From  Your Horse  -  Jan. 2015

Preventing rain scald

As we head into winter, a number of skin diseases will begin to rear their ugly heads, rain scald among them. Vet Nancy Homewood tells us more about the condition

Rain scald commonly affects the back and can be extremely painful for the horse


NANCY HOMEWOOD   -   BVetMed MRCVS is a vet from Hook Norton Veterinary Group, which is a member of XLEquine. She has a special interest in anaesthesia, internal medicine and wound management. Visit www.xlequine. for more information.

Rain scald, also known as rain rot, is a skin condition in horses caused by the bacteria Dermatophilus congolensis. It's always present in your horse's skin, but excess moisture and humidity allow it to penetrate and multiply, causing infection. Commonly found along the back, neck and head, clinical signs include clumps of matted hair with an egg-shaped scab underneath. The under surface of the scab will often have hair roots protruding through. These scabs can be painful to remove and, if in an area where equipment is used, e.g. under the saddle, it's advisable not to ride until the condition has disappeared. It can be diagnosed from sight, but your vet may want to pluck a hair, take a skin scrape or a swab to certify the disease.

How to treat rain scald effectively

If left untreated, recovery from rain scald can take between three to six weeks after diagnosis, provided appropriate control measures are put in place. The use of a topical treatment on the area will speed up healing time. To help remove the scabs and treat the underlying skin lesions, washes containing chlorhexidine and povidone-iodine can be used. Topical antibacterial creams can help and, in severe cases, general antibiotics maybe required.

Grooming brushes should be washed in disinfectant and you should avoid sharing tack and

equipment with other horses to help prevent it spreading.

Rain scald is not a condition that horses develop immunity to so your horse may surfer from it again in the future if the correct management conditions aren't put in place. If you think your horse has rain scald, it's best to contact your vet as they can advise on the most appropriate treatment.


Keeping a close eye on your horse's skin will help you to quickly identify when there's a problem, so be sure to remove his rugs on a daily basis - even if your horse is turned out 24/7 - so that you're able to check him over thoroughly.

Stop it taking hold

Good management is the easiest and most effective way to prevent rain scald from happening in the first place. In wet weather, make sure your horse stays dry when turned out by rugging him up, and provide a clean, dry stable for him to come into in bad weather. If he does get caught in a downpour, make sure you thoroughly dry him before placing a dry rug on him. Rain scald can be contagious between horses through direct contact or by sharing tack, rugs and other gear, so make sure all equipment is kept separate.

Frequently asked questions

I've treated my horse but now another horse on the yard is infected, what should I do? 

When treating rain scald, treat ail affected horses. If a chronic carrier is left untreated they'll continue to be a source of infection.

How important is it to keep my horse dry? Bad weather is making it almost impossible.

It's vital your horse stays dry as repeated exposure to wet weather will decrease the success of treatment. As well as using a topical treatment, appropriate rugging and shelter are vital.

I've treated my horse but he's not improving. Why?

Special care must be taken for elderly, immunosuppressed horses or those diagnosed with Cushing's disease. If your horse has an underlying disease he may not respond to treatment so advice from your vet should be Sought.