Herpes Simplex Virus Type 1 Antibody, Qualitative (IgG) – Viral Serology

This test checks your blood for antibodies that your immune system makes in response to the herpes simplex virus, including HSV-1, which usually causes cold sores around the mouth, and HSV-2, which is most often linked to genital herpes. By measuring these antibodies, the test can show whether you have been exposed to the virus at some point, even if you have never noticed any symptoms.

The test detects specific antibodies (IgG) produced by your immune system in response to HSV-1. These antibodies indicate whether your body has encountered the virus at some point, even if you don’t currently have symptoms.

Your doctor may recommend this test if you have symptoms such as blisters, sores, itching, or unusual discharge around your genitals or mouth, if you have had sexual contact with a partner diagnosed with herpes, or if you are pregnant and want to know your status to protect your baby. It may also be offered as part of screening for sexually transmitted infections when you have certain risk factors.

Your healthcare provider may order this test if you have had cold sores or oral herpes, have unexplained oral sores, or if you’re being evaluated for conditions linked to past HSV-1 exposure, such as certain neurological disorders.

In most cases, no special preparation is needed before this test. You can usually eat and drink normally and continue taking your regular medications, but be sure to tell your healthcare provider about any medicines or supplements you use. A blood sample will be drawn from a vein in your arm, or if you have an active sore, a small swab may be taken from it for testing.

No special preparation is needed. A blood sample will be taken from a vein in your arm by a healthcare professional.

Results are usually reported as positive, negative, or sometimes equivocal, meaning unclear. A negative result generally means there is no evidence of herpes infection, while a positive result suggests past or current infection with HSV-1, HSV-2, or both. Because antibody levels can take several weeks to build up after exposure, your provider may recommend repeating the test to confirm the result and will explain what it means for your health.

A positive result means your body has produced antibodies to HSV-1, suggesting past exposure. A negative result means no detectable antibodies were found at this time, but this does not rule out past infection.