How Long To Quarantine Cat With Ringworm?

How Long To Quarantine Cat With Ringworm?

Ringworm is a skin fungal infection that is prevalent among kittens and long-haired cats but it can affect cats of any breed or age. This skin condition can spread to humans especially those that are immunocompromised or people that have impaired immune systems. It is not caused by a worm but a group of fungi called dermatophytes with a medical name of dermatophytosis.

How long to quarantine cat with ringworm?

If your cat has ringworm she should be quarantined for 14 to 28 days since it is a very contagious and zoonotic disease, meaning it can be transferred from cats to humans. You should give oral antifungal medication to your cat during this period and at least four medicated baths. You may allow your cat access to areas like an uncarpeted room that is easily cleaned but she should be prevented from roaming the home freely. 

Nevertheless, this quarantine period may be extended if your cat still has ringworm outbreaks. Treatment should be continued and your cat should be closely monitored to avoid the further prevalence of this skin problem. Make sure to wear gloves and protective clothing when handling your cat during the quarantine period. 

Ringworm in Cats:  Symptoms, diagnosis and treatment 

Microsporum canis, the species of ringworm that affects cats is a zoophilic fungus which means it is well-adapted to cats and it may live on their fur and skin without any clinical signs of the condition. Two less common fungal species, Microsporum gypseum and Trichophyton spp, may also cause ringworm in cats. 

Cats that are prone to ringworm infection are those with concurrent diseases, poor nutrition, stress and young age. Other factors may include intake of drugs that suppress the immune system and overcrowding in a multi-cat household or animal shelters and catteries. Long-haired cats that are less efficient groomers are also at high risk since grooming is one way that can effectively remove ringworm spores from the fur. 


The typical signs of ringworm in cats include one or multiple areas of patchy hair loss accompanied by mild to moderate crusting. However, this may vary from one cat to another. 

Here are other symptoms of ringworm in cats:

  • pruritus or itchy skin – some cats may have mild itchiness while others may self-mutilate due to extreme itchiness
  • hair loss- it may be subtle or extensive and may be symmetrical or asymmetrical pattern
  • scaling and crusting – some cats may have mild scaling while for others it may be severe
  • ring-like lesions 
  • circular and thickened skin patches that are sore and crusty 
  • blackheads – these are usually seen on the chin of younger cats 
  • hyperpigmentation or darkening of the skin 
  • nail infections – some cats may have crusty or greasy nail infections 
  • redness in the areas with hair loss 
  • overgrooming – this is observed among cats with symmetrical hair loss 
  • unilateral or bilateral itchiness of the ears 


If you suspect that your cat has ringworm, bring her to the vet for a thorough checkup. Your vet will most likely perform a fungal culture to confirm what skin condition is affecting your cat.  He may pluck the fur from affected areas with a sterile hemostat and place it on a fungal culture medium. Usually, vets may use a dermatophyte test medium as it contains a color indicator which turns the medium into red when there is ringworm presence.  

Vets use a Woods Lamp as a screening tool to identify infected hairs for better samples for the fungal culture and strains of the fungus may glow apple green or yellow-green under the lamp. The fluorescence is caused by a metabolite that the growing fungi secrete onto the fur. 


Common treatment methods for ringworm in cats include anti-fungal medication along with an anti-fungal shampoo. Topical products such as Miconazole may also be effective.  Cats with ringworm should be bathed at least twice weekly with antifungal shampoo like Malaseb and the contact time with the cat’s fur should be at least 10 minutes. However, topical ointments and creams are not generally recommended since they are sticky. 

Vets rely more on systemic therapy with oral medication but these drugs should not be used in kittens less than eight weeks old. Medications that are known to be effective against ringworm include ketaconazole, terbinafine and itraconazole.  After four weeks of treatment,  infected cats should be re-examined through a Wood’s lamp exam and infected hairs should be removed. During every re-examination, a fungal culture must be performed until such time that three negative cultures are achieved. 

Aside from oral medication, your pet should be placed in a room that is easy to clean and should be prevented from roaming the whole house freely. This is to avoid fungal spores from spreading throughout the home. If you have a long-haired cat, your vet may recommend clipping or trimming her fur and washing her with anti-fungal shampoo. 

Home decontamination may also be done with the help of pet-friendly chemical disinfectants to remove infected fur in floors, furniture and carpets. Cat toys and beddings that are hard to clean should be thrown away to avoid re-infection. Decontamination is essential since fungal spores may live in your home for more than a year and your cat may become infected again. If you have other pets, consult your vet about treating them also. 

Here are some decontamination protocols to prevent the spread of fungal spores:

  • cat beds and blankets should be washed with hot water and bleach daily
  • bathrooms and smooth surfaces should be disinfected with a bleach solution of one part bleach and nine parts water 
  • discard cat rugs, blankets, collars, brushes and fabric toys 
  • throw away objects used by your cat that are hard to clean 
  • swap your used vacuum cleaner with a new one that has easy-to-clean hose attachments 
  • remove and clean all drapes, clean heating ducts and vent plates and install house dust filters to keep the fungal spores from the heating ducts 
  • place a fan in the window to draw air out of the room 
  • vacuum all room surfaces 
  • dust ledges and surfaces with Swiffer electrostatic cloth 
  • apply disinfectant on all surfaces around the home 

If treated properly and by diligently following decontamination protocols, your cat is unlikely to become infected again. If you are planning to add cats to your household, make sure they are screened for ringworm and bathed with medicated shampoo while awaiting the fungal culture results.  

Final thoughts 

Being infected with ringworm is daunting and very discomforting for your cat as it causes fur loss, extreme itchiness and other skin issues. It is highly treatable as long as you follow proper treatment procedures and decontamination protocols. Ringworm in cats is contagious and may infect humans so extreme caution should be taken as well as guidance from your vet. 

Image: / Andrii Atanov