The results of the HSV-1 or HSV-2 test might be different from what you expected. If you don’t experience any symptoms or signs you may wonder what can cause a false positive herpes test.
Many STDs tests can produce false-positive results. There is a bunch of reasons.
- If nfection decreases in the person being tested and the test does not identify enough amount of antibodies.
- If you are at low risk of herpes infection (HSV2).
- If you have only HSV1, you may reacive a false positive for HSV2 infection.
- If you have other viruses from the same family like varicella zoster virus (true for IgM tests).
If you couldn’t explain what can cause a false positive herpes test, then it’s worth visiting your family doctor and seeking some advice.
HSV-1 is usually associated with infection in the oropharyngeal area and eyes, while HSV-2 causes mostly genital and neonatal infections. However, the tissue specificity is not absolute, HSV-2 can be isolated occasionally from the oropharynx and 5-10% of primary genital infections may be caused by HSV-1. The antibody of the IgM class is produced during the first 2-3 weeks of infection with HSV and exists only transiently in most patients. Serologic procedures, which measure the presence of IgM antibodies, help discriminate between primary and recurrent infections since IgM antibodies are rarely found in recurrent infections. If present in a sample, high-affinity IgG antibodies to HSV may interfere with the detection of IgM-specific antibodies. High-affinity IgG antibodies may preferentially bind to HSV-1 antigen leading to false-negative IgM results. Also, rheumatoid factor and antigen-specific IgG may bind to IgG, causing false-positive IgM results. This test is CE marked for professional use. For the first time, if the patient is infected in less than 5 days, with no detected specific antibody, the result will be negative when testing.