Warning issued as Hay fever season set to be 2 weeks longer

Climate change has “prolonged the pollen season”, increasing the time people with hay fever are exposed to allergens, according to the Lancet Countdown in Europe 2026 report.

The study, published in The Lancet Public Health, found that flowering – and therefore pollen release – is shifting.

Researchers looked at birch, alder and olive and detected an earlier season start of one to two weeks for all allergenic trees between 2015 and 2024 compared with 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 said.

Commenting, Anne Biggs, deputy head of clinical services at Allergy UK, said: “Hay fever impacts millions of people in the UK each year.

“While for some their symptoms can be mild, for many their hay fever symptoms impact their quality of life.

“Research and understanding into the timing and length of the different pollen seasons is vital to support clinicians to ensure treatment and management of allergic conditions can be optimised.

“Details on longer pollen seasons is essential in the understanding and management of allergic conditions associated with pollens and air quality.

“It is an opportunity to raise awareness on not only the impact of hay fever, but the treatment options available to ensure people with pollen allergies can live symptom-free.”

A separate allergy strategy says the UK has some of the highest allergy rates in the world, with 39% of children and 30% of adults affected, but care is “dramatically under-resourced” in the NHS.

The broader climate and health report also flags rising heat‑related deaths, increased dengue risk and warns that “as long as Europe relies on fossil fuels our economies, our public budgets and ultimately our health will remain vulnerable”.

How many people in the UK could be affected by hay fever?

According to the BBC , “An estimated 13 million people in the UK suffer from hay fever,” with scientists at the University of Worcester predicting higher levels.

However, Jason Murphy, Head of Pharmacy at online pharmacy Chemist4U told Newsquest: the figure could be much higher.

“Tree, grass and weed pollen are the main triggers for hay fever, with tree pollen affecting around 25% of the population, the equivalent of 16.8 million people.

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“Typical symptoms can include repeated sneezing; a runny or blocked nose; itching in the nose, throat or ears; and watery, red, or itchy eyes.

“Tree pollen specifically can also trigger post-nasal drip, which leads to frequent throat clearing, coughing, and a hoarse voice.

“Those with asthma may also notice a tight chest, wheeze or shortness of breath, so it’s worth taking symptoms seriously when forecasts flag very high tree pollen levels.