Fungal agents which have a propensity to infect skin and hair are called dermatophytes. Dermatophytes can be classified as either geophilic, zoophilic or anthropophilic, according to their primary habitats, which are soil, lower animals, or man, respectively. Most common infections are caused by Microsporum or Tricophyton spp, i.e. Microsporum canis, Microsporum gypsum and Trycophyton rubrum.
Several of the geophilic and zoophilic organisms are occupational hazards for agricultural workers. Agricultural workers may be exposed to dermatophytes by direct or indirect contact with infected animals or soil. Breaks in the skin enhance the ability of the organism to establish an infection and agricultural workers are very prone to lacerations or abrasions on their hands and arms. As hands and arms are commonly unprotected with clothing and are frequently in contact with potentially infected animals or fomites, these parts are the most common sites for infection.