There are a
wide variety of methods of diagnosis genital herpes. The journey to diagnosing
this disease begins with a visit to a healthcare
diagnosis of herpes begins with a history and
physical examination by a healthcare professional (nurse
practitioner, physician's assistant or a physician). During the history, you will
provide as much accurate information about your symptoms as you
can. Important details
include sexual history, any symptoms that your partner may have, any
symptoms you have and when these symptoms started. During the physical
examination, your provider will inspect any lesions or areas of
concern. Your provider
will then combine the information you have given with what he or she
finds on physical exam to determine what the most likely
The accuracy of
the clinical diagnosis will depend on the clinician, the history you
provide and what (if anything) is seen on physical exam. A clinical diagnosis can be
reliable in many cases.
However, the ulcers caused by genital herpes may look like
ulcers from other diseases such as syphilis, chancroid, Behcet's
disease and a few other conditions. Therefore if there is any
doubt regarding the diagnosis or if your symptoms are not "typical"
for genital herpes, laboratory testing can be used to make a more
Laboratory testing is also suggested to confirm a clinical
A viral culture
involves taking a sample from an active lesion. An active lesion is a vesicle (blister)
or an ulcer. The
clinician will need to puncture the roof of the blister remove fluid
from it. If an ulcer is
present, a swab will be used to take a sample from the base of the
ulcer. The viruses will
usually grow in the culture by 5 days. This test is most accurate
when the lesion is in the early blister stage rather than in the
later stages when the lesion has crust on it. The ability of this test to
detect the virus is also higher with the first herpes outbreak
rather than during a recurrence. Once the virus has grown,
the type (HSV-1 or HSV-2) can then be determined by further testing.
chain reaction (PCR) involves taking a sample from a lesion or a
genital area (vagina, cervix, rectum or penis) and analyzing it for
the DNA of the herpes virus. This test is more
sensitive than viral culture and can be done rapidly such that the
results are available in the same day. This utility of this test is
reduced by its limited availability and lack of standardization for
a variety of samples.
involves directly examining individual cells.
smear (Pap smear) is a test usually used to screen for cervical
cancer. This test can
also detect cells infected with HSV even if the woman does not have
symptoms. This is
not a usual method of diagnosis.
A Tzanck smear
requires a sample from an active genital lesion. It is limited in utility
because it is not very sensitive and does not distinguish between
HSV -1 or HSV-2.
Fluorescent Antibody (DFA) relies on samples from lesions. This test is sensitive and
able to distinguish between HSV-1 and HSV-2 but can at time deliver
falsely positive results.
analyze blood samples. When a foreign substance (an antigen) enters
the bloodstream, the body's immune system forms a protein called an
antibody to help fight the antigen. When someone is infected
with the herpes virus (an antigen) the body will form an antibody
against it within 10-20 days.
There are two main antibodies formed against herpes,
Immunoglobulin M (IgM) and Immunoglobulin G (IgG). IgM antibodies are the first
to be formed and can usually be detected in the blood 9-10 days
after an exposure to the virus. They will usually last for
7-14 days but some people may have them for up to six weeks. IgG antibodies develop later
than IgM antibodies. It
may take several weeks to months for them to develop.
Herpeselect tests can test
for the herpes virus antibodies and distinguish between HSV-1 and
HSV-2. The tests are
based on the antigen glycoprotein G1 (gG1) that is specific to HSV-1
and the antigen glycoprotein G2 (gG2) that is specific to
has two types of tests: the immunoblot and the ELISA. Though the laboratory
methods of the two tests differ, the principle is the same:
detecting IgG antibodies in your blood that interact with either the
HSV-1 (gG1) or theHSV-2 (gG2) antigens. These tests are very
sensitive and can detect the herpes simplex antibodies in the blood
even if you are not having symptoms.
If the test is
positive, that means the IgG antibodies to herpes simplex were found
in your blood. The test
will determine if you have antibodies to the HSV-1, HSV-2, or
both. Having the HSV-1
or HSV-2 IgG antibodies in your blood means that you have been
exposed to the herpes virus and have been infected. A positive test for HSV-2
antibodies in the blood likely represents genital infection. Because HSV-1
infections can occur in the genital area or the mouth, a positive
test for HSV-1 antibodies cannot tell you whether the infection is
in the genitals or the mouth.
This test cannot tell you when you were infected. The amount of antibody in
the blood does not coordinate with the severity of the infection or
how well medications are working to treat the infection. If the test is negative, it
means that you are either not infected OR the infection happened so
recently that your body has not had time to react.
Herpeselect tests for the
IgG antibody, it does not test for IgM. There are tests available to
look for IgM. If the
test for herpes virus IgM is positive, the usual assumption is that
the infection is recent.
However, IgM levels can also be elevated in individuals who
are having a recurrence of herpes. If this is the case, the
level of antibody will usually be lower than in the initial
infection. The tests
available for IgM do not distinguish between HSV-1 and
Disclaimer: This article is not meant to
provide specific medical advice and is not a substitute for an
examination by a physician or other qualified healthcare
clinical manifestations, and diagnosis of genital herpes simplex
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