Longitudinal evaluation of herpes simplex virus DNA load during episodes of herpes labialis

Few studies have performed sequential evaluation of the herpes simplex virus (HSV) load using quantitative PCR during episodes of herpes labialis.

To determine HSV viral load kinetics during recurrences of herpes labialis.

Twenty-two subjects were monitored by daily swabs during recurrences of herpes labialis. A real-time PCR detecting both HSV-1 and HSV-2 was used to quantify the viral load.

Median duration of HSV-1 shedding was 60 h and 48 h by PCR and culture, respectively. No HSV-2 DNA was detected in that study. Peak viral DNA load (123.6 copies/cell) occurred at 48 h with no virus detected beyond 96 h of onset of symptoms.

These viral load kinetics data could be used as surrogate markers of antiviral activity in future clinical trials.