In September Roche Diagnostics announced the FDA green-lighted the company’s blood antibody tests for HSV-1 and HSV-2, respectively.
The tests join other “type specific” HSV blood assays on the market that are able to detect the HSV-specific IgG antibody and accurately distinguish HSV-1 antibodies from those of HSV-2. Older, non-specific HSV tests remain available but experts don’t recommend their use.
Viral culture - where a swab of the genital area is taken and the virus is detected in a lab- is another method of diagnosing HSV. This is tricky when no symptoms are present, so for many a blood test is the most practical means of determining their HSV status. (Fewer clinics are offering viral culture, too.) Given that HSV-2 seldom infects other areas of the body, a positive HSV-2 blood test is assumed to reflect a genital infection.
Read more about HSV blood tests at ASHA.