Cat Allergy: An Overview
Cat allergy is a condition that causes allergic symptoms on exposure to cats.
This is a very common problem affecting people all over the world.
About 10-20% of the American population could be allergic to cats and dogs.
Cat allergies seem to be twice more common than dog allergies in the American population.
What Causes Cat Allergy?
The immune system is designed to fight harmful substances that come in contact with the body.
In some cases, the immune system may overreact to harmless external substances, triggering allergic reactions.
In the case of cat allergies, it is substances produced in cats' bodies like saliva, dander (skin flakes), and urine that trigger allergies.
These bodily substances contain proteins that the human immune system assumes are dangerous and triggers allergic reactions.
These proteins are called cat allergens.
According to the World Health Organization, there are eight cat allergens identified.
The most important of these allergens is Fel d 1.
This is a secretoglobin protein found in the skin and saliva of cats.
According to experts, this protein is airborne and can remain in the atmosphere even after the cat has left the room.
Two other common allergens are Fel d 4 and Fel d 7.
Both these are lipocalin proteins found in cat saliva.
What Are The Symptoms of Cat Allergy?
Here are some of the common symptoms of cat allergy.
- Sneezing
- Runny nose
- Nasal congestion
- Watery, red, itchy eyes
- Tightness in the chest
- Coughing or wheezing
- Shortness of breath
- Skin rashes, hives
- Itching and redness in the skin
- Anaphylaxis (causing life-threatening allergic reactions) in rare cases
Genetics of Cat Allergy
IL1 Gene and Cat Allergy
The IL1 gene produces a protein called interleukin-1 alpha.
These proteins are found in the immune system and play a role in inflammation and protection from harmful invaders.
The Single Nucleotide Polymorphism (SNP) rs10189629 is located within the IL18R1–IL1RL2 gene region.
The A allele of this SNP is considered beneficial/protective against developing cat allergies.
| Allele | Implications |
| A | Lesser chances of developing cat allergies on exposure to cats |
| C | Normal chances of developing cat allergies on exposure to cats |
Risk Factors For Cat Allergy
Gender
According to a 2020 study, the males are at an increased risk of producing immunoglobulin E (IgE) antibodies in response to normal environmental and airborne allergens compared to the females.
This means that sensitization risk is higher in men than in women.
Sensitization is the process of becoming hypersensitive to a stimulus.
In this case, it is the development of allergic symptoms on exposure to cats.
Childhood Exposure
A 2002 study tried to understand the relationship between childhood exposure to cats or dogs and the risk of allergic sensitization.
According to this study, children exposed to two or more cats or dogs within the first year of their life may have a reduced risk of allergy sensitization to multiple allergens produced by these pets.
Age Of Becoming A Pet Owner
A 2012 study analyzed the effects of getting a cat for the first time in adults.
This study analyzed 4468 adults who either didn’t own a cat or had bought home a cat for the first time as adults.
According to the study, in people who haven’t been exposed to cats much in their childhood, getting a cat home for the first time in adulthood may double the risk of developing cat sensitization.
Diagnosing Cat Allergy (Prick test, Intradermal test, Bood test - IgE)
There are different ways of diagnosing cat allergies.
In fact, since about 96% of the patients react to only the major cat allergen - the Fel d 1, diagnosing cat allergies is straightforward when compared to diagnosing dog allergies.
Below are ways to diagnose cat allergies.
Allergy Prick Test
An allergy prick test is done by pricking a small portion of the skin using a needle and placing a small amount of allergen on that area.
If you are allergic to cats, the area starts showing symptoms like redness, swelling, and itching.
Intradermal Test
The intradermal test is also similar to a prick test.
However, here, the allergens are deposited under the skin.
This is slightly more sensitive than a prick test to diagnose cat allergy.
Bood Test - IgE
The patient’s blood is drawn and sent to the lab for testing.
People whose bodies react to cat allergens develop immunoglobulin E (IgE) antibodies, which can be detected in the blood.
This is safer for those worried about developing extreme skin sensitivities from the first two methods.
Treating Cat Allergy
- For mild allergic symptoms, Over The Counter (OTC) antihistamines may help.
However, these should not be used frequently and without consulting your doctor.
Prescription antihistamines and corticosteroid sprays can both be given in combination to deal with chronic allergy symptoms.
- Some people may prefer getting allergy shots regularly to reduce the severity of the allergic reactions.
Allergy shots contain very small amounts of the allergens and slowly help desensitize the immune system to prevent allergy triggers.
- Leukotriene inhibitors are medications that stop the production of leukotrienes, which are chemicals that cause tightening of airway muscles and breathing problems.
Managing/Living With Cat Allergy
Avoid Exposure To Cats
The easiest way to prevent an allergic trigger is to avoid exposure.
If you don’t have cats yet, do not bring them home.
Avoid visiting homes that have cats.
If you must, wear protective masks and avoid touching the pets.
Avoid Using Upholstery
Upholstery is padded textiles that cover furniture to make them soft and comfortable.
These trap cat allergens very easily, and when you sit on or use such upholstery in houses with cats, your risk of exposure increases.
Avoid Using Carpets And Rugs
Low-lying carpets and rugs also trap cat allergens and retain them.
If you own cats, avoid using carpets and rugs.
If you must, then make sure these are cleaned regularly to bring down exposure.
Restrict Pet Movement
You could try and restrict your cat’s movement to specific rooms.
This way, you will have safer spaces to be in during an allergic trigger.
If you are allergic to cats, avoid having them in your bedroom.
Use HEPA Filters
High-Efficiency Particulate Air (HEPA) filters can remove up to 99.97% of airborne particles in the atmosphere.
In families with both cats and cat allergic individuals, using these filters may help reduce the frequency of allergic triggers.
Use Gloves And Masks While Petting Cats
If you love cats but are allergic to them, wear masks and protective gloves while petting them.
Also, make sure you change your clothes once you are done petting.
Do avoid bringing the cat close to the face while playing with them.
Groom Your Cats Regularly
Cats have to be groomed regularly to prevent the risk of allergic exposure.
Grooming includes:
- Tackling loose fur.
- Shaving the fur if required.
- Brushing the hair.
- Bathing the feline.
- Maintaining oral hygiene.
References
https://www.aafa.org/pet-dog-cat-allergies/
https://www.healthline.com/health/allergies/cats#treatment
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5891966/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5809771/
https://sciencedirect.com/science/article/pii/S2213219821011429
https://pubmed.ncbi.nlm.nih.gov/26220530/
