Herpes viral culture of a lesion is a laboratory test to check if a skin sample is infected with the herpes simplex virus.

A sample from a skin lesion (often a genital sore) or blister is needed. The health care provider will collect the sample when you are having an acute outbreak and place it in a laboratory container. The sample must include cells, not just fluid from the blister, since the virus is in the skin cells of the blister or ulcer.

At the laboratory, the sample is placed in a special dish and watched for the growth of the herpes simplex virus, or substances related to the virus. Special tests may also be done to determine whether it is herpex simplex virus type 1 or 2.

Results are available within 16 hours to 7 days, depending on the laboratory method used.

The sample must be collected during the worst part of an outbreak. This is considered the acute phase of infection.

When the sample is collected, you may feel a scraping or sticky sensation. Sometimes a sample from the throat or eyes is needed. This involves rubbing a sterile swab against eyes or over the throat area.

The test is performed to confirm herpes simplex infection. However, the diagnosis is often made by physical examination, rather than diagnostic testing.

A normal result means that the herpes simplex virus did not grow in the laboratory dish. This is a sign that the skin sample is free of such infection.

Abnormal results may mean that you have an active infection with herpes simplex virus. An example of such an infection is herpes genitalis (genital herpes simplex).

Abnormal results may also be due to asymptomatic viral shedding.

Risks include slight bleeding or infection in the area where the skin sample was removed.

Viral culture for herpes is a poor test and is often falsely negative (but extremely rarely falsely positive). That is, even with a negative result, the person could still have herpes.

Newer herpes simplex fluorescent antibody testing may be an alternative. Please consult your doctor.