HERPES VIRUSES
There are eight known human herpes
viruses. Herpes simplex and herpes
varicella-zoster cause skin conditions. The
other viruses in the herpes family may cause malaise but do not affect the skin.
By adulthood, herpes simplex infection affects 95% of the population.
Type 1, being more prevalent than type 2.
Infection rates are detected by antibody tests, since the majority of
people infected are unaware of it, having experienced no symptoms.
Recurrences only affect a minority of those infected and occur due to a
lowered immune response which may be triggered by illness or stress, for
example. Infection with chickenpox
is virtually universal. Shingles is
more likely to affect older people (50% at 85 years), often following trauma to
the area. Post-herpetic neuralgia (PHN)
occurs in a rising proportion of older patients: from 50% of 60 year olds with
shingles to 70% of those aged 75.
Causes and Symptoms
Herpes simplex is contracted by direct
skin-to-skin contact with the affected part.
Chickenpox is both contagious and infectious.
Herpes simplex virus types 1 and 2
produce the symptoms known as cold sores (on the face), herpetic whitlows (on
the fingers) and ‘herpes’ elsewhere on the body.
Herpes varicella-zoster is called chickenpox when it first occurs and
shingles if it recurs.
The incubation period for herpes simplex
is usually 2-14 days, however asymptomatic carriers may develop symptoms years
after they have contracted it. Chickenpox
has an incubation period of 14-21 days. The
primary illnesses last about 2-3 weeks and are self-limiting.
Flu-like symptoms occur, followed by blisters or spots which open into
sores or ulcers, before scabbing over and healing.
After the primary infection is cured by the immune response, simplex and
varicella-zoster remain latent in nerve ganglions and may reactivate at a later
date.
Herpes simplex recurrences only affect
the dermatome (area of skin served by the branches of a single spinal sensory
nerve) where infection took place, causing one or more spots usually without any
systemic illness. However
neurological symptoms, described variously as scalded skin, deep aches or
shooting nerve pains, may be experienced in the dermatome either before, or
between, outbreaks. Symptoms are
not transmitted to other nerve regions. With
time recurrences diminish.
Chickenpox affects the entire body, so
bouts of shingles can appear anywhere but are commonly experienced on the thorax
or head. The vesicles follow the
line of the nerve. Neurological
damage (post-herpetic neuralgia) can leave excruciating pain which may last for
many months.
A diagnosis of herpes simplex can be
very distressing. Since the early
1980s, inaccurate and deliberately misleading information has been printed in
newspapers and magazines. As a
result, a diagnosis can often cause greater psychological misery than the
physical suffering. Sexually
transmitted conditions carry a stigma in this country, exacerbated by an
immature national attitude to sex, characterized by prurience and prudery.
The ‘herpes hype’ and stigma associated with the condition means that
most people remain secretive about the condition, sometimes even with the person
from whom it was contracted.
Treatments
If the primary infection of simplex and
chickenpox is severe, and when a shingles outbreak affects an older patient, one
of the newer antiviral medications may be prescribed.
In less severe cases all that is necessary is to alleviate symptoms,
using antipyretics, analgesics and topical anesthetics, as appropriate.
Simplex or zoster affecting the
ophthalmic division of the trigeminal nerve not only causes pain, but may also
lead to blindness. Oral antiviral
therapy is recommended for this condition.
If simplex recurs with a frequency that
the patient finds distressing, antiviral treatment may be given prophylactically
for a period of six months (the minimum time for effective treatment), though
self-help is often much more effective.
Prescribed treatments to block
post-herpetic neuralgia include tricylic anti-depressants or topical
applications. Self-help such as
firm bandaging or the use of a TENS (transcutaneous electrical nerve
stimulation) unit may alleviate the pain.
any questions email us at doctor@skinpatient.com
