Guide to sweet itch

What is sweet itch?
Sweet itch or Culicoides hypersensitivity is a skin disease affecting horses that is caused by an allergic reaction to biting midges. It is a seasonal, recurrent condition occurring in the warmer months.

What are the signs?
Symptoms can include severe pruritus (itching), hair loss, skin thickening and flaky skin. Typically sweet itch affects the mane and base of the tail. However, it can extend to the face, ears, neck, belly and shoulders. The signs include:
  • Mild to severe itching and rubbing along the mane, back and tail. 
  • Loss of tail and mane hair.
  • Bald patches on the skin.
  • Sore, open, broken skin, which can bleed. 
  • Itching along the legs and under the belly. 
  • Some affected horses can become irritated by constant itchiness, swishing their tails vigorously, rolling frequently and attempting to scratch at anything within reach. 

What measures can I take to protect my horse?
  • Minimise midge attacks by avoiding turnout during dawn and dusk, when biting midges are at their worst.  Ensure stabling and turnout is more than half a mile from static water where midges breed, and away from woods, trees and high hedges where midges congregate. Also avoid boggy, marshy fields and move susceptible horses to open, breezy fields. 
  • Stable your horse at dusk and dawn when midge feeding is at its peak. Other preventative measures include using ultrafine netting over stable doors and windows, spraying housing and screens with insecticides, and installing fans in stables (midges are very weak fliers). 
  • Keep your horse’s skin protected with fly sheets and masks. Fly rugs are available in a variety of styles and offer full coverage, including neck and belly protection, while a face mask can protect the horse’s sensitive ears and eyes. 
  • Regularly apply an effective insect repellent; check that the ingredients are safe and do not contain FEI-banned substances.  

How to minimise the allergic reaction?
If your horse is affected by sweet itch, seek veterinary advice – it is a lifelong condition that needs careful management.
A combination of preventative measures and taking appropriate action/treatment as soon as any signs develop will help to manage the problem. 
Soothing lotions and sprays can help to provide a cool feeling to areas that are warm and uncomfortable. Look for products that carry a BETA NOPS logo, which is reassurance that they have been adequately tested and are safe for use on horses.

Photo: Getty Images