Define asymptomatic shedding.

In individuals previously infected with HSV, virus may periodically be present at the site of infection in the absence of clinically evident lesions. This is referred to as asymptomatic shedding. During asymptomatic shedding, the presence of virus may be documented by viral culture or polymerase chain reaction (PCR). Although the viral titer is lower than during clinically active disease, transmission of the virus can nevertheless occur. In fact, contact during periods of asymptomatic shedding is thought to be responsible for many cases of disease transmission.