Regular skin - skin on the hand, for example - is protected against
all but the most massive invasion because of a natural barrier on the skin called
keratin. Keratin is waxy and strong. Just as it repels water, it
repels herpes virus particles. Unless the keratin is torn, in a cut for instance,
the virus cannot get to an epithelial cell. In mucous membranes, however, like
those lining the mouth, eye, and genital area, the barrier is very thin, and
the epithelial cells are very near the skin surface. This is where access is
easiest. To transfer the infection, one person needs to have an active lesion
with herpes; there must be friction for heat and for removal of infected cells
from the surface of the infected person; there must be moisture for easy travel
of the virus and to prevent drying; and there must be contact with exposed epithelial
cells of another susceptible person. A new infection is the result.
Thus, genital herpes tends to be sexually transmitted. Other types
of transmission are possible but not usual. Most friction-, moisture-, and heat-producing
contact between two people involving the skin of the genitals is sexual. Herpes
simplex can be transmitted, for example, from a penile sore to a vagina. However,
transmission of genital herpes does not actually require genital penetration.
Sexual contact may include a nongenital sore contacting a genital target. In
other words, herpes may be transmitted from the source partner's mouth to the
other partner's vagina, or from mouth to penis, penis to mouth, finger to penis,
penis to anus, or any other combination. The only requirements are infected
cells and exposure to new cells belonging to a new, susceptible person, along
with heat and moisture.
These requirements are also met in a variety of contact sports. Herpes simplex
virus does not care if sex is happening. Sure, herpes likes sex, but sex is
only one type of contact sport that generates heat, moisture, and friction-based
skin-to-skin contact. Herpes can be spread during wrestling, rugby, or any other
contact sport that exposes a new susceptible host to infectious virus and thus
provides the new environmental opportunities the virus constantly seeks to restart
its reproductive cycle in a new host.