| umls-concept:C0019345 | skos:definition | MSH: Herpes simplex, caused by type 1 virus, primarily spread by oral secretions and usually occurring as a concomitant of fever. It may also develop in the absence of fever or prior illness. It commonly involves the facial region, especially the lips and the nares. (Dorland, 27th ed.),MEDLINEPLUS: <p>Cold sores are caused by a contagious virus called <a href='http://www.nlm.nih.gov/medlineplus/herpessimplex.html'>herpes simplex</a>. There are two types of herpes simplex virus. Type 1 usually causes oral herpes, or cold sores. Type 1 herpes virus infects more than half of the U.S. population by the time they reach their 20s. Type 2 usually affects the <a href='http://www.nlm.nih.gov/medlineplus/genitalherpes.html'>genital area</a> </p><p>Some people have no symptoms from the infection. But others develop painful and unsightly cold sores that last for a week or more. Cold sores usually occur outside the mouth -- on the lips, chin, and cheeks, or in the nostrils. When they do occur inside the mouth, it is usual | lld:umls |
