PCR analysis of 16 specimens from categories A, B, C, and D with nontyping (primer set 1) and typing (primer set 2) HSV primer sets. (A) PCR with HSV primer set 1 and an exposure time of 4 h; 100 and 10, numbers of copies of HSV DNA; H2O, reagent control; and − and +, viral transport medium controls without and with 1 PFU of HSV-2, respectively. (B) PCR with HSV primer set 2 and an exposure time of 4 h; U, PCR product only; C, PCR product treated with BamHI. (C) Extended exposure time of the autoradiograph (17 h) in panel B to enhance visualization of specimens 4, 5, 15, and 16.