Background: A sensitive and specific method for detecting herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) is important for diagnosing genital and cutaneous infections.
Goal: The goal of this study was to compare quantitative real-time polymerase chain reaction (qPCR) with virus culture for diagnosis of genital and cutaneous HSV-1 and HSV-2.
Study design: A duplex qPCR system for quantification of DNA from HSV-1 and HSV-2 was developed. Duplicate swabs for PCR and virus culture were collected from 89 patients attending our sexually transmitted infection and dermatology clinic.
Results: The duplex qPCR had a linear measure interval of 10-10 copies/mL. The detection limit was between 1 and 5 copies per reaction. qPCR detected HSV in 57 (64%) specimens and virus was isolated in 45 (50%) cases. First-episode infections showed higher viral quantities with a median value of 4.2 x 10 copies per reaction compared with recurrent infections with 1.0 x 10 (P = 0.0002). HSV-1 was more likely to be the cause of first-episode genital infections (72%), and HSV-2 of recurrent and atypical genital manifestations (73%).
Conclusion: Real-time PCR is a sensitive method for diagnosing genital herpes, and the duplex format is convenient for typing. The method increased the detection rate by 27% compared with virus culture.