The Australasian Society of Clinical Immunology and Allergy

Allergies and asthma are very common in Australia and New Zealand. Around 1 in 3 people will develop allergies some time during their life, and about 1 in 10 will develop asthma. Far from being a trivial inconvenience, allergies have a significant impact on quality of life and are associated with medical. Some allergies are even life threatening. Unfortunately, many people confuse myth with reality in the way they view and treat allergies and asthma.

Some of these common 'allergy and asthma myths' were uncovered from a US survey. They have been added to and adapted for Australia and New Zealand.

Myth 1 Allergies are uncommon

Reality: The frequency of allergic disease has approximately doubled in the last 25 years.
In Australia and New Zealand, around:

• 1 in 3 people will develop allergies at some time during life;
• 1 in 5 will develop atopic dermatitis;
• 1 in 6 will have an attack of hives (urticaria);
• 1 in 10 people have asthma;
• 1 in 20 will develop a food allergy (usually transient); and
• 1 in 100 will have a life-threatening allergy known as anaphylaxis.

Myth 2 Allergies are harmless

Reality: Allergies are a serious problem in Australia and should not be ignored. Untreated allergies have a significant impact on quality of life.
Hayfever, for example, results in poor quality sleep, fatigue and daytime sleepiness.
Adults find it harder to think and function at work, suffer from greater absenteeism and more work-related injury. They are more irritable and moody than healthier people and find it harder to make important decisions. School-aged children with hayfever do poorly in examinations and often cannot recall information taught during class.
Untreated allergies can also worsen other chronic respiratory problems such as asthma, sinusitis and skin disorders such as eczema and urticaria (hives).
Some allergies to foods, drugs and insect stings can lead to a potentially life threatening reaction called anaphylaxis - a systemic allergic reaction which can be fatal, and leads to the death of 10 to 20 Australians each year.

Myth 3 Smoking does not trigger asthma

Reality: Babies who are born to smoking mothers have a greater chance of developing asthma than children of non-smoking mothers. Smoking is also a known trigger of asthma attacks and should not be ignored. So if you must smoke, do it outside and away from your children.

Myth 4 Flowering plants cause hayfever

Reality: Seasonal allergic rhinitis, commonly known as hayfever, is caused by allergy to pollen, rather than hay.
Pollen allergy tends to be due to air borne pollen from wind pollinated grass, weed and tree species.
By contrast, the pollen of flowering plants is large and sticky, does not blow very far, and requires birds and bees for pollination. Therefore, when people complain that scented flowers trouble them, it is usually due to chemical irritation from the perfume that makes them sneeze rather than the pollen.

Myth 5 Moving interstate can cure allergies

Reality: Allergic rhinitis may be triggered by wind-blown pollen in spring and summer, or
by other allergens such as house dust mite, animal danders and mould spores all year round.
Moving away from the source of allergen (such as interstate, or from inland areas to the coast) may temporarily relieve allergies. Unfortunately allergic people are also prone to developing new allergies, and often symptoms reappear within a few years with exposure to new plants, or other sources of allergen such as moulds or house dust mite.

Myth 6 Continuous exposure to animals will desensitize you to them

Reality: If you are allergic to an animal, continuous exposure will not decrease your allergy.
In fact, 1 in 3 people who are already allergic and exposed to indoor pets will become allergic to them as well over time. Keeping indoor pets is also associated with asthma and the need for more medication. If you are allergic to animals, sensitivity often worsens with ongoing exposure.
The best way to relieve symptoms is to avoid the animal, minimize exposure to household pets by removing them from the home or at least keeping them out of the bedroom, have hard flooring and wash the animal regularly to reduce the amount of allergen they shed.

Myth 7 You cannot develop an animal allergy if you do not yourself have pets

Reality: Animal allergens, particularly cat and horse allergen can be carried on clothes. This may sensitize other people who do not have pets themselves and provoke symptoms in sensitized individuals.

Myth 8 Some animals are better for people with asthma and allergies

Reality: The allergens in cats and dogs are derived from the oily secretions of the skin. Even if some breeds do not shed hair, the allergen still becomes attached to all the dust particles in the house (eg the walls, carpets, bedding, clothing and drapes). It does not easily break down with time. Allergen is continuously suspended in the air, even if the animal has been removed from the house or is not in the bedroom.
While the amount of allergen shed by an individual animal may vary with a number of factors (sex, whether de-sexed or not, short or long hair, hair or 'wool'), the actual allergen is the same amongst species. Allergies to other animals such as guinea pigs, horses and mice have also been described. Even iguanas can trigger allergies. There are no hypoallergenic animals!

Myth 9 Eliminating wheat and milk helps asthma and hayfever

Reality: Diet plays a minor role in the management of asthma or hayfever. While some children with food allergies go on to develop eczema, asthma or hayfever as well, taking all people off wheat or dairy products as a routine is almost always a waste of time. Such diets can adversely affect nutrition (particularly in children) and directs effort into unproductive areas.
When food allergy does occur, reactions are usually of rapid onset, severe and obvious. They are almost always accompanied by rashes, throat swelling, vomiting or sometimes a more subtle worsening of atopic eczema. Nuts, fish, shellfish, milk and eggs are the most common food allergies in children.
Scientific studies show no evidence that milk either increases mucus production or worsens asthma!
More commonly, patients will react to cold drinks (such as milk) with wheezing because of the inhalation of cool dry air while it is being drunk. Bakers can sometimes develop asthma from inhaled wheat flour.
Eliminating wheat and milk will help your allergy, but only if you are allergic to wheat and milk!

Myth 10 Colours and preservatives are a common cause of asthma

Reality: Preservatives like sodium metabisulfite (220, 221, 222) in wine, dried fruits, vinegar, grapes and some fruit salads can worsen, but do not cause asthma. Inhalation of small amounts of sulphur dioxide released may cause a reflex contraction of the bronchial tubes. Monosodium Glutamate (MSG) also has a bad reputation for triggering asthma in some people, but scientific studies have shown this to be a relatively rare problem. Benzoates (used in cordials) can sometimes cause problems.
Unfortunately, allergy testing is unreliable for confirming sensitivity to these substances.

Myth 11 Alternative tests and treatments are just as effective as conventional tests and medications for allergy and asthma

Reality: There are several unorthodox 'tests' for allergy such as cytotoxic food testing, Vega testing, kinesiology, iridology, pulse testing, Alcat testing and Rinkel's Intradermal skin testing. These have no scientific basis, are unreliable and have no useful role in the assessment of allergy.
On the other hand, Skin Prick Tests and blood (RAST) tests are reliable and scientifically validated tests. These tests can help your doctor define the cause of your allergies and are rebated by Medicare in Australia.
Many Australians use dietary supplements, complementary and alternative medicines to treat or prevent various ailments. Sometimes they use them in conjunction with medications prescribed by their doctor. Regardless of your decision in this regard, it is important to let your doctor know you are taking them. This is because side effects and interactions with medications may occur. It is important to realise that alternative medicines have not been subjected to the rigorous study of effectiveness and side effects that conventional drugs undergo.

Myth 12 Allergies and asthma can be cured

Reality: There is no cure for asthma or allergies. The closest thing to a cure for allergy is immunotherapy, which is effective for treating some allergies like hayfever, asthma and stinging insect allergy, but not for treating food allergies. With appropriate diagnosis and management, however, most asthma and allergy sufferers will lead normal, active lives with little disturbance to their quality of life.

Myth 13 Asthma and hayfever sprays are dangerous

Reality: Inhaled medications, including corticosteroids (preventative treatment) are commonly used to treat asthma. They are very safe and effective, as long as they are used at an appropriate dose under medical supervision. Similar medications are used to treat severe hayfever. There is no evidence that long-term use of these thins the lining of the nose, although medical advice should be sought if side effects occur.

Myth 14 Many children grow out of their asthma and allergies

Reality: Allergies last for years! For example, it is known that:

• 85 per cent of children with atopic dermatitis (eczema) improve by their teenage years, but often have dry and irritable skin and problems with soap and some cosmetics for life;
• 80 per cent of children diagnosed with allergic rhinitis will still have trouble 10 years later; and
• 40 per cent of young adults will still be sneezing 20 years later.

Asthma can also persist. Some children have asthma symptoms that improve or disappear during adolescence, whereas others will worsen. Those with severe or persistent asthma tend to remain much the same as adults. Even when symptoms disappear completely, they may return later on in life, particularly with infections or exercise.
Allergic reactions to cow's milk, soy or egg in infants often resolve by the time a child enters kindergarten, but others (such as peanut, tree nut or seafood) usually persist for life.

Myth 15 Allergy drugs are dangerous and make you sleepy

Reality: Older sedating antihistamines have been available for decades. Their only advantage is that they are inexpensive. They often cause drowsiness and interfere with people's ability to drive or operate machinery safely. Their impact is even more dangerous when alcohol is consumed as well. Adults using sedating antihistamines often find it difficult to think clearly, elderly patients may get confused and children often become sleepy or irritable in class. It is therefore important to check medication labels and to consult a pharmacist or doctor before you consider using these medicines.
Fortunately, non-drowsy antihistamines are now readily available from pharmacies (eg Claratyne, Telfast, Zyrtec). These medicines are just as effective (and probably more so), rarely make people drowsy, have been proven to be safe when driving and hardly ever make children irritable or hyperactive. Because they last a lot longer in the body, they are also more convenient to take (typically once daily).

Myth 16 There is no way of getting rid of house dust mites

Reality: The greatest concentration of dust mites and their allergenic faecal particles is in carpeted bedrooms and bedding and in houses where there are domestic animals, especially cats. Polished boards, lino or other impervious floor coverings, regular washing of bed linen and encasing mattresses and pillows in barrier encasing will substantially reduce exposure to dust mite allergen. Although it will not eradicate the dust mite, vacuuming once per week will reduce the number of dust mites, particularly if HEPA filters are used.

Myth 17 A little bit of peanut does no harm

Reality: Contact with a trace amount of peanut can kill a peanut allergic individual.

Myth 18 Damp houses are just as healthy as dry houses

Reality: Damp houses have a higher mould content than dry homes and indoor mould is a common cause of perennial allergic rhinitis, sinusitis and bronchitis as well as asthma.

Disclaimer

The content of this article has been reviewed by ASCIA members, represents the available published literature at the time of review and is not intended to replace professional medical advice. Any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner.

For further information on allergy, asthma or immune diseases,
visit http://www.allergy.org.au/ - the web site of
ASCIA is the peak professional body of Clinical Allergists and
Immunologists in Australia and New Zealand.

Contact details
PO Box 450 Balgowlah NSW Australia 2093