[Ragweed pollen (Ambrosia artemisiifolia L.): prediction and prevention].

Ragweed is the dominant type of the atmospheric spora of North America. In this paper we present a forecasting model based on the probabilistic distribution of pollen curves, which was applied to four years of sampling. Except for rapid (24 hours) but large fluctuations of the pollen concentration, our algorithm allows for an adequate estimate of the exposure risk. However, these rapid fluctuations can account for up to 40% of the annual pollen sum.