Persistence of Varicella Zoster Virus DNA in Saliva After Herpes Zoster

TO THE EDITOR—In her otherwise excellent editorial [1], Dr Gershon misinterprets our findings concerning the significance of varicella-zoster virus (VZV) DNA persistence in saliva of patients with zoster, including those with postherpetic neuralgia (PHN) [2]. VZV DNA persistence in saliva of both groups does not indicate that “prolonged replication of VZV is unlikely to explain PHN.” PHN must be explained by functional changes in ganglia, most likely triggered by persistent ganglionitis, as suggested in numerous clinical case reports (reviewed in [3]). Although VZV persists in saliva of many patients with zoster regardless of whether they have PHN, currently it is not possible to correlate virus loads in saliva with chronic ganglionitis in PHN. It is likely that patients with PHN are not able to mount an immune response sufficient to drive VZV back into latency. Our concern is that Dr Gershon’s interpretation will reduce enthusiasm for clinical trials to treat PHN with antiviral agents. This work was supported by grants from the National Institutes of Health (AG032958 to D. G. and R. J. C.; AG006127 to D. G.; and NS067070 to M. A. N.). All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.