Ringworm in Cats

Symptoms, Causes and Treatment of Ringworm in Cats


9 February 2022

This article is written by Pet Circle Veterinarian, Dr Carla Paszkowski BVSc.


Ringworm (feline dermatophytosis) is one of the most common causes of skin infection in cats all over the world. Causing itchy, scaley, red lesions on most mammals (including humans), this irritating infection is usually worst in the young or immunocompromised. Kittens, children, and allergy sufferers (both feline and human) are usually the worst affected by ringworm. Thankfully, the issue is easily treated and doesn't cause serious disease unless a secondary germ takes advantage of the infection.

Is ringworm a worm? Despite its name, Ringworm is not a worm! Ringworm is actually caused by a fungus. (Perhaps it would be better named 'Ringus'!) The only thing it has to do with rings is the typical circular area of dry, scaley rash that usually appears on the animal.

Jump to a section:
1. What is Ringworm?
- How do cats get ringworm?
- Cat ringworm in humans
2. Symptoms of Ringworm in Cats
3. How to Treat Ringworm in Cats
- Does Advocate treat ringworm in cats?
- Product list - best ringworm treatments for cat available online

What is Ringworm?

Despite the name, Ringworm is not actually a 'worm', but a fungus. (Perhaps a more fitting name would be 'Ringus'!). When we talk about 'ringworm', we are usually referring to the infection caused by the fungus, rather than the fungal organism itself.

The fungal pathogen responsible for ringworm is a commensal organism found on healthy skin, but only causes disease when it grows in too great a quantity, or if the skin or immune system is comprimised and can't fight it off. The pathogen that causes ringworm is also responsible for 'athlete's foot'.

In cats, about 98% of ringworm cases are caused by a species of fungus called Microsporum canis, however it may be caused by any species of Microsporum, Nannizzia, or Trichophyton fungi.2 These types of fungi are invisible to the naked eye, but looks a little like this under a microscope:

Source: James Scott, University of Toronto, via Medmyco at English Wikipedia

How do cats get ringworm?

The Ringworm fungi spread easily in the environment. It is primarily spread via contact with an infected host (be it feline, human, or another mammal such as a dog) or by touching contaminated objects like furniture, towels or grooming tools. Broken hairs that contain the fungal spores are a common source of spreading ringworm. Spores may survive in the environment for up to a year.1

As with many diseases, direct contact does not always result in infection. The development of lesions depends on host factors - particularly age, immune system health, skin quality, hygeine, and nutrition. This is why the disease is commonly seen in kittens, stressed cats, pregnant cats, or those with skin allergies. Interestingly, Persian cats may be predisposed to developing ringworm. It is unclear, however, whether FIV-infected cats are more susceptible to ringworm.4 Likewise, children, pregnant women, the elderly, and immunocompromised people (such as those with HIV or eczema) are more commonly affected.

Where did my kitten catch ringworm? As stated previously, the Ringworm fungus is a commensal organism that grows on the skin naturally, so your kitten may be exposed anywhere or from anywone. However, kittens are often exposed to larger quantities of the fungus in environments such as a shelter, cattery, pet store or breeder - which may concurrently be a stressful environment for the kitten and therefore compromises their already fragile immune system.

Cat ringworm in humans?

Photo credit: @peopleforanimalwellness

Ringworm is transmissible between pets and humans. While cats can transmit ringworm to humans, in fact, many cats are actually infected by children in the household who have been infected at school or day care. (And unfortunately, often the cat is blamed for passing it to the child, rather than the other way around!)

If you or your child has been diagnosed with ringworm infection, don't panic - the disease is fairly easy to treat. (See our treatment section below)! You certainly shouldn't get rid of your cat or remove them from your house temporarily - this will only stress your cat and therefore make them less likely to recover. Remember that a strong immune system can usually fight off ringworm fungus on its own, so never under estimate the power of good nutrition, rest, cat probiotics, and Omega fatty acids (such as fish oil) for cats alongside medical and environmental treatment!

Symptoms of Ringworm in Cats

Photo credit: Colorado Animal Rescue

Symptoms of Ringworm in Cats

  • Inflamed, ring-like lesions on the skin
  • Itchy skin
  • Scaly, dry appearance to the skin with dandruff
  • Hairless patches
  • Crusty lesions - particularly around the nose, face, or ears

Ringworm usually produces red, inflamed, ring-like lesions with a scabby or bald centre, or thumbprint-shaped scabby lesions. However ringworm can also present as generalised, dry, scaly, or sparsely haired skin. In cats, it can affect any part of the body but is particularly common over the head and face. In humans, lesions usually present as ring-like or thumbprint-shaped red lesions. In both cats and humans, lesions may or may not be itchy.

How to tell if my cat has ringworm? Ringworm needs to be diagnosed by a vet before choosing a treatment. This is particularly important because some bacterial infections and parasites can appear similar to ringworm but require a different treatment. To diagnose ringworm, your vet may do a microscope examination of your pet's skin scraping or fur, and they may also use a Wood's Lamp to observe the fur for flourescence. A Wood's lamp is a special UVA-A light and infected hairs can fluoresce ('light up') under its light. While some ringworm fungal species may not flouresce, a Wood's Lamp can be useful because Microsporum canis will always flouresce and this is the main clinically relevant fluorescing veterinary dermatophyte.3

Flourescence of ringworm fungus under a Wood's Lamp.

Photo credit: @canine_myofascial_therapy

Treatment of Ringworm in Cats

Although ringworm in most healthy animals will clear up on its own, treatment is recommended due to the contagious nature of the disease and its ability to spread to humans.5 A combination of topical and environmental treatment is ideal - and oral medication may be required in certain circumstances.

How To Get Rid of Ringowrm in Cats

1. Clean the environment

Ringworm can persist in your home environment for months or even a year. Getting rid of it requires extensive sterilisiation and cleaning of your home and all bedding. Environmental decontamination involves cleaning to remove as much hair and debris as possible, and then disinfecting surfaces to kill any remaining spores.

How to get rid of ringworm in your home:

  • Remove hairs. Use electrostatic wipes, lint rollers, or a strong vacuum to remove hairs from furniture, carpet, bedding, clothing, and other surfaces.
  • Disinfect surfaces. Sodium hypochlorite (chlorine bleach) diluted 1:10 and 1:32 is suggested as it has good antifungal activity.
  • Clean your carpets. You may wish to use a carpet shampoo or a carpet disinfectant - however keep your pets off the carpet until they are completely dry as wetting carpets can cause sporulation.6
  • Launder sheets and clothes. Use a hot wash to clean any exposed sheets or clothing and spray the machine after use with a diluted bleach.

2. Treat your cat's ringworm

To clear up the infection on your cat, ringworm requires topical treatments. Ringworm can be killed by repeatedly soaking the area with iodine-based products such as Troy Iodin Spray or Betadine - however Betadine should be diluted 1:5 with water before applying to your cat's skin. Ringworm should also be treated with an antifungal lotion containing medication such as miconazole (such as Fungafite) or iodine (like Quit Itch Lotion) as well as 2-3 weeks of daily washing with an antifungal shampoo containing miconazole such as Malaseb. View more about these products below.

It's important to keep in mind that ringworm may require weeks, or even months, of strict treatment. Never stop treatment before your vet has given you the 'OK'!

3. Additional Skin and Immunity Support

Remember - a healthy immune system and skin barrier will be able to fight off ringworm by itself with time, so whatever you can do to help support your cat's skin health is beneficial. This might include supplementing with Omega Fatty Acids (my top recommendation for cats is Megaderm Nutritional Supplement), introducing a cat probiotic (my top recommendation is Vetafarm Synbiotic Meal Topper), or swapping to a premium quality pet food if you aren't already feeding one.

4. Address Stress and Anxiety

Tying in with extra immune support as outlined above, it's vital to reduce stress for your kitty while they recover. Cats are extremely prone to stress - in fact any change at home such as moving house, a new pet, or visitors to the home can push cats into stress-induced cystitis! - and every health issue can worsen if your cat is suffering from anxiety. The best treatment for anxiety in cats does vary depending on the situation, but a good place to start is by allowing your cat plenty of safe, secluded and quiet hiding spots, investing in a Feliway Diffuser, and following the steps in my article below:

5. Treat your family if you have lesions

. If you or your family members have lesions, it's best to seek the advice of your doctor - and get a proper diagnosis to ensure they are actually ringworm lesions. The typical treatment for humans is very similar to cats; ie, topical creams and iodine or miconazole-based washes combined with environmental cleaning and good hygeine. As with cats, it can help to support your immune system and skin barrier with good nutrition (particularly Vitamin E, C, D, Omega Fatty Acids, probiotics, and plenty of water!)

Does Advocate treat ringworm in cats?

No! Advocate does not treat ringworm and is completely ineffective against it. This is because Advocate is an anti-parasite treatment that protects cats against fleas, intestinal worms, and heartworm - and because ringworm is caused by a fungus (NOT a worm!), Advocate has no effect. View the best products for ringworm below.

The Best Ringworm Treatments for Cats Compared

Product Type of product Active Ingredient Directions

Fungafite

Fungafite Ointment

Ointment 20mg/g Miconozole

Apply a thin layer sufficient to cover the infected site and a small surrounding area of skin once daily for 2 - 4 weeks. Severe cases may require prolonged treatment. Continue for 1 - 2 weeks past resolution.

Malaseb

Malaseb Shampoo

Shampoo Miconazole Nitrate 2% Chlorhexidine Gluconate 2%

Apply and lather over the entire body, allowing 10 minutes of contact time. Rinse completely with water. Do not allow the animal to lick while bathing to prevent ingestion. Repeat twice weekly until symptoms subside, then weekly, or as directed by your veterinarian.

Aristopet Stop Itch

Aristopet Stop Itch

Ointment / Can be made into a shampoo with dilution 15g/L Povidone-iodine, 6g/L Iodophor

Dilute 1 part of Stop-itch to 20 parts of warm water and rub well into the coat and allow the foam to remain for at least 5 minutes. Rinse, dry, and then liberally apply undiluted Stop-Itch to infected and surrounding areas. Wipe off excess from coats of cats.

Quit Itch

Quit Itch

Ointment / Can be made into a shampoo with dilution 15g/L Povidone Iodine, 6g/L Iodophor

Use a solution of 1 part Quit-Itch to 20 parts warm water. Rub well into the coat and allow the foam to remain for 5 minutes. Rinse, dry and apply undiluted Quit-Itch to infected and surrounding areas.

Shop All Ringworm Treatments for Cats


Further Reading

How to get rid of fleas on your cat once and for all

Know Your Parasites: Fleas, Ticks, and Worms

Complete Guide to Cat Flea and Worming Treatments

What is feline acne?

Yeast infections in pets

Can Indoor Cats Get Fleas?

Can You Flush Cat Litter?

References

1. Frymus T, Gruffydd-Jones T, Pennisi MG, Addie D, Belák S, Boucraut-Baralon C, Egberink H, Hartmann K, Hosie MJ, Lloret A, Lutz H, Marsilio F, Möstl K, Radford AD, Thiry E, Truyen U, Horzinek MC. Dermatophytosis in cats: ABCD guidelines on prevention and management. J Feline Med Surg. 2013 Jul;15(7):598-604. doi: 10.1177/1098612X13489222. PMID: 23813824.

2. Boehm TMSA, Mueller RS. Dermatophytosis in dogs and cats - an update. Tierarztl Prax Ausg K Kleintiere Heimtiere. 2019 Aug;47(4):257-268. English, German. doi: 10.1055/a-0969-1446. Epub 2019 Aug 21. PMID: 31434126.

3. Moriello KA, Coyner K, Paterson S, Mignon B. Diagnosis and treatment of dermatophytosis in dogs and cats: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology. Vet Dermatol, June 2017; 28(3): 266-e68.

4. Barlough J, Timoney J, Hagan W, Bruner D, Scott F, Gillespie J (1988). Hagan and Bruner's Microbiology and Infectious Diseases of Domestic Animals: With Reference to Etiology, Epizootiology, Pathogenesis, Immunity, Diagnosis, and Antimicrobial Susceptibility. United Kingdom: Comstock Pub. Associates.

5. Miller W H, Griffin C E, Campbell K L: Fungal and algal skin diseases. Muller and Kirk’s Small Animal Dermatology, 7th ed. Saunders Elsevier, St. Louis 2013 pp. 479-619.

6. Moriello KA: Decontamination of carpet exposed to Microsporum canis hairs and spores.. J Fel Med Surg 2017 Vol 19 (4) pp. 4.