Horse allergy J 30.4

Frequent sensitization in people who have intensive contact with horses (e.g. riders, farmers). Clinical symptoms are allergic rhinoconjunctivitis, bronchial asthma, and exanthema. 16 allergens have been found in horse epithelia, horse hair, urine and saliva of horses. 4 allergens were analysed and identified (Equ c1-c4 -s.u. http://allergen.org). Diagnosis: Determination of specific IgE.

Relevant and identified allergens in Equus caballus (equine / domestic horse)

• Equ c 1: Lipocalin, major allergen from horse. Equ c 1 is found in high concentrations in saliva and coat, and in small amounts in urine. It has surface active properties. Equ c 1 is cross-reactive with allergens from dogs and cats!
• Equ c 2: Lipokalin, is recognized by about 50% of horse allergic persons.
• Equ c 3: Serum albumin 67- is responsible for cross-reactions with other animal albumin
• Equ c 4: Latherin, about 80% of horse allergy sufferers have a specific IgE against Equ c 4. This protein has pronounced surface-spreading, surfactant-like properties. It plays a role in sweat distribution and evaporation.
• Equ c 5: has been deleted (identical to Equ c 4) see http://allergen.org.

S.u. vertebrate allergens

In clinical tests it could be proven that "Curly horses" - horses with curles - show significantly weaker prick test reactions than the "standard horse". These results can also be clinically verified. "Curly horses" are therefore a suitable species for allergic riders to continue their sport.

This statement is put into perspective by recent studies (Zahradnik E et al. 2017).
Allergen tests (Equ c1/Equ c5) in harrow samples do not differ between curly horses and quarter horses.

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