The herpes simplex virus (HSV) is a double-stranded DNA virus with an enveloped, icosahedral capsid.
Although HSV-1 is mainly localized around the oral region and HSV-2 around the genital region, it is quite possible to transmit the virus to either region, from either region, resulting in painful sores; the virus in incurable.
Upon entering the body through oral or genital transmission, HSV penetrates the nerve cells (primary sensory neurons) in the lower layers of human skin tissue and replicates itself in the cell nuclei, thus destroying host cells.
After destruction of the nerve cells, blisters and inflammation present itself in the region where the virus was contracted, oral or genital.
Towards the end of the visible infection (3-14 days), viral particles are carried from the skin through the branches of nerve cells to ganglia, where the virus persists in a latent form until it recurs in an active, visible form (The recurrence rate of HSV-1(recurrent herpes) after the initial flare-up (primary herpes) is 20% to 40%, while the recurrence rate of HSV-2 is much higher at 80%.
Men experience 20% more recurrences of genital herpes than women, even though symptoms in males are milder and shorter.
Reactivation causes recurrent disease (oral or genital herpes), but most often it leads to shedding of infectious virus from the skin or mucous membranes, thus leading to further transmission of the virus.
Transmission is usually accomplished when unrecognized or asymptomatic viral shedding is occurring.
Active eruptions may occur as often as every few weeks or as seldom as once a year, and they usually appear at the same site.
Many factors can initiate a recurrence, such as sunlight, menstruation, wind, fever, suppression of immune system, emotional stress, and intense dental work.