Hay Fever

Hay Fever

Definition:

• Hay fever is caused by an allergic response to airborne substances, such as pollen - unlike a cold which is caused by a virus. 
• The time of year in which you get hay fever depends on what airborne substance you are allergic to. 
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• Despite its name, hay fever does not mean that the person is allergic to hay and has a fever. 
• Hay is hardly ever an allergen, and hay fever does not cause fever. 

What are the risk factors for hay fever?

A risk factor is something that increases a person's chances of developing a disease or condition. Below are some risk factors for hay fever:

·         Family history (inheritance, genetics) - if you have a close family member who has/had hay fever, your risk of developing it yourself is higher. There is also a slightly higher risk if a close family member has any type of allergy.

·         Other allergies - people with other allergies are more likely to suffer from hay fever as well.

·         Asthma - a significant number of people with asthma also have hay fever.

·         Gender and age - hay fever affects more young males than young females. Before adolescence, twice as many boys as girls have hay fever. However, after adolescence many boys outgrow it and slightly more girls than boys are affected.

·         Birth date - people born during the high pollen season have a slightly higher risk of developing hay fever than other people.

·         Second-hand smoke - infants and babies who are regularly exposed to cigarette smoke during their first years of life are more likely to develop hay fever than babies who aren't.

·         Being the first child - a higher percentage of firstborn children eventually develop hay fever, compared to other people.

·         Babies from smaller families - a higher proportion of babies with no siblings, or just one sibling develop hay fever later on compared to babies born to larger families.

·         Babies born to high income families - babies born to families with a high standard of living have a higher risk of developing hay fever later on, compared to other babies.

Experts believe that the last three risk factors are linked to childhood infections. If a baby and/or small child has had fewer infections, there is a greater risk of autoimmune problems.

How is hay fever diagnosed?

Generally, doctors can make a diagnosis based on the symptoms, which are usually fairly obvious. 
A blood or skin test can be followed up to identify which substance(s) the patient is allergic to.

·         Skin test - the skin is pricked with a minute amount of a known allergen (substance that some people are allergic to). The amount of IgE antibodies (immunoglobulin E) is measured. IgE antibodies are produced in high amounts if a person has an allergy to something.

·         Blood test - the test simply measures the level of IgE antibody in the blood. If it is zero there is no sensitivity, whereas 6 indicates very high sensitivity.