10 - How is herpes simplex caught and passed on?
The virus is passed directly from skin to skin with friction. It enters easily through mucous membranes, i.e. the moist skin which lines the mouth and genital-anal area. It can also enter through a cut or break in the ordinary skin on other parts of the body: fingers/hands, knees, etc. We call it a whitlow when it's on the fingers.
You can pass it on whenever the virus is present on the skin surface: from the first warning signs that a recurrence is starting (tingles, aches, stabbing pains) until fresh skin has grown back. The virus may also be transmitted through asymptomatic shedding. There is more about transmission in our "Transmission" leaflet – available to members – see subscription form.
Only people who do not already carry the virus can catch it. About seven in ten adults already carry herpes simplex virus type 1 and one in ten already carry type 2.
http://www.herpes.org.uk/faq.html