Objective: To develop a rapid quantitative real-time polymerase chain reaction (PCR) to detect herpes simplex virus (HSV) in the genital secretions of women that may be used in labor.
Methods: Samples of genital secretions from women in labor, swabs of active genital lesions, and swabs of buffer solution were analyzed using a newly developed rapid HSV PCR assay to detect HSV glycoprotein B gene and quantitate virion copy number. A previously validated TaqMan PCR to detect HSV glycoprotein B gene was performed as the comparator gold standard. Positivity determination that optimized sensitivity and specificity was determined with receiver operating characteristic curves.
Results: The median time to result for rapid HSV PCR was 2 hours (range 1.5-3.5 hours). A positivity determination rule that required both wells of the rapid test to detect 150 copies or greater of HSV per milliliter maximized specificity (96.7%) without appreciable loss of sensitivity (99.6%). Among positive samples, the correlation between the rapid test and TaqMan for the quantity of HSV isolated was excellent (R=0.96, P<.001). The rapid test had a positive predictive value of 96.7% and a negative predictive value of 99.6% in a population with HSV shedding prevalence of 10.8%, based on the prevalence of genital HSV previously found among HSV-2 seropositive women in labor.
Conclusion: Rapid HSV PCR provides results with excellent sensitivity and specificity within a timeframe that could inform clinical decision making for identifying neonates at risk of neonatal HSV infection.
Level of evidence: II.