For more information on diagnosis and management of allergic eye disease please see our Factsheet. Sam is nine years old and has been living with Vernal Keratoconjunctivitis a rare type of allergic eye disease. Sam also has asthma, and between the ages of one and four was admitted several times to hospital via the emergency department. Of all airborne allergens that we breathe in outdoors, pollens and mould spores are the most common and problematic. Typical hay fever symptoms are a runny nose, itchy and watery eyes, sneezing, and a feeling of nasal congestion.
Gardens can be designed to reduce exposure to allergens like pollen and moulds. The first principle of treating allergy is avoidance.
Total avoidance by staying indoors is not a realistic option, but reducing contact with allergens is possible, particularly where gardens are enclosed. Search website. What is hay fever? What causes hay fever? What are the symptoms? Poplar is a medium-sized deciduous tree, growing to heights of up to 16 to 27m. It is common in towns and cities where it is often used along boulevards or around squares.
In the UK, poplar flowers in spring, with peak pollen production during March. The common silver birch is a single-stemmed, deciduous tree up to about 25 metres tall, with distinctive silvery bark. Birch pollen is highly allergenic and is a significant cause of asthma and rhinoconjunctivitis.
Pollination occurs from spring to early summer, peaking between April and May. The European ash is a broad, deciduous tree, growing up to 35 m in height. Ash trees are wind pollinated, with pollen travelling up to metres from the tree. They spread large amounts of pollen during the flowering season, which in the UK is from March to May, with the peak occurring in April. The London plane tree is easily identified by its distinctive bark which peels in large flakes.
It is commonly found in urban areas of the UK, planted along streets and in squares. Over half of the trees found in central London are of this species. London plane is wind pollinated and pollination peaks during May. Oaks are large deciduous trees with broadly spreading canopies, found throughout the UK both in rural areas and in urban or suburban parkland. Flowering generally occurs in spring but may vary based on local temperatures and weather conditions, with pollination peaking around May.
Oilseed rape is a common food crop in the UK, grown principally for oil production. Oilseed rape fields are easily recognisable by the bright yellow flowers which are characteristic of this species. It is partially wind pollinated, with peak pollen release occurring from May to June. Pine is a coniferous tree growing up to 35m in height, with upward pointing branches and a narrow, tapering shape. The majority of species flower in spring and early summer in the UK, peaking around May. While the pollen count is high, the individual pollen grains are relatively large, which can reduce sensitisation.
Grass pollen is one of the most common causes of allergic rhinitis hayfever , and may also cause contact dermatitis in sensitised individuals. In the UK the grass pollen season runs from spring through to early autumn, with its peak in summer. Activities such as mowing and baling of hay may increase levels of pollen locally. Lime trees are a common ornamental tree in the UK, growing to as much as 30m tall.
They may be found in parks and ornamental gardens or lining streets or avenues. Limes flower in summer, with peak pollination usually occurring in June. Nettles are a well-known weed which are renowned for their painful sting.
The leaves are heart-shaped and the flowers usually appear in June, but have no or very little allergenic potential. A well-known weed which everyone remembers for its painful sting.
Nettles grow mainly on wastelands in nitrogenous soil. The flowering season stretches from June to September, but offers little or no allergenicity. Both of these common country herbs have small, inconspicuous reddish flowers. They usually grow in meadows and pasture land, and sometimes in sandy coastal areas. Their flowering season extends from April to September, with pollen producing moderate to high allergenicity.
Numerous species of grasses grow all over the UK, releasing pollen from May to September, with June and July as the peak time. The species with the highest allergenic potential are those which grow tall in. This shrubby, woody-stemmed weed is found in wasteland and can grow to a height of 2 meters. The leaves are slitted, with white hair on the underside. Flowers are very small, and yellow to reddish-brown colour.
In Europe, the start of the season is late July. Mugwort shows high allergenicity. Alternaria is a fungus which appears as dark lines, dots, or circles up to the diameter of a plate, and is often found in bathrooms. It grows naturally outdoors on plant material, but also indoors on wood, silicone seals, walls or textiles, wherever condensation or other sources of damp provide enough water.
Spore loads are sometimes very high after summer rain, and thermal convection helps the spores to become airborne when the soil dries out. Alternaria spores have moderate to high allergenic potency. Cladosporium is a common mould all over the world. Outdoors, it is frequently found on rotten organic material such as plants and wood, indoors, it can be found on walls and objects affected by water damage, and even on food in refrigerators. The small spores have a distinctly roughened surface, pale brown to dark brown in colour.
Like alternaria, the season starts mid-June, peaks in July and August and ends with airborne spores in September and October. Cladosporium spores have moderate allergenic potency. Allergic reactions to house dust mites are very common. Sometimes known as dust allergy, classic symptoms include runny, itching, or blocked nose, itching or swollen eyes, and cough, particularly in the morning after getting up. These are smaller than ordinary pollen grains, coated with a thin hull layer which decays in time, releasing even smaller allergenic particles.
Cat and dogs are perennial allergens, and their dander hair and skin cells is the biggest cause of pet allergies in the UK.
Pets shed hair and skin cells all the time, especially during grooming. This dander settles on bedding, carpets and furniture, and floats around in the air when disturbed. Touching and stroking cats and other animals can also spark allergic reactions such as skin irritations and itchy rashes. We reserve the right to change coupon offers at any time. Home Understanding Allergies What are allergies? How do allergies work?
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