Analysis of viral DNA in isolates from patients with recurrent herpetic keratitis.

Isolates were obtained from 10 patients with recurrent herpes simplex type 1 infection of the eye, lids, or mouth. The viral DNA of successive isolates from each patients was analyzed by restriction endonuclease fingerprinting. Evaluation of the DNA banding patterns of all isolates by means of two different enzymes, performed in a masked fashion, demonstrated that all of the isolates from any one patient had the same genetic makeup. These results indicate that recurrent herpes infections of the eye and face in humans are caused not by unrelated, serial infections but rather by reactivation of the same latent virus that remains in the ganglion over a period of years.