"At the moment there is nothing to fear. It's far too cold. The trees have neither pollen nor leaves. But as soon as it gets warmer it could go pretty fast with the allergenic early-flowerers. One should expect that they practically explode," warned Professor Andreas Dietz, director of the ears, nose and throat clinic of Leipzig University Hospital.
"The pollen will be kept under wraps for a relatively long time by the cold. It was not warm and then cold again, which would have frozen the first blossoming activity. Thus one should expect that things start happening relatively rapidly."
He said birch, which blossoms early, was a classic allergen, and that his team expects the first hay fever patients to show up as soon as the weather warms up.
Another nightmare for hay fever sufferers due to what is described as its aggressive pollen, is common ragweed, a plant originating in North America, but which is spreading through Germany. The Frankfurter Rundschau reported on Tuesday that a new study showed the plant was profiting from climate change and was likely to colonise new areas.
Factors which benefit the plant include contaminated seeds and bird food from southern Europe, as well as the extended vegetation period and increased average temperatures caused by global warming.
Around 12 percent of Germans are allergic to the plant's pollen, the paper said.