Moderate

Summer sores

Summer sores is cutaneous habronemiasis — a fly-borne wound infestation by Habronema or Draschia larvae. It is not ordinary proud flesh (exuberant granulation tissue) and not a tumour (sarcoid). A photograph cannot diagnose summer sores. A still cannot tell summer sore from proud flesh, sarcoid, or granulation. Diagnosis is a vet exam, often a biopsy. The skin scan is a first look at the wound, not a verdict that your horse has summer sores, and there is no summer-sores scanner.

Symptoms to watch for

A non-healing wound that stays raw, moist, or ulcerated — often on a lower leg, the eye margin, or the urethral process

Pink, fleshy, or granulomatous tissue that looks like proud flesh but does not settle

Yellow or white gritty specks in the wound — a clue some people associate with larvae, not a photo diagnosis

Intense itching; the horse may rub, bite, or stamp at the wound

A wound that worsens in fly season and may quiet in winter — season is a clue, not a diagnosis

A change in size or surface of the wound is a reason to book a vet, not a photo verdict

Common causes

Cutaneous habronemiasis — fly-deposited Habronema or Draschia larvae in a wound or on moist skin, not ordinary proud flesh and not a tumour
House flies or stable flies that carry larvae from manure to a wound, the eye, or the penis — the fly is a clue, not a diagnosis
An open lower-leg wound, a moist eye margin, or a urethral process that larvae can colonise — location is a clue, not a diagnosis
Individual susceptibility and fly pressure; some horses get summer sores more than once
Not ordinary proud flesh (exuberant granulation), not sarcoid (a BPV tumour), and not simple granulation — those can look the same and still need a vet

Prevention

Watch non-healing wounds in fly season, and book a vet rather than waiting for a photo guess
Keep wounds clean and flies down — manure management and fly control reduce the chance larvae reach a wound
Do not cut, burn, or apply a caustic from a web article or a scan result
Do not treat a photo, a wound, or a scan result as a diagnosis
Skin photos can help you and your vet track the wound over time — they do not confirm or rule out summer sores, and they cannot tell summer sore from proud flesh, sarcoid, or granulation

What to do

1
Book a vet visit for a non-healing wound that looks like proud flesh, especially in fly season. Diagnosis is a vet exam, often a biopsy — not a photograph.
2
Photograph the wound in good light and keep it on the horse's record so you and the vet can see change over time.
3
Do not cut, burn, ligate, or apply a caustic cream from a photo guess — a still cannot tell summer sore from proud flesh, sarcoid, or granulation.
4
Use a skin scan only as a first look at the wound to share, not as a summer-sores test. There is no summer-sores scanner.
5
If summer sores (cutaneous habronemiasis) is confirmed, follow the plan your vet prescribes — that may include deworming, wound care, fly control, or further treatment. Do not start a treatment protocol from a photo.
6
Keep the vet on the same page. Share what you see; do not treat a photo as a verdict.

When to call the vet

Pick up the phone if…

Schedule a vet visit if a wound will not heal, looks like proud flesh, itches intensely, or worsens in fly season. Call sooner if the wound is spreading, involving the eye or penis, or the horse is dull or off feed. A photograph cannot diagnose summer sores. A still cannot tell summer sore from proud flesh, sarcoid, or granulation. Diagnosis is a vet exam, often a biopsy. Summer sores is cutaneous habronemiasis — fly-borne Habronema or Draschia larvae, not ordinary proud flesh and not a tumour. The skin scan is a first look at the wound, not a verdict, and there is no summer-sores scanner.

Check the skin before it spreads

Scan the skin in HorseCare. 5 free scans this month, then Pro.

Scan the skin

5 free scans this month, then Pro. Scans run in the HorseCare app.

Educational content only. Not a substitute for veterinary advice.