A virus that has the ability to infect the host, initially causing little or no evidence of illness but persisting for the lifetime of the infected individual; later on, a specific triggering mechanism may cause the virus to produce a clinically apparent disease. This occurs with herpes simplex virus that remains latent in sensory ganglia and is reactivated by trauma to the skin supplied by the distal sensory nerves associated with these ganglia. After reactivation, the virus may cause localized or generalized lesions in the affected area and the central nervous system.
A dormant form of a virus that remains inactive within a cell is referred to as a latent virus. In the case of the herpes virus, it maintains a latent state within cells of the nervous system.