Genital Herpes (Herpes Simplex Virus)
Genital herpes is a
contagious viral infection that affects an estimated 23 percent
of adult Americans. Each year, as many as 500,000 new cases are
believed to occur. The infection is caused by the herpes simplex
virus (HSV).
There are two types of HSV, and both can cause the
symptoms of genital herpes. HSV type 1 most commonly causes sores
on the lips (known as fever blisters or cold sores), but it can
cause genital infections as well. HSV type 2 most often causes
genital sores, but it also can infect the mouth.
HSV 1 and 2 can both produce sores
in and around the vaginal area, on the penis, around the anal
opening, and on the buttocks or thighs. Occasionally, sores also
appear on other parts of the body where broken skin has come into
contact with HSV. The virus remains in certain nerve cells of the
body for life, causing periodic symptoms in some people.
Genital herpes infection usually
is acquired by sexual contact with someone who has an outbreak of
herpes sores in the genital area. People with oral herpes can
transmit the infection to the genital area of a partner during
oral-genital sex. Herpes infections also can be transmitted by a
person who is infected with HSV but has no noticeable symptoms.
The virus is spread only rarely, if at all, by contact with
objects such as a toilet seat or hot tub.
Symptoms
Most people who are infected with
HSV never develop any symptoms. When symptoms do occur, they vary
widely from person to person. Symptoms of a first episode of
genital herpes usually appear within two to 10 days of exposure
to the virus and last an average of two to three weeks. Early
symptoms can include:
- Itching or burning sensation.
- Pain in the legs, buttocks,
or genital area.
- Vaginal discharge.
- Feeling of pressure in the
abdominal region.
Within a few days, sores (also
called lesions) appear at the site of infection. Lesions also can
occur on the cervix in women or in the urinary passage in men.
These small red bumps may develop into blisters or painful open
sores. Over a period of days, the sores become crusted and then
heal without scarring. Other symptoms that may accompany a
primary episode of genital herpes can include:
- Fever.
- Headache.
- Muscle aches.
- Painful or difficult
urination.
- Vaginal discharge.
- Swollen glands in the groin
area.
Recurrences
In genital herpes, after invading
the skin or mucous membranes, the virus travels to the sensory
nerves at the end of the spinal cord. Even after the skin lesions
have disappeared, the virus remains inside the nerve cells in an
inactive, latent state. In most people, the virus will reactivate
from time to time. It travels along the nerves to the skin, where
it multiplies on the surface at or near the site of the original
herpes sores, causing new sores to erupt. It also can reactivate
without causing any visible sores. At these times, small amounts
of the virus may be shed at or near sites of the original
infection, in genital secretions, or from barely noticeable
lesions. This shedding is infrequent, however, and usually lasts
only a day, but it is sufficient to infect a sex partner.
The symptoms of recurrent episodes
usually are milder than those of the first episode and typically
last about a week. A recurrent outbreak may be signaled by a
tingling sensation or itching in the genital area, or pain in the
buttocks or down the leg. These are called prodromal symptoms,
and, for some people, they can be the most painful and annoying
part of a recurrent episode. Sometimes only the prodrome is
present and no visible sores develop. At other times, blisters
appear that may be very small and barely noticeable, or they may
break into open sores that crust over and then disappear.
The frequency and severity of the
recurrent episodes vary greatly. While some people recognize only
one or two recurrences in a lifetime, others may experience
several outbreaks a year. The number and pattern of recurrences
often change over time for an individual. Scientists do not know
what causes the virus to reactivate. Although some people with
herpes report that their recurrences are brought on by other
illness, stress, or menstruation, recurrences often are not
predictable. In some cases, exposure to sunlight is associated
with recurrences.
Diagnosis
The sores of genital herpes in its
active stage are usually visible to the naked eye. Several
laboratory tests may be needed, however, to distinguish herpes
sores from other infections. The most accurate method of
diagnosis is by viral culture, in which a new sore is swabbed or
scraped and the sample is added to a laboratory culture
containing healthy cells. When examined under a microscope after
one to two days, the cells show changes that indicate growth of
the herpes virus.
A newer, more rapid, but somewhat
less accurate way of diagnosing herpes involves detection of
viral protein components in lesion swabs. These tests should be
done when the sores first appear to ensure the most reliable
results. Other laboratory tests also are available to physicians.
It is important to note that because clinicians commonly fail to
detect HSV in an active sore, a negative virus culture does not
always mean that a person is not infected with the virus.
A blood test cannot determine
whether a person has an active genital herpes infection. A blood
test, however, can detect antibodies to the virus, which indicate
that the person has been infected with HSV at some time and has
produced antibodies to it. (Antibodies are proteins made by a
person's immune system to fight infections.) Unlike
antibodies to some other viruses, however, antibodies to HSV do
not totally protect an individual against another infection with
a different strain or a different type of herpes virus, nor do
they prevent a reactivation of the latent virus. Antibody tests
are the best way to determine if a person is an HSV carrier. The
standard blood tests only reliably indicate whether a patient has
had a herpes infection, not the type of HSV.
New blood tests have been
developed that can distinguish whether a person has had prior
type 1 or type 2 infection, or both. However, these tests are
available mainly in research hospitals and are not used routinely
in the doctor's office.
Treatment
During an active herpes episode,
whether primary or recurrent, it is important to follow a few
simple steps to speed healing and to avoid spreading the
infection to other sites of the body or to other people:
- Keep the infected area clean
and dry to prevent secondary infections from developing.
- Try to avoid touching the
sores; wash hands after contact with the sores.
- Avoid sexual contact from the
time symptoms are first recognized until the sores are
completely healed, i.e., the scab has fallen off and new
skin has formed over the site of the lesion.
Researchers have shown that the
oral form of acyclovir (Zovirax®) is a superior and safe
treatment that helps patients with first or recurrent episodes of
genital herpes. The oral form of the drug is taken five times a
day and markedly shortens the course of the first episode and
limits the severity of recurrences, particularly if taken within
24 hours of onset of symptoms. People who have very frequent
recurrent episodes of the disease can take oral acyclovir twice
daily for up to one year at a time to suppress the virus'
activity and prevent most recurrences. After a year, it is
reasonable to stop the medication and only to restart it if
frequent recurrences resume. Acyclovir is not a cure for
herpes—the virus remains in the body; but while taken
regularly, the medicine interferes with the virus' ability
to reproduce itself.
The U. S. Food and Drug
Administration recently approved two new drugs, famciclovir
(Famvir®) and valacyclovir (Valtrex®), to
treat recurrent episodes of genital herpes. Famciclovir also has
been approved for use in suppressing viral activity and
preventing recurrences. These two drugs can be taken less
frequently than acyclovir, i.e., three times a day for recurrent
episodes and twice daily to help stop further recurrences.
Information provided by the
National Institutes of Health
Article Created: 1999-07-02 Article Updated: 1999-12-23
Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.
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