Recurrent intraoral herpes simplex virus infection.

A 48-year-old female had primary herpetic gingivostomatitis, followed by recurrent intraoral herpes simplex virus (HSV) disease; HSV isolates were obtained from the swabs of primary and recurrent lesions; restriction endonuclease cleavage analysis of the viral DNAs extracted from Vero cells infected with the HSV isolates according to the method of Hirt was carried out. The viral DNAs were cleaved by restriction endonucleases such as BamHI, KpnI and SalI and resolved by agarose gel electrophoresis, followed by staining with ethidium bromide. Consequently, their cleavage patterns were very similar to one another and were identified as HSV type 1. From these findings, it can be concluded that primary and recurrent lesions of this case are caused by the same virus.