Read condition-specific symptoms and clinical context for Herpes simplex viruses. Two related viruses that cause cold sores or genital herpes and stay for life.
WHO describes herpes simplex virus as a common infection spread mainly by skin-to-skin contact, treatable but not curable. HSV-1 mostly spreads by oral contact and causes infections in or around the mouth, and can also cause genital herpes; HSV-2 spreads by sexual contact and causes genital herpes. Most people have no symptoms or only mild ones.
CDC states that HSV-1 often causes oral herpes, that most people with oral herpes have no symptoms, and that most acquire it in childhood or young adulthood from non-sexual contact with saliva.
Possible symptoms: Cold sores or fever blisters on or around the mouth; Painful blisters or ulcers that can return over time.
WHO notes that recurrent symptoms of oral and genital herpes may be distressing. Most people never know they are infected, and only a clinician can identify the cause of a sore.
CDC states that genital herpes often has no symptoms, and that mild symptoms may go unnoticed or be mistaken for another skin condition such as a pimple or ingrown hair, so most people do not know they have the infection.
Possible symptoms: One or more blisters on or around the genitals, rectum or mouth; Painful sores that may take a week or more to heal; Fever during a first outbreak; Body aches during a first outbreak; Swollen glands during a first outbreak.
CDC advises seeing a healthcare provider for an unusual sore, smelly genital discharge, burning when urinating or bleeding between periods. Repeat outbreaks are usually shorter and less severe than the first, and the number of outbreaks may decrease over time.
Source check: 2026-09-19. Educational content; independent scientific review remains pending.