Oral herpes is a diseased caused by a virus, generally herpes simplex 1 (HSV-1). It can cause painful sores in and around the mouth or can exhibit no symptoms at all. Because it is so contagious, it is estimated that at least 50% of people have had contact with a subtype of the herpes virus before they reach adulthood.
The herpes oral strain is only present in humans, and is transmitted though contact with infected skin, saliva, or mucous membranes. Symptoms of vary from person to person, depending upon the locations and severity of the infection. Early and less severe symptoms of oral herpes mimic those of the flu and can include fever and headache, and depression or irritability, and inflammation of the lymph nodes, particularly those located near the site of the pending outbreak.
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