What is Herpes Simplex Virus (HSV) Type 2 IgG?
Also Known As:
Herpes Serology, HSV Blood Test, Herpes Simplex Virus Culture, HSV Tissue Culture, Tzanck Smear, HSV NAAT Testing, HSV PCR Test, Direct Fluorescent Antibody Test, DFA Test, Rapid Herpes Simplex Test
Herpes Simplex Virus 1 and 2, Qualitative PCR, Herpes Simplex Virus (HSV) Culture, Herpes Simplex Virus (HSV) Type 1- and Type 2-Specific Antibodies, IgG, Serum
Genital and oral herpes are infections caused by the herpes simplex virus (HSV). HSV is spread through close contact with a person who is actively shedding the virus, usually through skin to skin or sexual contact. Patients without symptoms of HSV can still actively shed the virus and infect others.
Lab tests are used to diagnose HSV and confirm the type of virus causing an infection. Diagnostic tests may require a blood sample or a sample of fluid taken from a sore. Less commonly, a lumbar puncture may be used to diagnose an infection in the brain or spinal cord.
The purpose of testing for genital and oral herpes is to identify evidence of an HSV infection. Testing for genital and oral herpes may be ordered for several reasons, including:
- Confirming a diagnosis of HSV infection in symptomatic patients
- Diagnosing patients with a history of genital sores who don’t have symptoms
- Identifying a potential HSV infection in pregnant women without symptoms
- Understanding if a sexual partner of a person with HSV is susceptible to infection
- Estimating the frequency of future symptom outbreaks
Testing can also determine the type of HSV causing an infection. There are two main types of HSV:
- Herpes simplex virus type 1 (HSV-1): HSV-1 is the cause of most cases of oral herpes and is often contracted during childhood. HSV-1 can also be spread to the genitals during oral sex.
- Herpes simplex virus type 2 (HSV-2): HSV-2 is the most common cause of genital herpes. HSV-2 can also be spread to the mouth during oral sex, causing infections of the mouth or lips. HSV-2 is typically spread through sexual contact, including vaginal, oral, or anal sex.
What does the test measure?
Testing for genital and oral herpes detects evidence of an HSV infection. There are four types of tests that confirm the presence of an HSV-1 or HSV-2 infection:
- Viral culture: A herpes viral culture is used to determine if a skin sore is infected with HSV-1 or HSV-2 by collecting a sample from a skin sore, placing it in a special laboratory environment, and watching to see if the virus or virus-related substances grow. A viral culture is most useful early in an outbreak, when a sore is open.
- Polymerase chain reaction (PCR) testing: PCR testing, also called a viral DNA test, uses a sample taken from a patient’s sore to look for the DNA of HSV-1 and HSV-2. PCR testing can distinguish between HSV-1 and HSV-2 infections, making this test useful in determining which virus is causing a person’s infection. PCR testing is the primary method of testing samples of cerebrospinal fluid.
- Tzanck smear: The Tzanck smear uses a sample of cells scraped from a patient’s sore to look for cells that are characteristic of a herpes infection. During a Tzanck smear, cells can be examined under a microscope in a clinic or doctor’s office without needing to send the sample to a laboratory.
- Antibody tests:Antibodies are produced by the immune system in response to potentially harmful substances called antigens. Because every type of antibody is unique to a specific antigen, herpes simplex antibody testing can determine if a patient is infected with HSV-1 or HSV-2. HSV antibodies can be detected in a blood sample or a sample taken from a patient’s sore. It takes time for the body to develop antibodies, so a positive result may not occur for up to three months after the initial infection.
When should I get a genital or oral herpes test?
Testing for the viruses that cause genital and oral herpes may be ordered when a patient develops signs and symptoms of a herpes infection. Although many people who contract HSV never notice symptoms, signs of an initial infection appear 2 to 20 days after infection and depend on the type of HSV causing the infection.
When signs and symptoms of an initial infection occur, they may include:
- Small sores on the skin
- Blisters on the lips, penis, vagina, buttocks, anus, or around the mouth.
- Tingling, itching, or burning on the skin
- Fever, headache, or body aches
- Swollen lymph nodes
After the initial infection, HSV remains dormant inside of the body. HSV can reactivate throughout a patient’s life, causing symptoms of genital or oral herpes to reappear. While the trigger for an HSV outbreak is often unknown, potential triggers include a fever, stress, physical trauma, and a suppressed immune system.
Generally, expert organizations do not recommend herpes testing for patients without symptoms. An exception may be made for certain patients, including:
- Patients who have a partner with genital herpes
- Patients seeking a more complete STD test panel, including people with multiple sexual partners
- Babies born to a mother who has HSV
How to get tested
Tests for genital and oral herpes are available at doctor’s offices, medical clinics, and community-based organizations that offer STD testing. Testing is often ordered by a doctor, but maybe available over-the-counter and at community-based organizations without a physician’s orders.
Can I take the test at home?
At-home tests are available to test for evidence of an HSV infection. At-home herpes testing typically detects HSV antibodies in a self-collected sample of blood and may require additional follow-up if preliminary results are positive. At-home herpes tests can be obtained online or at a local pharmacy.