Lab Testing Options
Laboratories generally offer viral culture and blood serology tests. Healthcare providers rely on the laboratory to provide diagnostic test results and information. Visual diagnosis of presenting lesions is not accurate enough to diagnose genital herpes.
Type-specific serology tests distinguish between HSV-1 and HSV-2 antibodies. Purified HSV type-specific antigens gG1 and gG2 can be used to detect HSV type-specific IgG antibodies. Sera from individuals infected with only HSV-1 will react primarily with gG1. Sera from individuals infected with only HSV-2 will mainly react with gG2.
There are several type-specific ELISA (enzyme immunoassay) tests commercially available that are relatively easy to perform in the laboratory and give results quickly. Type-specific assays for HSV antibodies are based on the HSV-specific glycoprotein G2 for HSV -2 and glycoprotein G1 for HSV-1.
HerpeSelect tests from Focus Diagnostics, are available in multiple formats for detecting type-specific HSV IgG antibodies:
Serology tests involve the detection of antibodies to herpes simplex virus (HSV) in the blood. Type-specific and nonspecific antibodies to HSV often develop during the first several weeks following infection and remain in the blood indefinitely. Some patients may not develop antibodies for up to 6 months.
During primary infection, the first antibodies produced belong to the IgM class. The presence of IgM antibodies in HSV infections is difficult to interpret and may be confusing. The presence of IgM antibodies may indicate a primary infection, a super-infection with the other serotype, or reactivation of a latent HSV infection, (HSV-1 or HSV-2). For this reason, IgM testing is not recommended as a diagnostic tool.
Type-common (crude antigen) serology tests measure HSV antibodies in the blood but are often unable to distinguish between HSV-1 and HSV-2 infection. Most adults have HSV-1 antibodies, so crude antigen tests ability to detect HSV-2 infections is questionable.