Fungi is a group of organisms that include microscopic ones like, yeast and mold; and bigger ones like, mushrooms. Various types of fungus are present on and inside the human body, and most of them are beneficial. However, an overgrowth of beneficial fungi or the presence of harmful fungi can lead to infections, that can affect different body parts. The symptoms of fungal infection differ with the affected body part and the causal agent. Three Basic Types of Fungal Infections Fungal infections are divided into three types - superficial, systemic and opportunistic. Superficial infections are very common, and affect the skin and mucous membranes of the body. There are various types of superficial fungal infections. This type is not considered life-threatening, but may affect the quality of life and sometimes turn systemic. Some of the superficial infections may also spread to other people. Unlike the first category, systemic fungal infections affect the organs inside the body, as the fungus enters the blood stream. This type is more severe, as compared to superficial types, and can also be life-threatening. The third type, called opportunistic fungal infections affect those with a weak immune system, and can be either superficial or systemic. These three categories have many sub-categories, which are classified on the basis of the affected body part and the type of fungus. Infections of Skin and Nails There are different types of fungal skin infections, like ringworm, tinea versicolor, jock itch, and athlete's foot. Fungus prefers the warm and moist areas of the skin. Both mold and yeast affect the skin. Among the various types of fungal skin infections, athlete's foot or Tinea pedis is the most common one, and affects both men and women alike. It affects the web spaces between the toes, and the skin of that part becomes soggy and itchy. It can turn pale and scaly too. Jock itch or ringworm of the groin (Tinea cruris) causes red rash in the groin area. The affected area can be itchy, and the condition is commonly found in men who sweat a lot. Ringworm of the body or Tinea corporis is mostly seen in exposed areas, like limbs and abdomen. These red rashes have scaly edges that surround clear skin. Ringworm of the scalp is otherwise known as Tinea capitis, which is characterized by patches on the scalp, along with hair loss and swelling of that area. Fungus on the skin includes nail fungus infections (onychomycosis), and ringworm of the nails (Tinea unguium) is the most common one. This condition makes the nails abnormally thick and crumbly. Yeast Infections Yeast is a type of fungus that is the causal agent of various fungal infections. Such infection of the mouth (oral thrush) is characterized by a white coating of the tongue, inner cheeks, gums, and tonsils. This coating, when scraped, may bleed and may also cause pain. Oral thrush is caused by Candida albicans fungus. This fungus may affect the esophagus and the intestines too. Candida albicans may also affect the mucous membrane of the vagina; and cause symptoms, like itchiness and thick white discharge, along with painful urination. In case of men, it causes painful red rash on the tip of the penis. Infections of Internal Organs There are many other types of fungal infections that affect the brain and lungs. Fungal meningitis causes inflammation of the membranes that cover the brain and spinal cord, and is caused by a fungus called Cryptococcus. Even though, the symptoms may vary from one person to another, the most common ones are headaches, drowsiness and confusion. Another fungus, called Aspergillus, which is a mold, causes bloodstream infections in people affected with cancer and HIV/AIDS. Other types include coccidioidomycosis that also known as valley fever, blastomycosis, fungal arthritis, fungal sinus infection, histoplasmosis that affects vision; and mucormycosis characterized by pain, fever, infection of eye socket and nasal discharge. Early diagnosis and treatment are very much important to prevent spread of infection and for relief from the symptoms. Excess use of antibiotics, a weak immune system, diabetes, poor personal hygiene, etc., are cited as factors that make people prone to fungal infections. Disclaimer: This article is for informational purposes only and should not be used as a replacement for expert medical advice. Visiting your physician is the safest way to diagnose and treat any health condition.