Environmental and Genetic Factors on the Development of Onychomycosis.

Since the early 20th century, onychomycosis originated with the onset of war, the use of occlusive footwear, and the mass migration of people by transportation in the United States. Even though onychomycosis has a high prevalence in the US, other parts of the world including Canada, West Africa, Southeast Asia, Northern Australia, and Europe have been well documented with cases of fungal toenail infection in their environments. Trichophyton rubrum (T. rubrum) is the major dermatophyte responsible for toenail fungal infection and is typically diagnosed in conjunction with tinea pedis, especially in individuals older than 60 years. Gender roles, age, cultural habits, shoe gear, sports activities, and genetic predisposition all contribute to the different presentation of onychomycosis in these areas where organisms like dermatophytes, candida, and molds were isolated in a variety of cases. Despite the differences in isolated pathogens, treatment outcomes remained consistent. This literature review discusses the influence of tinea pedis, genetics, shoe gear, sports, and age on the development of onychomycosis.