Allergènes «outdoor» Pollen, spores et changements climatiques

Transcription

1 Département fédéral de l intérieur DFI Office fédéral de météorologie et de climatologie MétéoSuisse Allergènes «outdoor» Pollen, spores et changements climatiques Bernard Clot Aérobiologie et allergies respiratoires, CHUV,

2 Switzerland Winter

3 Switzerland Lausanne 3

4 Switzerland

5 MeteoSwiss pollen monitoring network 5

6 New pollen calendars climat phénologie et pollen 6

7 News from pollen monitoring 7

8 News from pollen modelling 8

9 Outline Introduction : factors affecting airborne concentrations ( exposure) Observed and expected changes and possible causes Spores Pollen or allergen? Conclusions 9

10 Main factors affecting airborne pollen/spores concentrations Sources distribution and density (plant, fungus) Internal factors: species, variety, genotype Environmental factors (soil, competition, pathogens, pollution, etc.) Natural vegetation // Managed environment (agriculture, cities, etc.) Weather before and during the flowering / pollen season Mainly responsible for inter-annual variability Timing of the season (start, peak, end), pollen production (potential) Pollen release in the air, dispersion and transport, deposition 10

11 Importance of the regional vegetation (Annual pollen c. sum) Low altitude plant: ash Indice annuel moyen frêne BS CDF Mo Wi Da Sa Gü Alpine plant: green alder Indice annuel moyen aune vert BS CDF Mo Wi Da Sa Gü Basel CDF Montana Wiesen Davos Samedan Gütsch 280m 1040m 1350m 1420m 1600m 1700m 2290m Indice annuel moyen armoise Local vegetation: mugwort BS CDF Mo Wi Da Sa Gü 11

12 Annual variations: influence of weather Example: different birch pollen seasons in Neuchâtel mars 21-mars 10-avr 30-avr 20-mai 12

13 Climate warming 13

14 Outline Introduction : factors affecting airborne concentrations ( exposure) Observed and expected changes and possible causes Spores Pollen or allergen? Conclusions 14

15 Effects of climate change on airborne pollen (exposure): the general picture Change in the timing of the pollen seasons Earlier start / peak Longer pollen season Change in pollen amount More pollen (climate warming, increase of CO 2, ) Change in pollen quality Increasing amounts of allergens & inflammatory molecules Change in pollen spectrum (vegetation shift) Exposure to a larger number of allergens or new allergens 15

16 Besancenot & Thibaudon 2012 Changement climatique et pollinisation Revue des Maladies Respiratoires 29, % of 64 publications reviewed Longer season No change Shorter season Winter, trees Spring, trees Herbs

17 Ziello et al Changes to Airborne Pollen Counts across Europe (97 stations). PLoS ONE 7(4) 17

18 Annual pollen concentrations sum 18

19 Annual pollen concentrations sum 19

20 Annual pollen concentrations sum 20

21 Annual pollen concentrations sum 21

22 Annual pollen concentrations sum 22

23 Annual pollen concentrations sum 23

24 Annual pollen concentrations sum 24

25 Ragweed in Ticino 25

26 Ziello et al Changes to Airborne Pollen Counts across Europe. PLoS ONE 7(4) No signal with T change, but with urbanization 22 % significant trends Most time series are short (83% <20 years, 3% >25years) 26

27 Outline Introduction : factors affecting airborne concentrations ( exposure) Observed and expected changes and possible causes Spores Pollen or allergen? Conclusions 27

28 Spores Climate warming increased biomass saprophytic activity Changes in humidity! Similar influence of weather Wet weather spores Dry weather spores Influence of the environment and human activities Local climate, vegetation, managment Role in thunderstorm asthma 28

29 Spores trends Alternaria in Derby, UK ( ) Strong increase in spores concentrations Earlier start date [Corden & Millington, 2001, Aerobiologia] Thessaloniki ( ), 14 taxa Decrase in spores concentrations Later start date, shorter season [Damialis et al., 2015, Fungal Ecology] Bratislava ( ) Earlier start date, later end date and longer duration of Alternaria Higher Stemphylium concentrations [Scevkova et al., 2016, Aerobiologia] 29

30 Spores trends Catalunia SP ( ) 12/14 increasing trends in spores concentrations Decreasing Drechslera-Helminthosporium and Curvularia [Velez-Pereira et al, 2016, Aerobiologia] Poznan PL ( ), Leptoshaeria Warmer, more rain Increasing amounts, longer season [Kaczmarek et al., 2016, Aerobiologia] Cladosporium in France ( ) Increasing in the North Decreasing in the South [Sindt et al., 2016, Aerobiologia] 30

31 Outline Introduction : factors affecting airborne concentrations ( exposure) Observed and expected changes and possible causes Spores Pollen or allergen? Conclusions 31

32 Buters et al. Atmospheric Environement 2012 Release of Bet v 1 from birch pollen from 5 European countries Birch: 10 x difference in potency (allergen release / pollen grain) 32

33 Galan et al. Allergy 2013 Airborne olive pollen counts are not representative of exposure to the major olive allergen Ole e 1 12 x difference in potency (allergen release / pollen grain) 33

34 Buters et al. JACI 2015 Variation of the group 5 grass pollen allergen content of airborne pollen in relation to geographic location and time in season Grass: allergens in the small fraction 34

35 De Weger et al., Clin. Translat. Allergy 2011, 1:18 Difference in symptom severity between early and late grass pollen season in patients with seasonal allergic rhinitis. 35

36 Outline Introduction : factors affecting airborne concentrations ( exposure) Observed and expected changes and possible causes Spores Pollen or allergen? Conclusions 36

37 Conclusion Climate change increases the risk of allergy by increasing the diversity of allergens, the duration of season and airborne concentrations, and also increases indirect risk factors such as air pollution Not only weather and climate, but above all human activities are the most important factors influencing local exposure With regard to allergy, it is possible to take action in order to favour a safer environment, in particular at local/regional scale It is important to inform the decision-makers about the possible actions to limit the exposure to allergens 37

38 It is possible to have a management of our environment that consider the allergens producing plants invasives weeds 38

39 It is possible to better choose the trees we plant Indigenous Exotics Cultivars 39

40 Thank you for your attention! Questions?