A fungal infection can lead to itching around a man’s or woman’s genitals. A woman can also have a fungal infection in the vagina. A fungal infection can be extremely itchy. The infection is usually caused by a type of yeast called candida. This fungus multiplies if the natural balance of bacteria in the vagina is disturbed. This can take place if the woman is taking antibiotics such as penicillin. A fungal infection is not a sexually transmitted disease, and a doctor will be able to treat it effectively. In order to avoid fungal infections it is best not to wear close-fitting trousers and underwear made of artificial fibres which do not let air circulate.