Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
No one knows where a specific person catches the fungus, as it is everywhere. However, since the fungus does thrive in warm moist areas (like sweaty feet), there are certain areas one should avoid or use with caution. Shower floors, locker rooms, and swimming pools are suspected of being sources of the fungus, although there are no studies proving this fact. Nail polish and acrylic nails also make the nail less "breathable" and make the nail more susceptible to fungal infection. Fungi are everywhere -- in the air, the dust, and the soil. Hygienic measures such as spraying socks and footgear sound sensible, and perhaps these measures can even help a little bit. However, avoiding tight, nonbreathing shoes or steering clear of athletic facility floors may very well be the best prevention available. Daily washing of the feet and drying between the toes can help to prevent nail fungus. The fungi carried on the coats of pets, like cats and dogs, don't often cause nail fungus. Wearing white socks does not help.
Toenail fungus is an infection that gets in through cracks in your nail or cuts in your skin. It can make your toenail change color or get thicker. It can also hurt. Because toes are often warm and damp, fungus grows well there. Different kinds of fungi and sometimes yeast affect different parts of the nail. Left untreated, an infection could spread to other toenails, skin, or even your fingernails.