Vinegar! Kills
fungus and bacteria, and is all NATURAL! Use it straight if you want, but you can mix it in a 50/50 mix with water. Vinegar works for cleaning windows, sanitizing counters, LOTS of stuff! It will also kill bottle bacillus, the bacteria that causes itchy scalp. Keep it in a large spray bottle. Spray it on glass, scalp, scrotum, anywhere!
Keep using it on your scrotum, penis, inside of thighs until it's gone, morning and night after showering.