Fungal nails have a number of causes, however many people do not know and are interested about the science behind it. A nail fungal infection is caused by a few organisms, three to be exact. These organisms target skin, hair, and nails, thriving off of the tissue on the nail (which is known as dermatophytes), yeasts, and dermatophyte molds. Of these three cases, they all result in alike symptoms, both early stages and chronic stages. With that said, the appearances will be similar and may not reveal which particular case of fungus you may have. Globally, the most common cause for a nail fungal infection is Dermatophytes (such as Trichophyton, Epidermophyton, and Microsporum species). About 8% of the infections are caused by yeast, and the remaining 1% are caused by non-dermatophyte molds.
Dermatophytes, as mentioned above, target the hair skin and nails, as they use keratin found in these body parts. These dermatophytes are typically spread through direct contact from organisms found in humans, animals, and soil.
Yeast is typically responsible for the fungus growth on skin. Being sick, the use of antibiotics, birth control, and issues with the immune system, all may lead to an increase in the growth of yeast in the body, which is how yeast infections form.
Lastly, molds, which are the least common, is a type of fungus that develops in soil most often and can grow onto the skin and nails. These are not typically passed through human contact but still can be.
Although there are several causes of a nail infection, it is still a nail fungus nonetheless and all categories still require the same treatment options.