The skin, the largest organ in the human body, is the first line of defense against the environment. In addition to being a protective shield, it also helps to regulate body heat, sense stimulation and store water, fat and vitamin D according to the University of Maryland Medical Center. The skin is made up of living cells, blood vessels, lymph vessels, hair follicles and sweat glands, making it vulnerable to attack by outside organisms. A temporary skin rash is the most common ailment involving the skin.
Virus
Viruses, microscopic organisms that depend upon the host cell to live, can cause temporary skin rashes. Many childhood illnesses, including chicken pox, measles, mumps, rubella and hand-foot-and-mouth disease are caused by viruses that produce pronounced skin reactions. Some viruses, including the chicken pox virus, can lay dormant in the cells of the body for many years only to resurface later. The skin rashes caused by these viruses appear like blisters that may seep fluids and then crust over before healing.
Bacteria
There are many types of bacteria that normally reside on the skin. These include some strains of Staphylococcus, Corynebacterium, Brevibacterium and Acinetobacter. Although these bacteria do not usually cause harm, they can gain entry into the skin through wounds or cracked skin caused by eczema, which can lead to a temporary rash.
Impetigo is a common skin infection caused by Staphylococcus bacteria. The rash will present as round patches of oozing blisters that may be either clear or golden yellow in color. This type of rash is very contagious according to DermNet New Zealand.
MRSA, methicillin-resistant Staphylococcus aureus, is a skin infection caused by the Staphylococcus aureus bacteria. The rash caused by MRSA begins as small red bumps that can progress to large painful lesions. Because this bacterium is resistant to wide spectrum antibiotics, it can be fatal as reported by the doctors at the Mayo Clinic.
Fungus
Fungi are found everywhere: in dirt, on floors and on people. The skin is usually resistant to fungus and able to fight it off. However, for some people, their skin is not able to recognize the fungus as a foreign object therefore allowing it to grow. Because fungi thrive in dark and moist environments, they most commonly occur on the skin of the feet, hands, nails and groin. The most common skin rashes caused by a fungus are ringworm and athlete's foot.
Allergic Reaction
Contact dermatitis is a type of skin rash that occurs in response to contact with an allergen. The most common contact allergens are nickel, rubber, cosmetics, nail polish and weeds such as poison ivy. The rash produced is red, itchy and dry and will usually resolve on its own in two to three weeks after the offending item is removed as reported by the Mayo Clinic.
