The herpes IgG test is a blood test used to diagnose herpes simplex virus (HSV).
A positive test result indicates that you were infected with HSV-1 or HSV-2 sometime in the past.
The herpes IgG is not used as a general screening test.
Verywell / Cindy Chung
It is recommended for those who havesymptoms of genital herpesto confirm that they have it.
This includesprenatal STI screeningwhen you are pregnant.
However, this test is not recommended for general STI testing or as a routine test during pregnancy.
Current IgG tests are up to 97% accurate in detecting HSV-1 and 98% accurate in detecting HSV-2.
There is also aherpes IgM testthat detects a shorter-lasting antibody known as immunoglobulin M (IgM).
Thereafter, IgM rapidly declines after a few weeks or months to undetectable levels.
This differs from IgG antibodies that can be detected for a lifetime.
The herpes IgM test has limitations in that it cannot differentiate between HSV-1 and HSV-2.
How It Works
The herpes IgG test detects IgG antibodies in the blood specific to HSV.
It does so when theimmune systemhas produced enough IgG antibodies to be detectable by current lab tests.
Some people have been known to only test positive for HSV a full six months after infection.
A negative herpes IgG test means that you have never been infected with HSV.
They might also recommend repeating the IgG test after a few weeks.
This means that between one in eight and one in 10 tests will incorrectly diagnose herpes.
Before the Test
The herpes IgG test requires no preparation or food or drink restrictions.
It is typically performed at a lab, a public clinic, or a healthcare provider’s office.
Public clinics tend to be cheaper.
Health insurance may fully or partially cover the cost of testing; check your policy details.
While many facilities offer drop-in testing, some require an appointment.
Based on your response, the counselor may recommend additional STI screenings.
You may also experience soreness, swelling, or bruising at the injection site.
Lightheadedness can also occur.
Your test results should be ready within two to five working days.
The timing may vary depending on the clinic or lab.
Can You Get Rid of HSV-1 or HSV-1?
Once you are infected with HSV, it stays with you for a lifetime.
There is no cure for herpes and the virus cannot be cleared by the immune system.
Summary
A herpes IgG test is a blood test used to diagnose genital herpes.
It detects antibodies produced by the immune system in response to the virus.
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