What Is Horse Allergy

Introduction 

Many people around the world suffer from horse allergies but unlike other pet allergies, this topic is not well known and discussed. This article will allow you to learn the types of horse allergies, what causes them and how they can be treated. 

What is horse allergy?

Horse allergy involves experiencing a reaction following exposure to substances found in a horse’s skin, saliva, and urine. This triggers an immune response which causes symptoms such as:

·       Runny nose 

·       Sneezing

·       Blocked nose

·       Itchy and watery eyes

·       Rashes and hives on the skin 

·       Swelling 

·       Shortness of breath

·       Asthma flare-ups

·       Anaphylaxis

It is important to understand horse allergies as symptoms can range from mild sneezing to severe breathing difficulties. Studies also show that horse allergies are more frequent than expected even in groups of people who live in urban areas with no direct exposure to horses.¹ Read on to gain a more in-depth understanding of horse allergies. 

What causes horse allergy?

Horse allergies are caused by proteins found in the horse’s blood. The proteins are part of the lipocalin family which is composed of many other allergens that cause animal and pet allergies.² The proteins are also in the horse’s saliva, urine, sweat and dander (shed skin cells). 

Some people’s immune system mistakes these for harmful substances and produce antibodies called IgE as a defence mechanism which sensitises you to the allergen. When you encounter the horse allergen again, you develop a reaction as your body releases histamine and other proteins which cause uncomfortable symptoms. 

Horse dander and horsehair can carry other allergens, including:

·      Pollen

·      Dust mites

·      Mould spores

·      Insect bites

These can cause allergic reactions in people with asthma, hay fever, or eczema (atopy). Pet dander alone can trigger symptoms or it’s the other allergens that they carry that are causing the reaction.  

Exposure to horse allergens

Direct contact with horses and their dander can cause sensitisation to the allergens in some people. Examples include horse riding or working in stables. Indirect exposure to horse allergens can be from going to work or school. People who have been in contact with horses can transfer dander and allergens on shoes and clothing to public places. Horse-derived materials can also be a source of allergen exposure in furniture and musical instruments. 

Many people who report no direct or indirect exposure to horses can still be sensitised and allergic to horse allergens. Horses and other pet dander can travel far distances and be present in urban homes as dust. Cross-reactions can also explain horse allergies as several other animal allergens such as cats and dogs are all lipocalins and share similar characteristics to horse allergens. Some people are predisposed to developing allergies due to genetics and younger children are also more likely to develop them. People with atopy or allergies to common pet dander should consider allergen testing before beginning an activity with direct contact with horses.¹

Signs and symptoms of horse allergy

Symptoms of horse allergy can range from mild to severe depending on how much you have been exposed to the allergen and how sensitive you are to the allergen. The more times you are exposed to the allergen, the more. You can get a reaction when visiting stables and horses or when you are around someone else who has been in contact with horses. The symptoms can develop immediately or occur later on, as horse dander can remain on your clothing. The allergen can cause symptoms when inhaled or touched.³

Symptoms include:

·      Runny, blocked or itchy nose

·      Itchy, red, watery eyes

·      Itchy throat

·      Sneezing

·      Pain, pressure and swelling around the face

·      Headache

Symptoms on your skin include:

·      Contact dermatitis

·      Redness

·      Itching

·      Swelling 

·      Rash

·      Hives

Horse allergy can trigger existing asthma or asthma-like symptoms:

·      Difficulty breathing or feeling short of breath

·      Wheezing

·      Coughing 

·      Tightness in your chest

Make sure to follow your treatment plan and inhaler instructions if you have severe asthma during an allergic reaction. 

Anaphylaxis

Severe horse allergy can cause anaphylaxis which is a life-threatening allergic reaction. Symptoms can occur very quickly after coming into contact with horse allergens.⁴

Anaphylaxis symptoms include:

·      Difficulty breathing

·      Breathing quickly

·      Swelling of your throat and tongue

·      Hoarse voice and tightness in your throat

·      Difficulty swallowing

·      Wheezing and noisy breathing

·      Coughing

·      Dizziness

·      Feeling faint or fainting

·      Confusion

·      Cold skin

·      Pale, blue or grey look to your lips or skin on the palms of your hands

These are severe symptoms, so it is important to seek emergency help by calling 999 immediately if you or someone else has these symptoms.⁵

Diagnosing and testing for horse allergy

If you notice symptoms of a horse allergy, you can contact your GP or health provider. This is especially important if you have other allergies and conditions such as asthma. They may refer you for allergy testing.

Skin prick test

A small amount of the allergen is put on your skin, usually the arm, and gently pricked or scratched. After 10-15 minutes, your skin will be examined and if you are allergic to the allergen, the skin in that area may be red, swollen, and itchy. The reactions will be measured and recorded. The reactions will disappear after 2-3 hours and a cream may be provided to stop any itchiness. Many different allergens can be tested in one go and the solutions used are diluted and unlikely to cause an allergic reaction. 

Blood tests

This measures the amount of IgE antibodies in a sample of your blood. It can be tested against single allergens or a mix of common allergens in a laboratory. The test might sometimes be referred to as a RAST test. IgE is produced in your body when you have allergies. The more IgE is found in the blood test, the more likely it is that you have an allergy to the allergen that is tested. 

A thin needle will be used to take a sample of blood usually from a vein in your arm. The needle might cause mild discomfort and a small bandage will be placed on your arm after a tube of blood is filled. The allergy blood test doesn’t have any serious risks but slight bruising and soreness can occur. These symptoms usually go away after 1-2 days. The results of the blood test can take a few days to come back and in some cases, you can still have symptoms even when no IgE is detected. A blood test is usually only preferred when you have a skin condition that makes a skin prick test unavailable.⁶

Management and treatment

When you have an allergy, it is important to have a management plan which you can make with your GP or healthcare provider. This is so you know how to prevent your symptoms and know what to do when an allergic reaction happens. 

Reducing exposure to horse allergens

Finding ways to control your exposure to horse allergens can help reduce symptoms:⁷

·      Avoid touching horses and visiting stables

·      If you know that you are likely to be exposed to horse allergens, taking an antihistamine beforehand and using your preventative asthma treatment can minimise symptoms 

·      Regularly groomed horses may help reduce allergen shedding

·      Washing hands after touching horses

·      Removing horse riding clothes before entering the home and showering can reduce allergens

·      Wash horse riding clothes and gear regularly

·      Using an air purifier, may help reduce airborne allergies inside the home

·      Clean dust with a wet cloth can help reduce horse dander in dust

·      Vacuum carpets with high-efficiency particulate air filter vacuums 

Hypoallergenic horse breeds

Breeds such as Curly Horses and Shetland ponies are thought to be hypoallergenic and found to cause fewer symptoms when riding. And tests show female horses produce less allergens compared to male horses. However, dander from all tested breeds contained allergens so no breed is fully non-allergic, and more research is needed to test for hypoallergenic horses.⁸ 

Medicines 

Depending on the type and severity of your symptoms, medications can be suggested by a Health Professional. Many of these treatments reduce the symptoms and effects of the allergy to horses and not the allergy itself. Medications include:

·      Antihistamines (non-sedating)

·      Allergen barrier balm

·      Antihistamine nasal sprays

·      Eye drops

·      Steroid tablets and creams

·      Asthma inhalers

·      Adrenaline auto-injectors

Immunotherapy 

Moderate to severe horse allergies or reactions not controlled by anti-allergy medications can require allergen-specific immunotherapy. It can be referred to as desensitisation. This works by giving your body small, increasing amounts of the allergen over some time by injection. As this is done in a controlled medical setting it is easy to monitor reactions and minimise risk. Over time the body’s reaction to the allergen is reduced as it gets used to it. New applications of this technique are being researched so more ways to reduce horse allergies can be developed.⁹

Summary

Living with allergies can be difficult and for some people, it can affect their daily activities. Horse allergies can occur in anyone even when you’re not in direct contact with horses so if you have symptoms, contact your healthcare provider. Horse allergies can cause many symptoms ranging from mild to severe, so it is important to have a management plan in place. With treatment and techniques to limited exposure, the effect on your quality of life can be minimised.