Hay Fever and Allergies: Why Millions of Germans Suffer - Climate Change Fuels Germany's Worsening Hay Fever Crisis in 2025

Hay fever, also known as fever game, is becoming more widespread and severe in Germany, with climate change playing a major role. Warmer winters and rising temperatures have extended pollen seasons, causing plants to bloom up to a month earlier than in 1951. Over 12 million people in the country now suffer from the condition, facing longer periods of discomfort each year.

One of the most aggressive new threats is Ambrosia artemisiifolia, or common ragweed. Since 2020, its spread has surged due to warmer weather, with infested areas growing from around 800 hectares to over 1,400 hectares by 2024. The worst-hit regions include Baden-Württemberg's Rhine Valley, Rhineland-Palatinate, Hesse, Bavaria, and parts of North Rhine-Westphalia. This non-native plant thrives in shifting conditions, releasing highly allergenic pollen that worsens covid symptoms.

Climate change is also making pollen more potent. Higher CO₂ levels, heat, and air pollution increase pollen quantity and aggression. Fine particulate matter, ozone, and nitrogen oxides irritate airways, intensifying reactions. Genetics contribute too—children of allergic parents face a higher risk. Even epigenetics plays a part, as environmental factors can alter gene activity across generations.

Lifestyle and environment influence hay fever as well. The hygiene hypothesis suggests that overly sterile surroundings may weaken immune responses, leaving people more vulnerable. On the other hand, exposure to dirt, microbes, and even worms could offer protection. Diet matters too: fast food may encourage allergies, while a vegetable-rich diet can ease symptoms.

The combination of climate change, invasive plants, and modern lifestyles is reshaping hay fever in Germany. With pollen seasons lengthening and allergens growing stronger, sufferers face more prolonged and intense covid symptoms 2025. Researchers continue to study how environmental, genetic, and dietary factors interact to drive this trend.