A Short Guide to Understanding Ringworm: Symptoms, Diagnosis, and Treatment

What is Ringworm?

Ringworm is a highly contagious fungal infection that affects the surface of the skin. These fungi are known as dermatophytes. Common genera include Microsporum and Trichophyton. They live in the outer layer of the skin called the stratum corneum which is mainly composed of rough dead skin cells known as keratinized cells. 

How is Ringworm Transmitted?

Ringworm is  transmitted through direct contact with an infected individual or an object that has previously been exposed to pathogen, such as clothing and bedding (fomites). Ringworm is a zoonotic disease meaning it can be transmitted between animals and humans. 

Clinical Symptoms Include...

  • Slightly raised red lesions
  • Circular patches of hair loss (alopecia)
  • Scaly, crusty or ulcerated skin
  • Brittle hair
  • May or may not be itchy (pruritus)

How is Ringworm Diagnosed?

Ringworm is diagnosed with a Wood’s lamp combined with hair microscopy and fungal culture.  A Wood’s lamp is a portable black light that causes certain types of fungi to glow (fluoresce) in a dark room. A positive result is indicative of ringworm, however a negative result does not rule it out as only some species of Microsporum fluoresce.  Hair microscopy involves examining a hair sample under a microscope to look for the presence of dermatophytes. This technique is used to confirm the results of Wood’s lamp test.

A fungal culture is the most reliable diagnostic test for ringworm. It is performed by taking a hair sample containing dead skin cells from the outer edges of the lesion with tweezers or a toothbrush. The sample is placed in a bottle of dermatophyte test medium and stored in a dark place at room temperature for 10-14 days. If dermatophytes are present in the sample, the agar (a component of the test medium) will change from  orange to red.

What are the Treatment Options for Ringworm?

Treatment of ringworm  may consist of a topical ointment or solution that is applied to the infected area and/or oral antifungal medication. 

  • Lime sulfur dip is a topical solution that is commonly used to treat ringworm.
  • Antifungal shampoos containing an antifungal medication, such as miconazole are also available.
  • Prescribed antifungal medications including ketoconazole, terbinafine, and fluconazole

When Handling a Pet with Ringworm, Remember to:

  • wear disposable gloves and dispose of them immediately after use
  • cover exposed skin 
  • thoroughly decontaminate all surfaces with a 1:10 bleach solution 
  • minimize contact with infected animals until the infection has resolved

In compliance with the FTC guidelines, ATC Pet Talk is a participant in the Amazon Services LLC Associates Program. Pages on this site may include affiliate links to Amazon and other affiliate sites on which the owner of this website will make a referral commission. Products recommended on ATC Pet Talk are ones that the owner has or would use herself. ATC Pet Talk does not receive free products for review. ATC Pet Talk would like to thank you for your financial support.


Share on facebook
Share on twitter
Share on pinterest
Share on email

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Read more for Privacy Policy, Terms & Conditions. Accept Read More