The skin surface provides the body with protection from the environment and from infection, but the skin itself may become infected by bacteria, viruses, or fungi. Some of these organisms live naturally on the body and do not normally cause disease unless they breach the barrier of the skin’s surface. Infestation of the skin by parasites, such as mites, may also occur.
Infectious organisms can enter the skin in various ways. Natural openings, such as a hair follicle or sweat gland, or broken skin at the site of an insect bite or a cut may provide a gateway for bacteria. Warm and moist areas, such as the skin between the toes, are more susceptible to fungal infections. Some common viral skin infections, such as warts, can be spread from one part of the body surface to another or may be passed from one person to another by direct skin contact.
In this section, bacterial skin infections are described first, followed by fungal and viral infections. The final article covers infestation by the scabies mite.
Diseases such as measles and rubella, in which a skin rash occurs due to an infection that also affects many other areas of the body, are covered elsewhere (see Infections and infestations). The two common skin infestations head lice and pubic lice are also described in other sections of the guide.
For further information on the structure and function of the skin.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.
The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.