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New method predicts the severity of the grass pollen season for allergy sufferers

Timothy grass. Photo
A lot og people are allergic to timothy grass. Photo: Whiteway/Istockphoto.

An international research team has found a new method for predicting entire pollen seasons, something that can help healthcare and allergy sufferers plan to reduce problems. No similar tool has previously been used in the area. The researchers also show that pollen seasons may be 60 per cent more severe in the future due to climate change.

For about one in four Swedes, the arrival of spring and summer means not only outdoor dining and birdsong, but also itchy eyes, a runny nose and tiredness, caused by high pollen levels in the air. To prevent or mitigate these allergic reactions there is a considerable need to be able to predict forthcoming pollen levels in the air, something that has only been possible to do from day to day. Until now.

Easier to plan

An international research team recently published an article in the research journal Science Advances in which they describe how they combined data from air temperature, precipitation and pollen concentrations from 28 monitoring stations in northwest Europe over several years to produce a model that can provide a forecast for an entire pollen season. They can even see how severe the forthcoming season is expected to be.

“The information makes it possible to plan further ahead, above all before the season has begun. For example, the forecasts can help healthcare staff to prepare for an increase in allergy-related illnesses. It also helps particularly sensitive individuals when they are to plan leave or stays abroad”, says researcher Georgina Brennan, Lund University, who worked on the study during her time at the Centre for Environmental and Climate Science (CEC) in Lund and is one of the authors of the article.  

The forecasts, which concern grass pollen, also make it possible to predict, for example, how much medication pharmacies need to stock in order to meet demand. In principle, the model can be introduced immediately. However, the researchers point out that it does not provide information on when a season starts or finishes, and it cannot predict the pollen level for a specific day.

A global health problem

Today, just over 40 per cent of Europe’s population is allergic to some type of pollen and it is considered to be a global health problem for 10-20 per cent of the world’s population. Many people are particularly sensitive to grass pollen, which is produced by orchard grass and timothy grass among others. In Sweden, grass pollen predominates from early summer to the autumn.

The researchers also produced a model which shows that climate change, with an increased carbon dioxide level in the atmosphere, will mean more severe pollen seasons in the future. According to the researchers, the pollen seasons will be 60 per cent more severe and more dangerous compared with today if the carbon dioxide level in the atmosphere doubles, in accordance with the UN climate panel’s “business-as-usual” scenario. This is because more carbon dioxide in the air increases the plants’ productivity and consequently their pollen production. This in turn leads to more allergic reactions.

“This is a serious problem that will affect many people’s lives”, says Georgina Brennan.

The study in Science Advances