The Long Distance Transport of Airborne Ambrosia Pollen to the UK and the Netherlands from Central and South Europe

Background: The invasive alien species Ambrosia artemisiifolia (common or short ragweed) is increasing its range in Europe. In the UK and the Netherlands airborne concentrations of Ambrosia pollen are usually low. However, more than 30 Ambrosia pollen grains per cubic metre of air (above the level capable to trigger allergic symptoms) were recorded in Leicester (UK) and Leiden (NL) on 4 and 5 September 2014. Objective: The aims of this study were to determine whether the highly allergenic Ambrosia pollen recorded during the episode could be the result of long distance transport, to identify the potential sources of these pollen grains and describe the conditions that facilitated this possible long distance transport. Methods: Airborne Ambrosia pollen data were collected at 10 sites in Europe. Back trajectory and atmospheric dispersion calculations were performed using HYSPLIT_4. Results: Back trajectories calculated at Leicester and Leiden show that higher altitude air masses (1500m) originated from source areas on the Pannonian Plain and Ukraine. During the episode, air masses veered to the west and passed over the Rhône Valley. Dispersion calculations showed that the atmospheric conditions were suitable for Ambrosia pollen released from the Pannonian Plain and the Rhône Valley to reach the higher levels and enter the air stream moving to Northwest Europe where they were deposited at ground level and recorded by monitoring sites. Conclusions: The study indicates that the Ambrosia pollen grains recorded during the episode in Leicester and Leiden were probably not produced by local sources, but transported long distances from potential source regions in East Europe, i.e. the Pannonian Plain and Ukraine, as well as the Rhône Valley in France.

Temporal and Georaphical Variations in Grass Pollen Seasons in Areas of Western Europe: an Analysis of Season dates at Sites of the European Pollen Information System.

Geographical and temporal variations in the start dates of grass pollen seasons are described for selected sites of the European Pollen Information Service. Daily average grass pollen counts are derived from Network sites in Finland, the Netherlands, Denmark, United Kingdom, Austria, Italy and Spain, giving a broad longitudinal transect over Western Europe. The study is part of a larger project that also examines annual and regional variations in the severity, timing of the peak and duration of the grass pollen seasons. For several sites, data are available for over twenty years enabling long term trends to be discerned. The analyses show notable contrasts in the progression of the seasons annually with differing lag times occurring between southern and northern sites in various years depending on the weather conditions. The patterns identified provide some insight into geographical differences and temporal trends in the incidence of pollinosis. The paper discusses the main difficulties involved in this type of analysis and notes possibilities for using data from the European Pollen Information service to construct pan European predictive models for pollen seasons.

The Influence of Borderline Personality Traits on the Course of Bipolar Disorder

Background and Aims: Bipolar disorder and borderline personality disorder are commonly comorbid. Borderline personality disorder is diagnosed categorically, but personality pathology may be better characterised dimensionally. The impact of borderline personality traits (not diagnosis) on the course of bipolar disorder is unknown. We examined the presence and severity of borderline personality traits in a large UK sample of bipolar disorder, and the impact of these traits on illness course. Methods: Borderline Evaluation of Severity over Time (BEST) was used to measure presence and severity of borderline traits in 1447 individuals with DSM-IV bipolar I disorder (n = 1008) and bipolar II disorder (n = 439) recruited into the Bipolar Disorder Research Network (www.bdrn.org). Clinical course was measured via semi-structured interview (Schedules for Clinical Assessment in Neuropsychiatry) and case-notes. Results: BEST score was higher in bipolar II than bipolar I (36 v 27, p < 0.001) and 9/12 individual BEST traits were significantly more common in bipolar II than bipolar I. Within both bipolar I and bipolar II higher BEST score was associated with younger age of bipolar onset (p < 0.001), history of alcohol misuse (p < 0.010), and history of suicide attempt (p < 0.001). Conclusions: Borderline personality traits are common in bipolar disorder, and more severe in bipolar II than bipolar I disorder. Borderline trait severity was associated with more severe bipolar illness course; younger age of onset, alcohol misuse and suicidal behaviour. Clinicians should be vigilant for borderline personality traits irrespective of whether criteria for diagnosis are met, particularly in those with bipolar II disorder and younger age of bipolar onset.