Hay Fever Season Extended by Two Weeks Due to Climate Change, Report Reveals
Hay fever sufferers in the UK are now enduring symptoms for up to two weeks longer than they would have in the 1990s, according to a comprehensive new review. The Lancet Countdown in Europe 2026 report attributes this extension directly to climate change, which has "prolonged the pollen season" and increased the duration of allergen exposure for millions of people.
Climate Change Shifts Pollen Seasons
Published in The Lancet Public Health, the report details how climate change is altering the flowering seasons of plants that release allergenic pollen. Researchers examined changes in the timing and intensity of birch, alder, and olive pollen seasons, finding that the season start for all allergenic trees has shifted earlier by one to two weeks between 2015 and 2024 compared to the period from 1991 to 2000.
"Climate change has prolonged the pollen season by one to two weeks, increasing the duration of exposure for people with allergic rhinitis," the authors stated. Hay fever occurs when individuals are allergic to pollen from trees, grass, and weeds, with symptoms typically worsening during warm, humid, and windy weather when pollen counts peak, usually from late March to September.
Impact on Public Health and NHS Resources
Anne Biggs, deputy head of clinical services at Allergy UK, commented on the findings, noting that hay fever affects millions annually in the UK. "While for some their symptoms can be mild, for many their hay fever symptoms impact their quality of life," she said. Biggs emphasized that research into pollen season timing and length is crucial for optimizing treatment and management of allergic conditions.
Dr. Samantha Walker, director of research and innovation at Asthma and Lung UK, warned that a longer pollen season will bring more misery for hay fever sufferers. "We know from a recent survey that nearly half of people with asthma and more than a quarter of those surveyed with COPD experience symptoms triggered by pollen," she explained. Pollen allergies can inflame airways, leading to life-threatening asthma attacks and COPD flare-ups.
A separate allergy strategy, supported by charities, patients, and doctors, highlights that the UK has some of the highest allergy rates globally, with 39% of children and 30% of adults affected. It warns that NHS care and treatment for allergies are "dramatically under-resourced," exacerbating the challenges posed by extended pollen seasons.
Broader Climate Change Health Risks in Europe
The report, authored by 65 researchers from 46 academic and UN institutions, also addresses wider climate-related health risks in Europe. Heat health warnings have increased by 318% compared to the 1990s, with nearly all monitored regions experiencing more heat-attributable deaths between 2015 and 2024 than from 1991 to 2000. In 2024 alone, an estimated 62,000 deaths in Europe were attributed to heat.
Additionally, climate change is facilitating the spread of mosquito-borne viruses like dengue, with outbreak risks rising by 297% across Europe from 2015 to 2024 compared to 1981 to 2010. Professor Joacim Rocklov from the University of Heidelberg, co-director of the Lancet Countdown Europe, warned, "Across Europe, the health impacts of climate change are intensifying faster than our response is keeping up."
Calls for Action and Energy Transition
The authors stress that fossil fuel dependence worsens health risks, linking it to economic and public health vulnerabilities. Dr. Hannah Klauber from the Lancet Countdown Europe's economics and finance working group stated, "Accelerating the transition to clean, secure energy is not only an environmental necessity, but a vital opportunity to safeguard people's wellbeing." The report underscores that current choices will determine whether health impacts escalate or if Europe moves toward a safer, fairer, and more resilient future.
