Herpes Test - DNA test
Herpes test requires taking a swab sample from the new blisters and the window of opportunity in collecting the sample is very small. This is the most accurate method for confirmation and determination of whether the infection is HSV 1 or HSV 2.
Herpes Test - IgG test
A HSV IgG test can only tell if a person had been infected by HSV 2. For primary infection (first time) which is an early infection, there is not sufficient time for the body to produce IgG and therefore the result will be negative. However, it the symptoms and signs are typical of HSV infection, the test should be repeated in 4-8 weeks to see if the antibody result turns positive.
The sensitivity of HSV 2 IgG test varies greatly. The ELIZA test reagent that we use in our laboratory is EUROIMMUNE which had been shown to have sensitivity >99% in detecting positive IgG level. The best time in performing HSV test is when there are blisters or 4 weeks after at-risk exposure.
However HSV IgG may be tested at 2 weeks after exposure to determine if an infection is a new infection or due to reactivation. Although HSV infection is usually minor and does not lead to major consequence, one should have HSV test before entering into a new relationship and regularly after causal encounters.