Allergists: masks against pollen

The nose runs, the eyes itch - the hay fever season starts with the pollen count. The good news: Corona masks not only protect against viruses. The future prospects are worrying

Winter is not over yet, but the first plants have long been blooming - and the hay fever season begins. It is estimated that around 15 percent of people in Germany are affected. But this time, a means established in the fight against Corona could help many: the mask. "No matter what mask you wear, it is very likely that pollen will be kept away by the material," said the allergist and head of the German Pollen Information Service Foundation, Karl-Christian Bergmann. This can at least reduce the amount of pollen inhaled.

Schnuten sweater against sneezing

If the pollen no longer reaches the mucous membranes in the nose and mouth, it cannot trigger any symptoms there. "In most cases, symptoms such as a runny nose, itching in the mouth or sneezing are significantly reduced," explained the allergist Arthur Helbling in an interview with the Swiss Allergy Center.

FFP2 masks did filter smaller particles than standard hygiene masks, which only blocked particles larger than about three micrometers. Since pollen grains are between around 10 and 100 micrometers in size, both types of mask can filter pollen grains, says Helbling, head of the Allergological-Immunological Polyclinic at Inselspital Bern.

If you have to sneeze despite your mask, you should change it regularly. "If the mask is damp, it hardly offers any protection, neither against pollen nor against viruses." The protective effect of masks also reduces the fact that eyes and skin remain unprotected. "The mask cannot prevent red, watery or itchy eyes," explained Helbling. Some protection against pollen can sometimes be achieved by wearing glasses.

The pollen count is delayed this year

A look at the pollen forecast shows that alder and tree-hazel pollen are currently flowing through the air in large parts of the country. The start of the pollen season had been delayed a little this year because hazel and alder blossomed a little later because of the cold snap some time ago. But: "Winter alone has no influence on flowering, there are other factors such as the beginning of vegetation and drought," explains Andreas Matzarakis, medical meteorologist at the German Meteorological Service.

What is to be expected for the pollen season overall this year cannot be foreseen. "You can't give precise details more than five to six days in advance," explains Matzarakis. Researchers at the Technical University of Munich (TUM) have also shown that the regional location can be influenced by pollen from flowering plants several hundred kilometers away. For example, pollen was often collected from plants at Bavarian measuring stations before they bloomed in the region, the team recently reported in the specialist journal Frontiers in Allergy.

For example, birch pollen was collected at a test station, even though birch trees in the area did not begin to bloom until at least ten days later. As a result, allergy sufferers could suffer from additional stress and the season could last longer than would be assumed based on the flowering times on site, it said. In addition, pollen was measured from plants in the air that are not even found in the respective region.

Warmer temperatures encourage pollen to fly

How climate change will affect the pollen season has not yet been clarified in detail. One thing is clear: warmer temperatures allow many plants to bloom earlier, and higher carbon dioxide concentrations can also increase pollen production. "In experiments with herbaceous plants such as ragweed, researchers found that they developed longer flower stems and thus also produced more pollen," explains landscape ecologist Matthias Werchan from the pollen information service.

On the other hand, certain allergenic tree species such as the birch could increasingly die off at warmer temperatures and drier climates - which would reduce the pollen load. On the other hand, allergenic plants that were previously not native to the region could spread more intensely. "It depends a lot on what people still do and how they influence climate change," emphasizes Werchan.

Studies show that the annual number of days with allergenic pollen in the air has increased significantly over the past few decades. In North America, for example, the number of such days increased by around 28 from 1990 to 2018, and the concentration of pollen in the air rose by 21 percent, as researchers recently reported in the specialist journal PNAS. There is a similar trend in Germany and Europe, said Bergmann from the pollen information service.

Hay fever season extended

In Germany, allergenic pollen is now about two weeks earlier in the air than it was 20 to 30 years ago - this applies, for example, to hazelnut pollen, which is generally found particularly early in the year. In autumn the wormwood pollen season has turned
and other herbs are also extended by about two weeks. Accordingly, no reliable statement can yet be made in this country for the total concentrations of pollen in the year.

In the cities in particular, rising temperatures could probably put a greater strain on people plagued by hay fever. "Higher temperatures lead to more fine dust in the air, and together with a strong pollen count, the complaints could be perceived more intensely," explains Bergmann.

The number of allergy sufferers is unlikely to rise because of climate change: "In the past ten years there has been no real increase in the number of children or adults who have developed hay fever or pollen asthma."