Facts about hay fever
Hay fever is also known as seasonal allergic rhinitis. It is the most common of all allergic conditions affecting around 1 in 5 people in the UK.
What is hay fever?
Hay fever is an allergic reaction to pollen grains or spores produced by trees, grass, flowers and moulds. It commonly occurs between early spring and autumn but, for those allergic to certain tree pollens, symptoms can start as early as January.
What causes hay fever?
Hay fever is caused when the body's defences overreact to pollen in the air. The pollen causes a release of a substance called histamine from the cells in the body and, as a result, stimulates the allergic reaction that causes many of the symptoms associated with hay fever. The amount of pollen in the air depends on the time of year and the weather.
The pollen and spore seasons
What is pollen?
Pollens are microscopic particles produced by flowers, which enable plants to reproduce by forming fruits and seeds. Certain pollens are only active at certain times of the day, so sufferers who are allergic to pollen usually know when to take precautions.
When we have hay fever we will show a slightly different pattern of symptoms, depending on the particular pollen or spores we are allergic to. Hay fever symptoms can be similar to a cold, the general symptoms of hay fever are:
- A runny or blocked nose
- Itchy or watery eyes
- Frequent sneezing
- An itchy throat, mouth, nose and ears
Less common symptoms of hay fever are:
- A loss of smell
- Facial pain (caused by blocked sinuses)
The higher the ‘pollen count' is, the worse hay fever can be. The pollen count is the number of pollen grains found in each cubic metre of air. Hay fever symptoms tend to begin when the pollen count is over 30. The pollen forecast is usually given as low, moderate, high or very high.
Pollen forecast and pollen count relationship
Very High 150 pollen grains per cubic metre
High 50 to 149 pollen grains per cubic metre
Moderate 30 to 49 pollen grains per cubic metre
Low 30 or less pollen grains per cubic metre
Hay fever prevention
To avoid exposure to pollen and spores, hay fever sufferers should:
- check the weather reports for the pollen count and stay indoors when the count is high
- wear wrap around sunglasses to protect eyes from pollen
- keep doors and windows shut during mid-morning and early evening, as this is when there is most pollen in the air
- avoid grassy areas, such as parks and fields
- get someone else to cut the grass for you
- change clothes and take a shower after being outdoors to remove pollen
- keep car windows closed, and consider buying a pollen filter for the air vents in the car
- keep fresh flowers out of the house
- not smoke in the house or breathe in other peoples smoke as this may irritate their symptoms
Mould spores also aggravate hay fever. They are released when there is a sudden rise in temperature in a moist environment, so we suggest hay fever sufferers:
- keep the house dry and well ventilated
- do not dry clothes indoors, or store clothes in damp cupboards
- use dehumidifiers to help reduce damp
| See more: A Short Guide to Hay Fever - Infographic |
| More info: Allergy Screening Service |
| Watch: Hay Fever & Allergy video |
| More info: The Benefits of an Allergy Screening Test |