Useful facts on animal allergy (dyreallergi)
Useful information concerning animal allergy – NAAF’’s fact sheet
All fur-bearing animals, and hence most domestic pets, can trigger allergic reactions. Individuals may react, not only to the hairs in the coat and dander/flakes from skin, but also to allergens (proteins) from the animal’s sebaceous and salivary glands and urine. These are small airborne particles which mix with other airborne dust. When this air is breathed in it can bring about allergic reactions. Dust from horses, dogs and cats contains 10-20 different allergenic substances.
Who can get animal allergies?
It is most common to develop allergies during childhood. Animal allergy is most common among persons with asthma and frequently occurs along with mite allergy. If a child has not shown any sign of allergy by the age of 12-14 years, the likelihood of him or her developing animal allergy is reduced; however, adults can also develop animal allergy.
It is difficult to predict which particular animals individuals will react to. In order to develop an allergy, one must first have been in contact with the specific allergen, and it may be some time before allergy symptoms become obvious.
Which animals can trigger allergy?
Most domestic animals, including miniature pigs, naked mice, chinchillas and short-haired Chinese poodles will, as stated, have the potential to trigger an allergy. Small animals such as mites, mosquito larvae and cockroaches can also trigger an allergy.
Horses and cats are the animals that carry the most ”aggressive” allergens. Horses are large animals and produce greater quantities of allergens than smaller animals. Cats have a large radius of movement and will spread allergens wherever they roam. Dogs generally have the closest contact with people and therefore cause the most common forms of animal allergy. There is a difference between how much and which type of allergens the various breeds of dog give off; however, all breeds of dog, whether small or large, short or thick-coated, produce allergens.
The only domestic animals which do not provoke allergy are aquarium fish (although some may react to fish food) and reptiles, e.g. turtles. In Norway the import of reptiles is prohibited; however, the Norwegian Food Safety Authority permits the importation and keeping of some types of turtle, where allergy is given as the reason for keeping a turtle.
A blood test or skin-prick test must be carried out in order to establish whether an individual has an allergy to an animal. If an allergy towards the animal species already exists, then this type of test will have a positive result. However, it is also possible to have positive test results without experiencing the symptoms of an allergy.
It is not possible to test in advance whether a child will tolerate a certain animal. A negative result from a prick test cannot predict anything concerning future reactions.
Symptoms and treatment
Common reactions are a blocked, runny nose, itching and runny eyes and asthma. Some individuals may also suffer eczema and urticaria (nettle-rash). Exposure to cat allergens has been shown to be a particular risk factor for acute asthma in those with cat allergy.
Removal of the allergy-provoking animal from the allergic individual’s surroundings is the most effective treatment. Prevention of animal allergy with medications such as cortisone nasal spray and/or antihistamines, either in tablet form, nasal spray or eye drops, is not an ideal solution, but may be necessary where exposure to the animal allergen is unavoidable.
Immunotherapy or so-called allergy vaccination, where dog or cat allergens are injected under the skin, may be beneficial in the longer term; however, this is contingent on that the allergy-provoking animal is removed from the allergic person’s home environment.
Here it is important to differentiate between secondary and primary prevention.
Secondary prevention: In the case of proven allergy to a fur-bearing animal, the first preventive advice should be to avoid getting a pet. However, animal allergens are difficult to avoid completely, as animal hairs attach themselves to clothing and will therefore be found in schools, in kindergartens and on public transport.
If one or more children have an animal allergy, kindergarten personnel and teachers should ask other parents to dress their children in clothing that has not been in contact with animals. It is also important that outdoor clothing is hung in a cloakroom or similar and not taken into the classroom. There should be a general ban on cats and dogs in kindergartens and schools.
Various cleansing lotions than can be used on the animal (PetalCleanse) to reduce the amount of allergens, have been introduced on the market as agents against animal allergy. The amount of allergens in the fur of a cat is also reduced via normal bathing; however, this is not recommended as a way of reducing animal allergies. At best, the cleaning agent will help temporarily and will only be relevant for those with milder forms of animal allergy. Even if a cat is bathed, cat allergens will still be found in house dust. Another issue is that frequent bathing of the animal may almost be perceived as animal cruelty.
Primary prevention: There is no longer any basis to advise anyone against getting a dog or a cat if one wishes to prevent the development of asthma or allergies, not even where allergies are found in the family. A study based on data from around 20 000 European children, who were followed from birth to school age, found neither increased nor reduced risk of asthma or allergies in those that kept pets at home. A recently published study from Denmark indicates rather the opposite, that keeping animals on a farm or at home can have a preventive affect on the development of allergies in children. It seems therefore that it is no longer correct to advise families with children against getting pets.
Pets bring a great deal of happiness to many families. Blood tests and prick tests carried out before getting a pet have little value in predicting whether a child will develop an allergy or not. If a family with allergies wishes to get an animal, or not, is a decision that the adults in the family must take independently. It can be difficult to let go of an animal to which you have formed a strong bond if you begin to develop an allergy. Therefore, parents should also consider whether they are willing to take such a risk, if a child develops an animal allergy. The Association for Re-homing of Animals (FOD) can be contacted if necessary.
Can animals protect against asthma and allergies?
Recent studies suggest that keeping pets at an early stage in life may protect against the development of asthma and allergy. The results are explained as being due partly to the fact that tolerance may be developed to the animal allergen and partly to the animal bringing with it various types of bacteria which can strengthen the immune system. More research is required in this area, but results thus far strongly indicate that contact with animals can have a protective effect. This is a complex field, however, and it is not possible to give clear and unambiguous advice. At this time, it is probably not correct to positively recommend that people get animals for preventive purposes – however it is also not correct to advise against it.
Facts concerning animal allergy have been drawn up in consultation with NAAF’s medical board.
Most recent revision: January 2013.