Pets produce dander, and the protein in it can cause severe allergic reactions for some people. Pet dander can easily become airborne and inhaled. Unfortunately, it is also very sticky and can cause allergic reactions for long periods of time (up to 20 weeks). If you share your home with a pet, you will find everything here that you'll need to know in order to go about creating a healthy indoor environment that will be beneficial to controlling both your, and your pet's, allergy symptoms.
Pet dander is the name given to microscopic skin flakes shed by animals. It is a bit like dandruff flakes, only smaller at around 2-3 microns in size. Animals shed a number of allergenic proteins in their urine, sweat and saliva. These body fluids adhere to the skin life for example when a cat cleans itself.
Cat dander is the most common inhaled allergen source after house dust mite and pollen. Other animals commonly kept as pets, such as dogs, mice and guinea pigs, may also cause allergic reactions. Pet allergens are widely distributed in the air, because they are so light, and they remain airborne for several hours before settling (only to be easily stirred up again). Indeed, they may persist for many months after an animal has left a house. The best way of avoiding pet dander is obviously do not have a pet. If you have a pet and are determined to keep it, then there are still various measures you can take to cut down on pet allergen exposure, from controlling the animal's access to certain rooms to using an effective air purifier to trap dander particles.
Pet allergies are known to play a role in:
People with atopy, a tendency to allergy, should avoid owning pets if possible. Even if you are not allergic to the pet at present, continued exposure could eventually cause sensitisation, leading to allergic symptoms.
In an allergic person, exposure to certain proteins in animal dander will cause the immune system to over-react and cause an overproduction of Immunoglobulin E (IgE). The IgE attaches itself to mast cells, which are a type of immune cell, causing them to produce the chemical histamine. It is the histamine which causes allergic symptoms like swelling, redness, watery eyes, coughs and sneezing and also why the main drugs for allergy are called antihistamines.
Pet dander is very sticky and stays on people’s hair, clothes and other belongings for long periods of time, and thus travels to offices, kindergartens, planes etc.
What animals cause allergy problems?
These animals can all cause pet allergy:
Male cats shed more allergen than females, and cats shed more allergen than dogs. Horses produce very powerful allergens and old mattresses stuffed with horsehair can produce symptoms. Snakes, lizards and other reptiles, and even insects may shed dander-like skin particles into the air. Fish are perhaps the only companion animals not associated with allergy.
Four main cat allergens have been identified and studied. The two main ones are Fel d1 and Fel d4 (Fel stands for Felis – the scientific name for a cat). Fel d1 is found in a cat's sweat and Fel d4 in its saliva. The minor allergens are Fel d2 and Fel d3 found elsewhere such as urine.
The two main dog allergens are Can f1 and Can f2 which are found in dog saliva. Can stands for Canis the scientific name for a dog.
The dog genome does not, as far as we know, vary so much between species that some have lower allergen levels than others. Therefore, all dog species produce the same amount of allergen in their secretions. Any differences probably relate to the length of the dog's coat and how much hair it sheds, or maybe how much it sweats. There are around 60 breeds of dog that are said to be hypoallergenic - generally, as you might expect, those which are hairless or have short coats and therefore do not shed as much. Examples include various breeds of terrier and former US President Obama's dog (Bo, The First Dog) who is a Portuguese water dog, because one of his daughters is allergic. A recent research study looked at the amount of allergen shed by different dog species and found that hypoallergenic dogs do not shed significantly less allergen than other breeds.
To learn more about dog allergies visit our Dog Allergy Information page.
All allergen avoidance / environmental allergen control is important. The following guidelines should help: