What is rain rot in horses

What is Rain Rot in Horses? How to Identify and Solutions

After a good play in the rain, you might see some lost hairs and patches on the coat of your horse. Here you will learn what rain rot is in horses? How to identify and solutions.

The coat is no longer glowing, and rubbing the dry skin can be irritating. If you see these, your horse is likely to be suffering from a skin disease, especially the bacterium Dermatophilus congolensis, commonly called rain rot.

What is Rain Rot?

Rainwater and any other water trigger rain rot; however, this doesn’t mean that the horse is at risk of getting infected when rained on. The problem is if the water remains on the coat for an extended period, it will attract bacteria that carry the infection into the horses’ skin. The bacteria look for weak spots that may penetrate through insect bites and open wounds. 

Damp water on the skin compromises the toughness of the skin. It’s a way for the infection to spread faster from the skin to other body parts if rubbed. If you lash the organism, it can get to another animal’s body.

Besides rain, climates with humidity and areas with precipitation can also trigger rain rot infection. If the hair loses and the skin gets dry, the disease is at early stages and isn’t severe. But if you notice some soft scabs and clumps that are hard to remove, it’s a sign of severeness and needs a vet check.

How to Identify Rain Rot in Horses

Dermatophilus congolensis is the bacteria behind the rain rot infection. After it penetrates the skin, it results in lesions on the horse’s coat. They appear like bumps and have a bunch of hairs on the scabs. 

The scabs are challenging to remove, and if done, they leave bald patches on the skin. Sometimes they may become large and affect the skin layers. In this case, it’s not appropriate to ride on such a horse until it heals. 

Rain rot may also occur in other parts of the horses’ body, like the face, belly, and legs. Therefore, you should examine your horse regularly. You may touch the skin and feel for the bumps during the rainy season. It may be challenging to analyze the coat by just observing. Also, the infection is not itchy but gets painful when touched.

Rain rot affects all breeds, but those with a poor immune status, light coat colors, and insect bites, have high chances of getting the infections-other factors like high rainfall and humidity nurture the bacteria. Therefore, horse owners should check that the horses stay in the regions that won’t compromise the skin.

What Causes Rain Rot in Horses

Rainwater is the leading cause of rain rot. However, if your horse sweats regularly, some of it may be trapped on the tack and saddles, increasing the chances of getting the dermatophilosis bacteria. 

Retired or idle horses are prone to rain rot because they dont get groomed more often. Therefore, their coats may carry moisture that is not dried regularly.

Rain rot also affects horses that have low immunity. Existing skin diseases, metabolic or immunologic problems, or other ailments that compromise immunity or the skin make the bacteria more fertile.


Whether your horse has a rain rot infection or not, it’s better to take the necessary measures to prevent it from getting the disease or spreading to the other horses. Otherwise, it’s costly to identify the cause of reinfection.

Ensure Your Horse is Dry

Rain rot affects a complicated skin layer. Prolonged water in the skin may cause it to crack hence paving the way for the bacteria. As the horse owner, ensure you keep your horse in a safe stable where rain can’t reach it. 

During hot seasons, keep your horse in shades to prevent sweating. You might consider installing cooling devices in the stable to keep it cool. 

Don’t blanket your horse after untacking, as this ensures that any sweat around the coat on tacks is dry. Also, don’t use dense blankets during the hot season to avoid too much sweat.

Use Waterproof Blankets

Maintain your horses’ blankets. Clean them after every season, even if it still looks clean. Invest in waterproof blankets if the horse has to graze in the rain.

Daily Grooming

Grooming your horse frequently prevents rain rot. The bacteria can easily rest on dirty coats. While grooming, ensure the tools are clean to prevent the spread. 

Also, keep your horse away from biting insects since they make way for the bacteria. You can either make your horse put on a fly sheet or spray it with insecticide.

Use gloves when grooming an infected horse. Cover open wounds or cuts to prevent yourself from containing the infection. Ensure you clean your hands thoroughly after grooming.


Most horse skin diseases don’t affect the health of a horse. But for those infections that get beneath the skin, such as rain rot, may tamper with your horses’ wellbeing. 

Fortunately, it is easy to diagnose, treat and heal. You can treat the infection yourself, but you need to consult a vet. 

Here is how to treat rain rot:

Scab Removal

A horse with rain rot usually has lesions and scabs on its skin that resemble ringworm symptoms. The scabs show that the bacteria are active, making it ooze after some time. 

Scab removal makes your horse uncomfortable and may be painful. Therefore, you need to do it most gently. Fortunately, some tools help with the process. 

Hydrogel is an excellent method to remove the scabs. It entails cleaning and protecting the infected part. It also helps in quick healing.

Brushing is also another way of getting rid of the scabs. Ensure the bristles are smooth and robust. Brushing will loosen the scabs to be easier to remove. Sometimes they can be so loose that they fall off. 

Making them fall off is better than pulling them directly. If the scab is still sticky, you may apply an ointment recommended by the vet and remove it later.

Cleaning the Infected Part

Before cleaning, you have to remove the scabs to uncover the skin. With that, it will be easier to clean the infected part. 

Horse experts suggest cleaning the horse using antibacterial and antimicrobial shampoos. The antibacterial shampoo contains chemicals that kill a high percentage of active bacteria. You may consider washing the whole body since the bacteria might have spread to the other parts. Afterward, use a preferred horse shampoo. Ensure the horse skin is completely dry.

After the horse is dry, use an antimicrobial spray to prevent the bacteria from spreading. Spray the horse daily until the infection subsides. 

Bathe your infected horse at least once or twice a week. Bathing isn’t a complete treatment, and too much of it may worsen the condition.

Rain Rot Parental Antibiotics

Applying antibiotics to horses with severe infections with topical treatments makes it more effective. 

Isolation and Disposition

Isolate your infected horse or be keen that it doesn’t contact the healthy ones. Rain rot is contagious, and since the bacteria is still active, it may easily infect all horses.

Please dispose of the scabs in an enclosed bin or burn them to prevent reinfection. Also, clean the treatment scene to get rid of small pieces of scalps that can be difficult to identify. 

Ensure you isolate the tools for treatment and disinfect all the equipment that the infected horse has used.

Remember, rain rot can affect you too. Be careful when treating an infected horse by wearing the proper equipment. Clean your hands thoroughly before getting into contact with another horse or its equipment. 

Home Remedies Treatment

Fortunately, there are home remedies that vets approved to treat rain rot. Here are some of the treatments:

#1 Remedy


  • Baby or mineral oil – 16 ounce
  • USP hydrogen peroxide – 16 ounce
  • Iodine – 5 ounce


  • Add all the supplies to a bucket and mix evenly. Keep adjusting the measurements since too much hydrogen peroxide may explode the mix.
  • Apply it to the infected area and the surrounding parts.
  • Allow it to stay on the skin overnight, which will soften the scabs and make them easy to pull. The baby or mineral oil smoothens and lubricates the skin. The iodine weakens the bacteria.
  • Wash it thoroughly using shampoo
  • Allow your horse to dry.

#2 Remedy

This remedy entails similar supplies and prescriptions to the first one. You can add Listerine to make it more effective on the skin. This remedy is suitable after treatment since it’s so harsh that no reinfection can happen in the future. However, Listerine contains isopropyl alcohol that might be harsh on the hair and skin of your horse.

#3 Remedy

If both remedies mentioned become ineffective, you could go for this option. It entails Betadine scrub and ointments. Use effective creams that vets recommend, such as Nystatin Anti-Fungal, Triple Antibiotic, and Hydrocortisone. 


  • Mix all the ointments. It’s more effective if combined.
  • Wash the infected part thoroughly using Betadine scrub
  • Apply the cream daily until the sores heal

Though this remedy works, try to minimize anti-fungal ointments since rain rot infection is due to bacteria but not fungus.

Misconceptions about Rain Rot in Horses 

  • Rain rot only affects horses that have been in the rain.

Rain rot can affect both a blanketed and a rained-on horse. A non-waterproof blanket may retain some moisture that, if prolonged it may nurture the rain rot bacteria. Use waterproof blankets and allow air to dry up any trapped water.

  • You can treat rain rot by removing the scabs then grooming the horse.

Scab removal and grooming are one of the treatment procedures. Horses have a thick coat that blocks the bacteria from penetrating. However, wounds and insect bites make the penetration easier. They will form scabs that you can easily remove.

After scab removal, you leave the horse with unprotected patches, which have higher chances of reinfection. Therefore, you need to do continuous treatment until the sores heal entirely, allowing hair to grow back.

Final Verdict

Though rain rot is a common infection, it doesn’t irritate the horse nor threaten its life. However, if the disease gets severe, it may lead to a worse health condition. The treatment is easy; washing the infected parts or the whole body using shampoo and applying ointments that quickens the healing process. If the infection gets extreme, use antibiotics or consult your vet.