Birch pollen, the links to pollen food syndrome and offers key messages for HCPs

Hay fever season is upon us as tree pollen starts to be released into the air. Clinical Nurse Advisor Holly Shaw looks at birch pollen, the links to pollen food syndrome and offers key messages for HCPs.

Supporting patients with seasonal allergic rhinitis requires a combination of pharmacological interventions and practical guidance on pollen avoidance to help reduce exposure to pollen and manage symptoms.  

  • 25% of adults in the UK are affected by allergic rhinitis (commonly known as Hay fever) 
  • 10-15% of the children in the UK are affected by allergic rhinitis 

Five takeaways about Birch tree pollen allergy 

  1. Birch pollen season usually peaks in sprin, between April and May. However, Birch pollen can cross-react with hazel and alder pollen, so some tree-pollen sufferers can experience symptoms starting in winter and lasting until June. 

Key message: Start conversations early and advise patients to start using allergy medications eg. nasal steroid sprays and non-sedating antihistamines two weeks before their symptoms would usually start.   

  1. Some people with Hay fever react to one type of pollen during the “season” and then feel better later in the year. It is also possible to be affected by more than one type of pollen or airborne allergen, leading to many months of allergic rhinitis symptoms; for example, some people have both tree pollen and grass pollen allergy and will experience symptoms for most of the spring and summer.

Key message: Education is key to ensure patients use their treatments consistently and not just when their symptoms are at their worst.  

  1. Birch trees produce pollen via yellow catkins that hang down from the branches. Like other tree pollens, the grains are incredibly small and pollinate by travelling on the wind.  Tree pollen can be carried long distances by even a light breeze – you do not need to be in direct contact with birch trees to experience symptoms.

Key Message: Advise patients to wear protection to keep pollen away from the eyes by wearing wraparound-style sunglasses and hats. Showering and a change of clothes after being outside helps remove pollen from the skin and hair and clothes. For more practical advice on pollen avoidance, signpost to the Allergy UK Hay Fever Factsheet.

  1. Birch trees have become very popular in streets and gardens in the UK. However, birch tree pollen is highly allergenic and if you have a choice, it is advisable to avoid planting birch trees near homes or in school grounds where the pollens can sensitise susceptible people, leading to worsening symptoms of allergy, including hay fever and asthma.

Key message: Signpost patients to check pollen count notifications to help plan daily activities. Avoiding exposure where possible when counts are high which include early mornings and early evenings. For more information, check out the resource section below. 

  1. Allergy testing isn’t usually needed for a hay fever diagnosis because the triggers are relatively easy to identify by taking a history of when and where symptoms occur. If the trigger isn’t obvious then skin prick tests or blood tests (specific IgE to the allergen to be tested) can be used.

The link between birch pollen and allergy to fruits and vegetables 

Birch pollen sensitivity can also cause pollen food syndrome (also called oral allergy syndrome). This is a hypersensitivity reaction to fruits, vegetables and nuts (often referred to as plant-based foods) usually causing mild irritant symptoms such as itching of the mouth, lips and throat when eaten in their raw form. 

If someone is susceptible to allergies, they can become sensitised to airborne pollens by breathing them in.  This is most associated with the classic symptoms of Hay fever including runny, itchy nose and itchy eyes. With food pollen syndrome many plant-based foods – fruit, vegetables, nuts and cereals have a protein structure that is very similar to the pollens in trees, grasses and weeds (this is called cross reactivity). However, the immune system doesn’t always recognise the difference between the pollens in the trees, grasses, or weeds that people breathe in and the pollen structure in the plant-based foods that they eat. With pollen food syndrome, the immune system recognises the food protein as an allergen and creates an allergic response. 

Some people are affected by only one or two foods and others can react to a wide range of foods. The most common foods involved are apples, peaches, kiwi, hazelnuts and almonds, but just about any fruit, vegetable or nut can cause a reaction. 

Allergy UK Factsheets can help support informed conversations between Health Care Professionals and promote self-management of conditions where relevant:   

The University of Worcester Pollen and Fungal Spore Forecast