What is pollen?
Pollen grains are small particles of varying diameter and weight, which are released into the air and spread by the wind in order to pollinate plants of the same species. The pollen types of greatest significance in pollen allergy come from the tree species alder, hazel and birch. Other producers of pollen include wormwood and certain grass species, in particular timotei and orchard grass. Mould spores can give rise to the same symptoms as pollen. Pollen allergy occurs where individuals react allergically to certain proteins found in some pollen types. In technical language pollen allergy is termed seasonal allergic rhinitis or hay fever in everyday speech.
We come into contact with pollen by breathing it in through the airways, as well as it attaching to the skin, hair and eyes. For most people this is unproblematic, however, in an allergic individual, the immune system is activated and an inflammatory response occurs in the nose and/or eyes. The body reacts to the protein in pollen causing release of histamine and other inflammatory substances which results in discomfort in the form of sneezing, runny nose and itchy eyes.
Who gets pollen allergy?
Pollen allergy occurs most commonly in the age group 5-40 years and more and more people seem to be affected by the illness.
Where is pollen found?
Pollen is present in large quantities in the outside air at certain times of the year. During the spring, pollen comes from trees and during the summer the most common sources of pollen are grass and wormwood. In general there is less pollen in coastal and mountain areas. Grass and wormwood pollen spread over shorter distances – a few hundred metres, in contrast to tree pollen which can spread for miles. This applies in particular for birch pollen which, for example, in stable, south-easterly winds can spread from parts of southern Finland or the Baltic to Northern Norway.
The pollen warning provides updates every weekday throughout the summer and provides information in respect of where in Norway it is the season for the various pollen types most relevant in relation to allergy. For example, the birch pollen season in Oslo has passed before it commences in Tromsø.
(See also the pollen calendar/pollen warning at www.naaf.no).
What are the symptoms of pollen allergy?
Symptoms of pollen allergy include runny, blocked nose and sneezing. The eyes stream, itch, redden and become puffy. Some sufferers also suffer from asthma during the pollen season. These are barely recordable changes in terms of the environment, whilst other troublesome fluctuations are only noted by sufferers.} The whole body reacts; the allergic individual feels fatigued and out of sorts, with reduced ability to concentrate and ability to learn. Many individuals experience that the illness has knock-on effects in terms of their work and school results.
Many individuals with pollen allergy experience cross reactions – see Useful facts on cross reactions.
How is the diagnosis of pollen allergy made?
You can be skin prick tested by a doctor specialising in allergies in order to establish whether you react to pollen, house dust, mould, particles from animals, etc. A small drop containing a test substance, e.g. a pollen solution, is placed on the skin. A small hole is made in the skin through this drop. A red, itching area with a white blister marks the allergy. Such a reaction, together with typical allergy symptoms, indicates that you are allergic to the pollen type contained in the solution.
It is important not to use allergy tablets for the 3-10 days preceding the test.
Allergy tests involving blood tests can also establish the presence of pollen allergy.
Prevalence of pollen allergy:
We estimate that 20 % of the population suffer to a greater or lesser extent from pollen allergy - approximately 900 000 Norwegians.
In Sweden, where studies have taken place on the increase in pollen allergy amongst adults, the following figures were obtained: Figures for adults suffering from pollen allergy increased from 8 % of the population in 1981 to 19 % of the population in 2003. It is therefore obvious to conclude that Norway could have the same formidable increase.
Measures/good advice in pollen allergy:
- In the pollen season individuals easily become hypersensitive to other allergens and irritants. Be careful in respect of hygiene, strong smells, tobacco smoke etc.
- Avoid airing the house when pollen release is at its greatest, i.e. between mornings until after mid-day.
- Do not dry clothes outside in the middle of the day. The pollen grain attaches easily to the clothing.
- Wash/rinse the hair before bedtime.
- Physical activity should take place at times when pollen spread is at its lowest. Some individuals may benefit from using a protective mask, e.g. when cycling.
- Use of sunglasses may reduce the eye symptoms.
- School pupils and students with pollen allergy may request (in good time) to have their exam period extended. A medical certificate must be obtained.
Treatment of pollen allergy:
The primary goal in all allergy treatment is to try to avoid the substance to which one is intolerant.
A number of medicines used in treatment of pollen allergy are available. Treatment may take the form of a nasal spray, eyedrops, allergy tablets (antihistamines and leukotrien antagonists), inhaled medications or injections. One new drug – Xolair – is now approved for use in Norway. It is intended for the sickest asthma patients in whom allergy is significant in terms of their disease.
The doctor will help you in choosing which medicine is best for you. It is important to understand that the allergy medicines are preventive, and it is known that they can take 1-2 weeks before full benefit is achieved. They must be used regularly every day throughout the pollen season, even where the symptoms disappear on individual days where the pollen count is low.
It is important to understand that the symptoms may be significantly exacerbated by irritants such as tobacco smoke, exhaust fumes, dust, perfume, wind, temperature fluctuations, infection, emotional and hormonal factors, as well as alcohol.
(See also separate fact-sheet on allergy vaccination)