd decades of May. The birch pollination intensity was reflected by the very high values of maximum average daily pollen concentration 4102 pollen/m3 in Warsaw, 4389 pollen/m3 in Piotrkow Trybunalski, 3832 pollen/m3 in Bydgoszcz and the sum of the average daily pollen concentrations (i.e. Annual Pollen Integral, APIn) from 32439 in Bydgoszcz to 37638 in Warsaw, and long periods of exposure to high concentrations (2930 days). CONCLUSIONS: The pollen season 2022 is part of an alternating 2-year cycle of the birch pollen season intensity. The variability of parameters describing the dynamics of pollen seasons over years makes it necessary to monitor information on the pollen concentration in the air during the pollen season, both by the patients with inhalant allergy and their physicians.

Comparative analysis of chronic rhinitis patient profiles during autumn pollen season between grassland and non-grassland cities in North China.

BACKGROUND: The symptoms of patients with respiratory disease are influenced by local environmental factors. The incidence of allergic rhinitis in grassland areas was significantly higher than that in non-grassland areas. We aimed to compare the profiles of chronic rhinitis patients obtained during the autumn pollen season in Baotou (grassland city) and Beijing (non-grassland city), China. METHODS: Questionnaire surveys and allergen testing were conducted on 1170 and 1232 patients with chronic rhinitis visiting the Second Affiliated Hospital of Baotou Medical College and Beijing Tongren Hospital, respectively, during the autumn pollen period. Information regarding medical history, severity of symptoms, and diagnosis and treatment was collected. RESULTS: More patients with moderate to severe chronic rhinitis and asthma (both, P < 0.001) were present in Baotou than in Beijing. Mugwort was the most abundant allergen in both regions, but the number of patients sensitized to outdoor allergens in Baotou was higher than that in Beijing (P < 0.001). Indoor allergens in Beijing represented a considerable proportion of allergens, especially dust mites (33.4%). For patients with allergic rhinitis, nasal congestion, nasal itching, and runny nose were more severe in Baotou than in Beijing (P < 0.001). In both Baotou and Beijing, allergy (P < 0.001 vs. P = 0.004) and combined asthma (P = 0.049 vs. P = 0.005) were common factors affecting the severity of the clinical symptoms chronic rhinitis. In Baotou, age (rs = 0.195, P < 0.001) and family allergy history (P = 0.010) were also associated with symptom severity. Although significantly more patients in Baotou received oral antihistamines, nasal corticosteroids, and surgical treatment than in Beijing (P < 0.001), the number of people receiving allergy immunotherapy in Baotou was lower (P = 0.004) and post-treatment symptom control was worse (P < 0.001) that that in Beijing. CONCLUSIONS: During the pollen period, there were significant differences in the allergen spectrum between Baotou and Beijing. Allergy and combined asthma were common factors affecting the severity of clinical symptoms. Patients in Baotou presented with more severe clinical symptoms that were not satisfactorily managed due to the impact of pollen exposure, inconsistent access to care, and differing treatment modalities.

Coincidence of pollen season and coronavirus disease 2019 pandemic: less time outdoors - lesser allergy symptoms in 2020.

BACKGROUND: This year, pollen season coincided with the first wave of the coronavirus disease 2019 pandemic. Strict preventive measures have been implemented during April and May and then a normalization phase started in our country in June. Our aim is to evaluate the effect of preventive measures during the pandemic process on allergic airway disease symptoms. METHODS: A prospective questionnaire-based study was planned and a questionnaire form was sent to the cell-phones of the subjects with pollen allergy followed in our clinic. Number of airborne grass pollens was determined by Burkard volumetric 7-day spore trap. RESULTS: A total of 222 pollen allergic patients were included in the study. At the beginning of the pandemic, majority of the subjects were spending time mostly indoors. The rate of home-office workers gradually decreased and the rate of office workers and the number of days at work increased from April to June, significantly. Nasal and ocular symptoms of the patients, also increased in June compared to April and May and, approximately one-third of the patients had less symptoms when compared to the same period of the previous year. The rates of using a face mask and taking a shower on return home were high among the subjects during all season. CONCLUSION: Our study showed that spending less time outside during the pollen season and wearing a mask outdoors reduces exposure to pollens and causes a reduction in symptoms. Thus, strict application of measures that cannot be applied in daily practice can make a significant contribution to the management of seasonal allergic rhinitis.

Does airborne pollen influence COVID-19 outbreak?

The fast spread of SARS-CoV-2 presented a worldwide challenge to public health, economy, and educational system, affecting wellbeing of human society. With high transmission rates, there are increasing evidences of COVID-19 spread via bioaerosols from an infected person. The current review was conducted to examine airborne pollen impact on COVID-19 transmission and to identify the major gaps for post-pandemic research. The study used all key terms to identify revenant literature and observation were collated for the current research. Based on existing literature, there is a potential association between pollen bioaerosols and COVID-19. There are few studies focusing the impact of airborne pollen on SARS-CoV-2, which could be useful to advance future research. Allergic rhinitis and asthma patients were found to have pre-modified immune activation, which could help to provide protection against COVID-19. However, does airborne pollen acts as a potent carrier for SARS-CoV-2 transport, dispersal and its proliferation still require multidisciplinary research. Further, a clear conclusion cannot be drawn due to limited evidence and hence more research is needed to show how pollen bioaerosols could affect virus survivals. The small but growing literature review focuses on searching for every possible answer to provide additional security layers to overcome near future corona-like infectious diseases.

Multi-decade changes in pollen season onset, duration, and intensity: A concern for public health?

Longitudinal shifts in pollen onset, duration, and intensity are public health concerns for the growing number of individuals with pollen sensitization. National analyses of long-term pollen changes are influenced by how a plant's main pollen season (MPS) is defined. Prior Swiss studies have inconsistently applied MPS definitions, leading to heterogeneous conclusions regarding the magnitude, directionality, and significance of multi-decade pollen trends. We examined national pollen data in Switzerland between 1990 and 2020, applying six MPS definitions (2 percentage-based and 4 threshold-based) to twelve relevant allergenic plants. We analyzed changes in pollen season using both linear regression and locally estimated scatterplot smoothing (LOESS). For 4 of the 12 plant species, there is unanimity between definitions regarding earlier onset of pollen season (p < 0.05), with magnitude of 31-year change dependent on specific MPS definition (hazel: 9-18 days; oak: 5-13 days; grasses: 8-25 days; and nettle/hemp: 6-25 days). There is also consensus (p < 0.05) for modified MPS duration among hazel (21-104% longer), nettle/hemp (8-52% longer), and ash (18-38% shorter). Between-definition agreement is highest for MPS intensity analysis, with consensus for significant increases in seasonal pollen quantity (p < 0.05) among hazel, birch, oak, beech, and nettle/hemp. The largest relative intensification is noted for hazel (110-146%) and beech (162-237%). LOESS analysis indicates that these multi-decade pollen changes are typically nonlinear. The robustness of MPS definitions is highly dependent on annual pollen accumulation, with definition choice particularly influential for long-term analysis of low-pollen plants such as ragweed. We identify systematic differences between MPS definitions and suggest future aerobiologic studies apply multiple definitions to minimize bias. In summary, national pollen onset, duration, and intensity have shifted for some plants in Switzerland, with MPS definition choice affecting magnitude and significance of these variations. Future public health research can determine whether these temporal and quantitative pollen changes correlate with longitudinal differences in population pollen sensitization.

Children with atopic eczema experiencing increased disease severity in the pollen season more often have hay fever at a young age and a dark skin type.

Children with atopic eczema are known to experience seasonal variations in disease severity, with winter being the season in which severity generally increases. There is a lack of knowledge about the subgroup of children that experiences increased severity in spring and summer months. We aimed to investigate which phenotype characteristics best describe children flaring in the pollen season. A retrospective database analysis was conducted, including 110 children with difficult-to-treat atopic eczema aged 0-17 years. Relevant outcome parameters were extracted from medical records. In our population, 36% (n = 40/110) of children reported flares of atopic eczema in the pollen season. These children were more often sensitized to one or more types of pollen (73% [n = 29/40] vs. 28% [n = 10/36], p < 0.0001) and had more patient-reported hay fever (70% [n = 28/40] vs. 19% [n = 7/36], p < 0.0001), compared with children who do not flare in the pollen season. Moreover, children flaring in the pollen season more often had a dark skin type (78% [n = 31/40] vs. 44% [n = 16/36], p = 0.003). Based on stepwise multivariable analyses, children flaring in the pollen season were characterized by the combination of younger age, hay fever, and dark skin type (C-statistic: 0.86). In conclusion, patient-reported flares in spring and summer are experienced by one-third of children with difficult-to-treat atopic eczema. This phenotype can be characterized as young children having hay fever and a dark skin type and can be identified based on clinical parameters alone without the need to perform immunoglobulin E blood testing or skin prick tests.

A First Pre-season Pollen Transport Climatology to Bavaria, Germany.

Climate impacts on the pollen season are well-described however less is known on how frequently atmospheric transport influences the start of the pollen season. Based on long-term phenological flowering and airborne pollen data (1987-2017) for six stations and seven taxa across Bavaria, Germany, we studied changes in the pollen season, compared pollen and flowering season start dates to determine pollen sources, and analyzed the likelihood of pollen transport by HYSPLIT back trajectories. Species advanced their pollen season more in early spring (e.g., Corylus and Alnus by up to 2 days yr-1) than in mid spring (Betula, Fraxinus, Pinus); Poaceae and Artemisia exhibited mixed trends in summer. Annual pollen sums mainly increased for Corylus and decreased for Poaceae and Artemisia. Start of pollen season trends largely deviated from flowering trends, especially for Corylus and Alnus. Transport phenomena, which rely on comparisons between flowering and pollen dates, were determined for 2005-2015 at three stations. Pre-season pollen was a common phenomenon: airborne pollen was predominantly observed earlier than flowering (median 17 days) and in general, in 63% of the cases (except for Artemisia and Poaceae, and the alpine location) the pollen sources were non-local (transported). In 54% (35%) of these cases, back trajectories confirmed (partly confirmed) the pre-season transport, only in 11% of the cases transport modeling failed to explain the records. Even within the main pollen season, 70% of pollen season start dates were linked to transport. At the alpine station, non-local pollen sources (both from outside Bavaria as well as Bavarian lowlands) predominated, in only 13% of these cases transport could not be confirmed by back trajectories. This prominent role of pollen transport has important implications for the length, the timing, and the severity of the allergenic pollen season, indicating only a weak dependency on flowering of local pollen sources.

50 Years of Pollen Monitoring in Basel (Switzerland) Demonstrate the Influence of Climate Change on Airborne Pollen.

Climate change and human impact on vegetation modify the timing and the intensity of the pollen season. The 50 years of pollen monitoring in Basel, Switzerland provide a unique opportunity to study long-term changes in pollen data. Since 1969, pollen monitoring has been carried out in Basel with a Hirst-type pollen trap. Pollen season parameters for start dates, end dates and duration were calculated with different pollen season definitions, which are commonly used in aerobiology. Intensity was analyzed by the annual pollen integral (APIn), peak value and the number of days above specific thresholds. Linear trends were calculated with the non-parametric Mann Kendall method with a Theil-Sen linear trend slope. During the last 50 years, linear increase of the monthly mean temperatures in Basel was 0.95-1.95°C in the 3 winter months, 2-3.7°C in spring months and 2.75-3.85°C in summer months. Due to this temperature increase, the start dates of the pollen season for most of the spring pollen species have advanced, from 7 days for Poaceae to 29 days for Taxus/Cupressaceae. End dates of the pollen season depend on the chosen pollen season definition. Negative trends predominate, i.e., the pollen season mostly ends earlier. Trends in the length of the pollen season depend even more on the season definitions and results are contradictory and often not significant. The intensity of the pollen season of almost all tree pollen taxa increased significantly, while the Poaceae pollen season did not change and the pollen season of herbs decreased, except for Urticaceae pollen. Climate change has a particular impact on the pollen season, but the definitions used for the pollen season parameters are crucial for the calculation of the trends. The most stable results were achieved with threshold definitions that indicate regular occurrence above certain concentrations. Percentage definitions are not recommended for trend studies when the annual pollen integral changed significantly.

Polyvalent Mechanical Bacterial Lysate Administration Improves the Clinical Course of Grass Pollen-Induced Allergic Rhinitis in Children: A Randomized Controlled Trial.

BACKGROUND: Recent studies highlight the immunoregulatory potential of bacterial lysates, indicating their potential use in the prevention and treatment of allergic diseases. OBJECTIVE: To investigate the clinical efficacy of polyvalent mechanical bacterial lysates (PMBLs) in children with grass pollen-induced allergic rhinitis. METHODS: Seventy children with seasonal allergic rhinitis were enrolled to this study and were randomly assigned to the PMBL and placebo groups. Severity of seasonal allergic rhinitis symptoms was assessed by the total nasal symptom score, total ocular symptom score, and visual analogue scale. During 3 visits, peak nasal inspiratory flow was measured, and nasal smears for the presence of eosinophils and nasal lavage fluids for the presence of allergen-specific IgE against timothy grass pollen allergens were sampled. RESULTS: A statistically significant decrease in total nasal symptom score (P = .001), total ocular symptom score (P = .04), and visual analogue scale score for nasal and eye symptoms (P < .001 and P < .001, respectively) and an increase in peak nasal inspiratory flow (P = .04) were observed in the PMBL group versus the placebo group. During the grass pollen season, an increase and then a decrease in the number of eosinophils in nasal smears was observed in both groups; however, the number of eosinophils was significantly lower in the PMBL group versus the placebo group. No significant changes in allergen-specific IgE concentrations were observed in the PMBL group, whereas in the placebo group a statistically significant increase in allergen-specific IgE concentration was observed. CONCLUSIONS: Sublingual administration of PMBLs during the grass pollen season offers significant efficacy in alleviating seasonal allergic rhinitis symptoms in children sensitized to grass pollen allergens. PMBLs probably affect mucosal immunity, weakening the response of TH2 cells.

Cognitive dysfunction and quality of life during pollen season in children with seasonal allergic rhinitis.

BACKGROUND: Allergic rhinitis often gives rise to impaired quality of life and is believed to also affect cognitive function. We aimed to examine whether cognitive functions were impaired during grass pollen season in symptomatic allergic children and to relate the degree of impairment to quality of life and biomarkers related to stress and inflammation. METHODS: Forty-three grass pollen-allergic children (age 8-17 years) with non-satisfactory effect of medication (antihistamines and nasal steroids daily) during previous seasons were included. In addition, 26 matched non-allergic children were included as controls. Both groups performed cognitive tests (CANTAB) and completed Quality of Life questionnaires outside and during the pollen season. Blood samples were collected and analyzed for stress and inflammatory biomarkers. Pollen level was measured daily. RESULTS: Impaired cognitive function was found in spatial working memory, where the allergic group made more errors compared to the non-allergic group during pollen season, but not off-season. No significant differences could be seen between the allergic group and the controls in the other tests investigating visual memory or attention. Quality of health questionnaires revealed more symptoms and impaired quality of life in allergic compared to non-allergic children, and increased symptoms in allergic children were associated with longer reaction time for simple movement during pollen season. No differences in stress or inflammatory biomarkers could be found between the groups. CONCLUSION: Cognitive function was affected during pollen season in pollen-allergic children, and the more symptoms the allergic children had, the longer the reaction time in the cognitive tests.

Extension of WRF-Chem for birch pollen modelling-a case study for Poland.

In recent years, allergies due to airborne pollen allergens have shown an increasing trend, along with the severity of allergic symptoms in most industrialized countries, while synergism with other common atmospheric pollutants has also been identified as affecting the overall quality of citizenly life. In this study, we propose the state-of-the-art WRF-Chem model, which is a complex Eulerian meteorological model integrated on-line with atmospheric chemistry. We used a combination of the WRF-Chem extended towards birch pollen, and the emission module based on heating degree days, which has not been tested before. The simulations were run for the moderate season in terms of birch pollen concentrations (year 2015) and high season (year 2016) over Central Europe, which were validated against 11 observational stations located in Poland. The results show that there is a big difference in the model's performance for the two modelled years. In general, the model overestimates birch pollen concentrations for the moderate season and highly underestimates birch pollen concentrations for the year 2016. The model was able to predict birch pollen concentrations for first allergy symptoms (above 20 pollen m-3) as well as for severe symptoms (above 90 pollen m-3) with probability of detection at 0.78 and 0.68 and success ratio at 0.75 and 0.57, respectively for the year 2015. However, the model failed to reproduce these parameters for the year 2016. The results indicate the potential role of correcting the total seasonal pollen emission in improving the model's performance, especially for specific years in terms of pollen productivity. The application of chemical transport models such as WRF-Chem for pollen modelling provides a great opportunity for simultaneous simulations of chemical air pollution and allergic pollen with one goal, which is a step forward for studying and understanding the co-exposure of these particles in the air.

Assessment of Google Trends terms reporting allergies and the grass pollen season in Ukraine.

BACKGROUND: Grass pollen allergy is an important trigger for the development of respiratory disorders. Defining the grass pollen season onset is critical for correct allergy diagnosis and personalized therapy. The development of a pan-European sentinel network for allergic diseases has raised the problem of translating the Google search terms into different European languages as well as defining specific pollen season characteristics in different regions. Grass pollen allergy was investigated due to high allergenicity and wide expansion of grass pollen in Europe. OBJECTIVES: The aim of this study was to examine which translations of "hay fever", "grass", and "rhinitis" could be used in the native Cyrillic languages, especially in Ukrainian and Russian, and to compare the seasonality of allergic respiratory queries in Ukraine with the grass pollen counts. METHODS: Google Trends (GT) was used to search Google queries concerning grass pollen allergy: "allergy", "hay fever", "runny nose", "grass", "asthma", and "pollen". The Cyrillic terms in Ukrainian and Russian were used. The search was done for the period from 2013 to 2017. Pollen collection from 2013 to 2016 was conducted using volumetric methods. Average daily temperatures were obtained from http://gismeteo.ua. Correlations were assessed by Spearman (R) test. RESULTS: The Ukrainian Google users searched the Cyrillic equivalents for "runny nose", "grass", and "asthma". Due to the GT queries profile, Ukraine had a "D" pattern according to the classification, developed by Bousquet J et al (2017). In Ukraine, the Poaceae pollen season generally occurred between the second ten-day period of May and the last ten-day period of July. The Poaceae pollen season started with a concentration of pollen grains of 8.0 m-3. This concentration provoked the growth of GT "grass", "allergy", "hay fever", and "asthma" queries. CONCLUSIONS: The terms "grass", "allergy", "hay fever", and "asthma" (in their Cyrillic equivalents) are required in Ukraine to account for the grass pollen exposure by GT. The study of GT may be a useful tool to make an assessment of the grass pollen season for the prevention and minimization of exposure to significant grass pollen concentrations.

Impact of air pollution on symptom severity during the birch, grass and ragweed pollen period in Vienna, Austria: Importance of O3 in 2010-2018.

Air pollution is a threat to the general population, especially to pollen allergy sufferers in urban environments. Different air quality parameters have hitherto been examined which add to the burden of pollen allergy sufferers. Parameters such as NO2, SO2, PM10, PM2.5, and O3 are supposed to have additional impact, not only on health in general (increase in asthma, allergy sensitization frequency), but also on pollen grains (increase of allergenicity). However, it remains unknown if those air quality parameters increase symptom severity during the pollen season. We selected the birch, grass, and ragweed pollen seasons as different time periods throughout the year and analyzed the relationship of symptom data to pollen, air quality, and meteorological data (temperature, relative humidity) for the metropolis of Vienna (Austria). A linear regression model was computed based on different symptom data, and both pollen and air quality data were tested simultaneously. Ozone was positively and significantly associated with symptom scores in all three seasons, whereas this was only rarely the case with other pollutants. Therefore, only ozone was selected for further analysis in a model including meteorological parameters. In this model, effect estimates of ozone were attenuated but remained significant for the grass pollen season. The lack of significance in the other seasons may be attributed to the less numerous symptom data entries and the shorter duration of the pollen seasons for birch and ragweed. All other air quality parameters usually showed lower concentrations during the pollen seasons and displayed little variation. This might explain the lack of a clear signal. Our results suggest that today's allergic population is already affected by air quality (rising O3 levels). Air quality should be considered as well in pollen information and pollen allergy studies in general because of its increasing importance in the light of global warming.