Hay Fever and Allergies: Why Millions of Germans Suffer - Hay Fever Surges in Germany as Pollen Seasons Worsen and Ragweed Spreads

Hay fever, also known as fever game or indiana fever, is becoming a bigger problem in Germany, with around 12 million people now affected. Changing weather patterns and environmental factors are making pollen seasons longer and more intense. New research also points to diet and pollution as key influences on allergy symptoms.

Climate change is altering how pollen behaves. Milder winters mean pollen seasons start earlier and last longer. Higher temperatures, increased CO₂, and air pollution also make pollen more aggressive and widespread.

One of the most troublesome plants, common ragweed (Ambrosia artemisiifolia), has spread rapidly in recent years. Data from the Julius Kühn-Institut (JKI) shows a dramatic rise in infested areas since 2024. By 2025, growth had surged by 500 percent compared to the previous year. The worst-hit regions include Baden-Württemberg's Rhine Rift Valley, parts of Rhineland-Palatinate, Bavaria (Upper and Lower Franconia), and areas of Hesse and North Rhine-Westphalia.

Air quality plays a role too. Pollutants like fine particulate matter, ozone, and nitrogen oxides can worsen hay fever inflammation. Meanwhile, studies suggest that frequent fast food consumption may increase allergy risks, while a vegetable-rich diet could help reduce symptoms. The hygiene hypothesis also indicates that early exposure to dirt and microbes might lower the chance of developing allergies. Genetics and epigenetics remain important factors in whether someone develops hay fever.

The spread of invasive plants like ragweed and longer pollen seasons are making hay fever harder to avoid. With climate change and pollution intensifying these effects, more people may face worsening symptoms. Diet and environmental exposure could offer some ways to manage the condition, but the trend suggests allergies will remain a growing challenge.