Influence of meteorological variables and air pollutants on measurements from automatic pollen sampling devices.

This study examines the influence of meteorological factors and air pollutants on the performance of automatic pollen monitoring devices, as part of the EUMETNET Autopollen COST ADOPT-intercomparison campaign held in Munich, Germany, during the 2021 pollen season. The campaign offered a unique opportunity to compare all automatic monitors available at the time, a Plair Rapid-E, a Hund-Wetzlar BAA500, an OPC Alphasense, a KH-3000 Yamatronics, three Swisens Polenos, a PollenSense APS, a FLIR IBAC2, a DMT WIBS-5, an Aerotape Sextant, to the average of four manual Hirst traps, under the same environmental conditions. The investigation aimed to elucidate how meteorological factors and air pollution impact particle capture and identification efficiency. The analysis showed coherent results for most devices regarding the correlation between environmental conditions and pollen concentrations. This reflects on one hand, a significant correlation between weather and airborne pollen concentration, and on the other hand the capability of devices to provide meaningful data under the conditions under which measurements were taken. However, correlation strength varied among devices, reflecting differences in design, algorithms, or sensors used. Additionally, it was observed that different algorithms applied to the same dataset resulted in different concentration outputs, highlighting the role of algorithm design in these systems (monitor + algorithm). Notably, no significant influence from air pollutants on the pollen concentrations was observed, suggesting that any potential difference in effect on the systems might require higher air pollution concentrations or more complex interactions. However, results from some monitors were affected to a minor degree by specific weather variables. Our findings suggest that the application of real-time devices in urban environments should focus on the associated algorithm that classifies pollen taxa. The impact of air pollution, although not to be excluded, is of secondary concern as long as the pollution levels are similar to a large European city like Munich.

Spatial and temporal variations in airborne Ambrosia pollen in Europe.

The European Commission Cooperation in Science and Technology (COST) Action FA1203 "SMARTER" aims to make recommendations for the sustainable management of Ambrosia across Europe and for monitoring its efficiency and cost-effectiveness. The goal of the present study is to provide a baseline for spatial and temporal variations in airborne Ambrosia pollen in Europe that can be used for the management and evaluation of this noxious plant. The study covers the full range of Ambrosia artemisiifolia L. distribution over Europe (39°N-60°N; 2°W-45°E). Airborne Ambrosia pollen data for the principal flowering period of Ambrosia (August-September) recorded during a 10-year period (2004-2013) were obtained from 242 monitoring sites. The mean sum of daily average airborne Ambrosia pollen and the number of days that Ambrosia pollen was recorded in the air were analysed. The mean and standard deviation (SD) were calculated regardless of the number of years included in the study period, while trends are based on those time series with 8 or more years of data. Trends were considered significant at p < 0.05. There were few significant trends in the magnitude and frequency of atmospheric Ambrosia pollen (only 8% for the mean sum of daily average Ambrosia pollen concentrations and 14% for the mean number of days Ambrosia pollen were recorded in the air). The direction of any trends varied locally and reflected changes in sources of the pollen, either in size or in distance from the monitoring station. Pollen monitoring is important for providing an early warning of the expansion of this invasive and noxious plant.

Defining pollen exposure times for clinical trials of allergen immunotherapy for pollen-induced rhinoconjunctivitis - an EAACI position paper.

BACKGROUND: Clinical efficacy of pollen allergen immunotherapy (AIT) has been broadly documented in randomized controlled trials. The underlying clinical endpoints are analysed in seasonal time periods predefined based on the background pollen concentration. However, any validated or generally accepted definition from academia or regulatory authorities for this relevant pollen exposure intensity or period of time (season) is currently not available. Therefore, this Task Force initiative of the European Academy of Allergy and Clinical Immunology (EAACI) aimed to propose definitions based on expert consensus. METHODS: A Task Force of the Immunotherapy and Aerobiology and Pollution Interest Groups of the EAACI reviewed the literature on pollen exposure in the context of defining relevant time intervals for evaluation of efficacy in AIT trials. Underlying principles in measuring pollen exposure and associated methodological problems and limitations were considered to achieve a consensus. RESULTS: The Task Force achieved a comprehensive position in defining pollen exposure times for different pollen types. Definitions are presented for 'pollen season', 'high pollen season' (or 'peak pollen period') and 'high pollen days'. CONCLUSION: This EAACI position paper provides definitions of pollen exposures for different pollen types for use in AIT trials. Their validity as standards remains to be tested in future studies.

Short-term effects of airborne ragweed pollen on clinical symptoms of hay fever in a panel of 30 patients.

OBJECTIVES: Ragweed, Ambrosia artemisiifolia, is a highly allergenic annual herbaceous plant that is spreading quickly across the globe. Few studies have investigated the relationship between ragweed pollen counts and hay fever symptoms. We investigate the dose-response relationship between ragweed exposure in patients sensitized to ragweed and daily hay fever symptoms. METHOD: A panel study was conducted among 31 adult patients sensitized to A artemisiifolia in France and Switzerland. Rhinitis, conjunctivitis, and bronchial symptoms were recorded daily, as well as daily pollen counts of ragweed, air pollutants, and meteorological data over 2 successive years. Data were analyzed with generalized estimating equation models to quantify effects of ragweed pollen whilst controlling for confounders. RESULTS: The relationship between ragweed pollen and the percentage of patients with nasal, ocular, and bronchial symptoms was linear. For every increase of 10 grains/m3, the odds ratio (OR) (95% confidence interval) for nasal symptoms was, in 2009, 1.18 [1.04-1.35] on weekdays and 1.43 [1.16-1.75] at weekends, and in 2010, 1.04 [1.00-1.07] on weekdays and 1.25 [1.06-1.46] at weekends.The OR for ocular symptoms was 1.32 [1.16-1.56] in 2009 and 1.05 [1.02-1.07] in 2010. Finally, the OR for bronchial symptoms was 1.14 [1.03-1.25] in 2009 and 1.03 [0.97-1.08] in 2010. CONCLUSION: There is a statistically significant linear relationship between ragweed pollen counts and hay fever symptoms. Our study shows that nasal symptoms differ on weekdays and at weekends.

Short-term effects of airborne ragweed pollen on clinical symptoms of hay fever in a panel of 30 patients

Objectives: Ragweed, Ambrosia artemisiifolia , is a highly allergenic annual herbaceous plant that is spreading quickly across the globe. Few studies have investigated the relationship between ragweed pollen counts and hay fever symptoms. We investigate the dose-response relationship between ragweed exposure in patients sensitized to ragweed and daily hay fever symptoms. Method: A panel study was conducted among 31 adult patients sensitized to A artemisiifolia in France and Switzerland. Rhinitis, conjunctivitis, and bronchial symptoms were recorded daily, as well as daily pollen counts of ragweed, air pollutants, and meteorological data over 2 successive years. Data were analyzed with generalized estimating equation models to quantify effects of ragweed pollen whilst controlling for confounders. Results: The relationship between ragweed pollen and the percentage of patients with nasal, ocular, and bronchial symptoms was linear. For every increase of 10 grains/m 3 , the odds ratio (OR) (95% confidence interval) for nasal symptoms was, in 2009, 1.18 [1.04-1.35] on weekdays and 1.43 [1.16-1.75] at weekends, and in 2010, 1.04 [1.00-1.07] on weekdays and 1.25 [1.06-1.46] at weekends. The OR for ocular symptoms was 1.32 [1.16-1.56] in 2009 and 1.05 [1.02-1.07] in 2010. Finally, the OR for bronchial symptoms was 1.14 [1.03- 1.25] in 2009 and 1.03 [0.97-1.08] in 2010. Conclusion: There is a statistically significant linear relationship between ragweed pollen counts and hay fever symptoms. Our study shows that nasal symptoms differ on weekdays and at weekends (AU)

Objetivos: La Ambrosia artemisiifolia es una planta herbácea, altamente alergénica, que tiende a extenderse mundialmente muy rápidamente. Muy pocos estudios han investigado la relación de los contajes de polen de ambrosia con la intensidad de los síntomas. En este trabajo hemos documentado la relación dosis/respuesta entre la exposición a ambrosia, en pacientes sensibilizados a este polen, y la intensidad de su sintomatología Métodos: En el estudio se incluyeron 31 pacientes residentes en Francia o Suiza y sensibilizados a Ambrosia artemisiifolia . Durante dos años consecutivos, se registraron diariamente los síntomas oculares, nasales y bronquiales de los pacientes, los niveles de polen de ambrosía, los niveles de contaminantes ambientales junto con los datos. El análisis de los datos se realizó mediante la construcción de modelos de ecuaciones de estimación generalizada, de forma que se pudiera cuantificar los efectos del polen de ambrosia y controlando las variables de confusión. Resultados: La relación entre los recuentos de polen de ambrosía y el porcentaje de pacientes con síntomas nasales, oculares y bronquiales fue linear. Para cada incremento de 10 granos/m 3 , el OR para los síntomas nasales, en el año 2009, fue 1.18 [1.04-1.35] durante los días entre semana, y 1.43 [1.16-1.75] durante el fin de semana, y en 2010, 1.04 [1.00-1.07] durante los días entre semana y 1.25 [1.06-1.46] durante el fin de semana; el OR para los síntomas oculares fue de 1.32 [1.16-1.56] en el 2009 y 1.05 [1.02-1.07] en el 2010; el OR para los síntomas bronquiales fue 1.14 [1.03-1.25] en 2009 y 1.03 [0.97-1.08] en 2010. Conclusión: Hemos demostrado una relación lineal significativa entre los recuentos de polen de ambrosía y los síntomas de la polinosis en los pacientes sensibilizados. Nuestro estudio también demostró que el nivel de molestias difiere entre los días entre semana comparados con los del fin de semana (AU)

A method to derive vegetation distribution maps for pollen dispersion models using birch as an example.

Detailed knowledge of the spatial distribution of sources is a crucial prerequisite for the application of pollen dispersion models such as, for example, COSMO-ART (COnsortium for Small-scale MOdeling-Aerosols and Reactive Trace gases). However, this input is not available for the allergy-relevant species such as hazel, alder, birch, grass or ragweed. Hence, plant distribution datasets need to be derived from suitable sources. We present an approach to produce such a dataset from existing sources using birch as an example. The basic idea is to construct a birch dataset using a region with good data coverage for calibration and then to extrapolate this relationship to a larger area by using land use classes. We use the Swiss forest inventory (1 km resolution) in combination with a 74-category land use dataset that covers the non-forested areas of Switzerland as well (resolution 100 m). Then we assign birch density categories of 0%, 0.1%, 0.5% and 2.5% to each of the 74 land use categories. The combination of this derived dataset with the birch distribution from the forest inventory yields a fairly accurate birch distribution encompassing entire Switzerland. The land use categories of the Global Land Cover 2000 (GLC2000; Global Land Cover 2000 database, 2003, European Commission, Joint Research Centre; resolution 1 km) are then calibrated with the Swiss dataset in order to derive a Europe-wide birch distribution dataset and aggregated onto the 7 km COSMO-ART grid. This procedure thus assumes that a certain GLC2000 land use category has the same birch density wherever it may occur in Europe. In order to reduce the strict application of this crucial assumption, the birch density distribution as obtained from the previous steps is weighted using the mean Seasonal Pollen Index (SPI; yearly sums of daily pollen concentrations). For future improvement, region-specific birch densities for the GLC2000 categories could be integrated into the mapping procedure.

Ragweed (Ambrosia) progression and its health risks: will Switzerland resist this invasion?

The purpose of this article is to alert physicians for the environmental and health threats of Ambrosia artemisiifolia (common ragweed) in Switzerland. Switzerland borders several heavily ragweed colonised areas. Up to 12% of the population suffers from allergies (hay fever, asthma) to ragweed pollen in these areas. Switzerland is beginning to be invaded by this plant. Currently, the ragweed pollen counts are still low but can reach local peaks that induce symptoms in allergic individuals. Ragweed allergy, however, is still rare in Switzerland. Because the amount of ragweed pollen was increasing in the last few years, identification and surveillance of ragweed plant foci was started. Colonisation is currently systematically monitored in Geneva and southern Tessin. Major accumulation of ragweed foci have been detected in the canton of Geneva, the western shore of the lake of Geneva belonging to the canton of Vaud, and in the southern part of the canton of Tessin, aside from minor foci registered all over Switzerland. The routes of ragweed invasion are presented and discussed. Current measures of ragweed containment and needs for the future are presented. The urge for these measures at an early stage of ragweed spread is underlined by the impracticability of eradication in highly colonised areas. The costs of preventing ragweed spread in Switzerland are likely to be several magnitudes lower than the treatment of a significant percentage of the Swiss population for ragweed pollen allergy. Because areas can change from low to heavy ragweed colonisation within a few years, the current window of opportunity to prevent further colonisation by ragweed should not be missed.

Empowering humanitarian medical development using grid technology.

BACKGROUND: The training of local clinicians is the best way to raise the standard of medical knowledge in developing countries. This requires transferring skills, techniques and resources. OBJECTIVES: Grid technology opens new perspectives for preparation and follow-up of medical missions in developing countries as well as support to local medical centers in terms of teleconsulting, telediagnosis and patient follow-up. Indeed, grids allow to hide the complexity of handling distributed data in such a way that physicians will be able to access patient data while ignoring where these data are stored. METHODS: To meet requirements of a development project of the French NPO Chain of Hope in China, we propose to deploy a grid-based federation of databases. FIRST RESULTS AND CONCLUSIONS: A first protocol was established for describing the patients' pathologies and their pre- and post-surgery states through a web interface in a language-independent way. This protocol was evaluated by French and Chinese clinicians during medical missions in the fall of 2003. The first sets of medical patients recorded in the databases will be used to evaluate grid implementation of services.

[Ambrosia pollen in Switzerland--produced locally or transported?]. / Pollen d'ambroisie en Suisse: production locale ou transport?

The ambrosia (Ambrosia artemisiifolia L.) has been announced in Switzerland for more than 100 years. During the last decade, signs of an increased presence of the ambrosia and its pollen appear in the south-west of Switzerland, in particular in Geneva. Aerobiologic measurements make it possible to highlight the importance of the transport of pollen by the winds since the area of Lyon, where the ambrosia is abundant. It also bring elements making it possible to detect a local production of pollen in the Geneva area, where several invaded fields were discovered with the autumn 2001. A multidisciplinary group was created in Geneva and it attempts to prevent as far as possible probable invasion of the ambrosia.

Phytophenological trends in Switzerland.

Nation-wide phenological observations have been made in Switzerland since 1951. In addition to these observation programmes, there are two very long phenological series in Switzerland: leaf bud burst of horse-chestnut trees has been observed in Geneva since 1808 and full flowering of cherry trees in Liestal since 1894. In addition to the presentation of these two long phenological series, trends for 896 phenological time series have been calculated with national data from 1951 to 1998. The earlier bud burst of horse-chestnut trees in Geneva can be attributed mainly to the city effect (warmth island). This phenomenon was not observed with the cherry tree flowering in Liestal. A clear trend towards earlier appearance dates in spring and a weak tendency towards later appearance dates in autumn could be shown with data from the national observation network. It must be noted that different phenophases and plant species react differently to various environmental influences.