Often, especially in recurrent cases, symptoms may be so mild as to pass unnoticed or may be absent completely. When a person has an outbreak with no symptoms, this is described as an asymptomatic recurrence. This has important consequences for transmission of the disease. This can then be passed to a sex partner and might infect them. Since the symptoms of a genital herpes outbreak can be absent, or so mild so as to pass unnoticed, the virus can be transmitted without either partner knowing they are infected.
Viral culture looks for the presence of virus in the lesion.
Blood tests can be performed even when no symptoms are present but you should ensure they are type specific. To perform a viral culture, the doctor will use a sterile swab to retrieve a sample from a lesion. A good swab will generally cause some discomfort when a sore or lesion is sampled. The sample is sent to a laboratory where it is grown for several days in a culture of healthy primate cells. If the sample contains herpes, the virus will infect the cells of the culture, causing cellular changes that can be seen with a microscope.