Sweet Itch in Horses: Severe Insect Bite Hypersensitivity Management
Sweet itch (insect bite hypersensitivity, IBH) causes intense seasonal pruritus in sensitive horses and ponies, causing significant welfare suffering without appropriate management.
Key Facts
- An allergic reaction to Culicoides midge saliva in genetically predisposed horses
- Causes intense itching particularly of mane, tail, and belly, causing self-trauma
- Native and cob breeds are particularly susceptible; Icelandic horses have very high prevalence
- Prevention focuses on midge avoidance through stabling and protective rugs
- Immunotherapy is emerging as a potential long-term welfare management option
Welfare Considerations
Sweet itch welfare suffering is intense during midge season, typically April to October in the UK. Affected horses scratch relentlessly against fences, posts, and anything available, causing hair loss, skin damage, and open wounds. The chronic pruritus prevents normal rest and causes distress. Management requiring stabling during peak midge activity times (dawn and dusk) reduces exposure but restricts normal behavior. Sweet itch rugs covering the vulnerable body areas allow more normal turnout while reducing midge access. Antihistamines and corticosteroids provide relief during acute episodes but have limitations for long-term management.
What You Can Do
- Use sweet itch rugs providing full coverage from mane to tail and belly
- Stable affected horses during peak midge periods (dawn, dusk, calm evenings)
- Apply insect repellents regularly, paying particular attention to mane, tail, and belly
- Consider summer housing in well-screened facilities with fan systems that deter midges
- Work with your vet on immunotherapy options for severely affected horses