• Karatzas K, Katsifarakis N, Riga M, Werchan B, Werchan M, Berger U, Pfaar O, Bergmann KC. New European Academy of Allergy and Clinical Immunology definition on pollen season mirrors symptom load for grass and birch pollen-induced allergic rhinitis. Allergy. 2018 Sep;73(9):1851-1859. doi.org/10.1111/all.13487
  
  Abstract: Background: The use of allergen immunotherapy (AIT) for allergic rhinitis and its clinical efficacy in clinical trials depends on the effective determination of pollen allergen exposure time periods. We evaluate pollen data from Germany to examine the new definitions on pollen season and peak pollen period start and end as proposed by the European Academy of Allergy and Clinical Immunology (EAACI) in a recently published Position Paper. The aim was to demonstrate the ability of these definitions to mirror symptom loads for grass and birch pollen-induced allergic rhinitis based on real-life data. Methods: Data coming from four pollen monitoring stations in the Berlin and Brandenburg area in Germany and for 3 years (2014-2016) were used to investigate the correlation of season definitions, birch and grass pollen counts and total nasal symptom and mediation scores as reported by patients in "Patients Hay fever Diaries" (PHDs). After the identification of pollen periods on the basis of the EACCI criteria, a statistical analysis was employed, followed by a detailed graphical investigation. Results: The analysis revealed that the definitions of pollen season as well as peak pollen period start and end as proposed by the EAACI are correlated to symptom loads for grass and birch pollen-induced allergic rhinitis reported by patients in PHDs. Conclusion: Based on our analysis, the validity of the EAACI definitions on pollen season is confirmed. Their use is recommended in future clinical trials on AIT as well as in daily routine for optimal patient care.

• Susanto NH, Schoos AM, Standl M, Lowe AJ, Dharmage SC, Svanes C, Salim A, von Berg A, Lehmann I, Rasmussen MA, Werchan M, Bergmann KC, Lodge C, Abramson MJ, Heinrich J, Bisgaard H, Erbas B. Environmental grass pollen levels in utero and at birth and cord blood IgE: Analysis of three birth cohorts. Environ Int. 2018 Oct;119:295-301. https://doi.org/10.1016/j.envint.2018.06.036
  
  Abstract: Background: Early life factors are associated with allergic respiratory diseases, but the role of high grass pollen concentrations during pregnancy and shortly after birth is not known. Objective: To assess outdoor levels of grass pollen during the intrauterine period and at birth during peak pollen season on cord blood IgE in birth cohorts. Methods: Three birth cohorts were included: MACS (n = 429), Australia; COPSAC 2000 (n = 200), Denmark; and LISA (n = 1968), Germany. Cord blood IgE was categorized (<0.5 kU/L, 0.5–1 kU/L, >1 kU/L) and dichotomized (high IgE ? 0.5 kU/L). Birth during the grass pollen season months and cumulative exposure to outdoor grass pollen counts during pregnancy with cord blood IgE were analysed using multinomial regression and analysed in meta-analysis using binomial regression adjusted for potential confounders. Results: Birth during the grass pollen season had higher pooled odds of cord blood IgE >0.5 kU/L 1.37 (95% CI 1.06, 1.77) in a meta-analysis with little heterogeneity between the three cohorts. Cumulative exposure to outdoor grass pollen counts during the entire pregnancy was associated with slightly lower pooled odds but significant (OR = 0.98, 95% CI: 0.96 to 0.99). Conclusions: Birth during grass pollen seasons were associated with increased risk of high cord blood IgE in cities from both hemispheres, but high pollen loads in the environment during the entire pregnancy appeared protective. As IgE responses develop during the first months of life, our study findings provide new insights into the mechanisms of grass pollen exposure at birth and shortly after on possible allergic respiratory diseases.

• Karatzas, K., Papamanolis, L., Katsifarakis, N. et al. Google Trends reflect allergic rhinitis symptoms related to birch and grass pollen seasons. Aerobiologia 34, 437–444 (2018). doi.org/10.1007/s10453-018-9536-4
  
  Abstract: Google Trends (GT) describes the variation of the relevant interest of internet searches toward medical conditions and related symptoms. Allergic rhinitis symptom levels result from the intensity of exposure to aeroallergens in combination with relevant medication use. We analyze data from Germany to examine the relationship between hay fever-related Google search terms, symptom levels, medication use, and pollen count levels. For doing so, we also employ the new definitions on pollen season and peak pollen period start and end as proposed by the European Academy of Allergy and Clinical Immunology in a recently published position paper. We extract GT data for a number of search terms related to allergic rhinitis for Germany. We use total nasal symptom and mediation scores as reported by patients via a patient hay fever diary in the Berlin and Brandenburg areas in Germany for 3 years (2014–2016), accompanied by pollen data. Then a Pearson and Spearman correlation analysis is performed between symptom data and GT data. A graphical analysis is conducted, and the identification of pollen season and peak pollen periods is done based on the EAACI criteria. The analysis reveals that GT data are highly correlated with symptom levels and follow peak pollen period start–end, concerning grass and birch pollen-induced allergic rhinitis symptoms. GT data can be used as a proxy for the identification of the onset and variation of nasal symptom and medication score for allergic rhinitis sufferers.

Werchan, B., Werchan, M., Mücke, HG. & Bergmann, KC. Spatial distribution of pollen-induced symptoms within a large metropolitan area—Berlin, Germany. Aerobiologia (2018) 34: 539. doi.org/10.1007/s10453-018-9529-3&nbsp;

• Abstract: Large spatial differences in the distribution of three allergologically relevant pollen types for Central Europe—birch, grass, and mugwort—are revealed within a large metropolitan area—Berlin, Germany. The purpose of the study is an examination of the hypothesis that these different pollen exposure conditions can cause different degrees of pollen-induced symptoms within the city. Pollen data from 14 gravimetric traps and one volumetric trap in Berlin and anonymously reported pollen-induced symptom data from the online-based self-documentation tool “Patient’s Hayfever Diary” (PHD) are used for the analysis of temporal and spatial variations of the severity of the overall total symptoms. Geographically localised symptom data are linked to the nearest pollen trap. Statistical analysis is performed using Kendall’s Tau-b. Higher amounts of monitored birch and grass pollen in the peripheral areas of Berlin induce stronger symptoms in PHD users located within suburbs than those located in the city centre. There is no statistical relationship between the varying presence of mugwort pollen in the air and the severity of symptoms. Spatial differences in the pollen-induced symptom severity within a large city coinciding with spatial differences in birch and grass pollen depositions are shown for the first time. Therefore, pollen data from a single trap may not provide an appropriate explanation for differences in pollen-induced symptoms across the city. More detailed and reliable information about the exposure to allergenic pollen can be addressed by installing further traps in order to improve the knowledge about pollen exposure within cities.

• Werchan, M., Werchan, B. & Bergmann, KC. Deutscher Pollenflugkalender 4.0 Update mit Messdaten von 2011 bis 2016. Allergo J (2018) 27: 18. doi.org/10.1007/s15007-018-1578-y

• Werchan, M., Sehlinger, T., Goergen, F. & Bergmann, KC. The pollator: a personal pollen sampling device. Allergo J Int (2018) 27: 1. doi.org/10.1007/s40629-017-0034-y

• Karatzas K, Riga M, Berger U, Werchan M, Pfaar O, Bergmann KC. Computational validation of the recently proposed pollen season definition criteria. Allergy (2018) ;73(1):5-7. doi:10.1111/all.13255.