How is Toenail Fungus Spread? [Causes & Best Treatment!] How is Toenail Fungus Spread? The #1 cause is communal areas where family members or the public walk barefoot. STOP CATCHING IT! How is Toenail Fungus Spread Overview: The number one way toenail fungus is spread is in communal areas like showers, bathrooms and pool decks. … Read more