Oral candidiasis or thrush is a fungal infection of the Candida species and affects the mucus membrane of the mouth. It may affect healthy people but more commonly affect those who are immunosuppressed. It causes a white plaque in the oral cavity or on the tongue. The plaque can be scraped off, unlike the plaque of leukoplakia. It may cause a cottony feeling in the mouth and loss of taste. Treatment is with oral an antifungal.