The Fungi overgrowth can cause symptoms. As a common example, Candida is a yeast that can be found on the skin or mucous membranes or maybe in the intestinal tract. The infection, candidiasis can develops in the mouth, throat or in the vagina. For people with certain risk factors, overgrowth of these fungi can cause invasive candidiasis, a serious infection that can affect the blood, heart, brain, eyes, bones, as wll as other parts of the body.