Relationship between serum anti-varicella zoster virus antibody titer and time from onset of herpes zoster.
Herpes zoster is an internal reactivation of varicella zoster virus, and its onset depends on immunity against this virus. We have previously reported that antiviral antibody titers are inversely correlated with patient numbers. In this study, we hypothesized that patients with higher titers may be late visitors to the clinic, whose antibodies were already boosted at presentation because of the time lapse between onset of zoster and measurement of antibodies. We analyzed antibody titers of patients with acute herpes zoster who visited Fukuoka University Hospital from January 2009 to May 2016 (n = 141, 62 males and 79 females). Varicella zoster virus-specific immunoglobulin G, M and complement fixation tests were positive in 93.9%, 12.0% and 64.2% of the patients, respectively. Immunoglobulin G and complement fixation titers were strongly correlated (Spearman's r = 0.8634, P < 0.0001). Patients with high immunoglobulin G and complement fixation titers were immunoglobulin M-negative. Unexpectedly, immunoglobulin G and complement fixation titers showed large inter-subject variation, and were only weakly correlated with onset-measurement time lapse. Patients with consecutive tests tended to show increasing immunoglobulin G and complement fixation titers. Our data suggest that herpes zoster preferentially occurs in patients with low immunoglobulin G and complement fixation titers, and subsequently causes antibody elevation. However, the timing of elevation varies and can be as late as 10 days after zoster. The large variation in antibody titer over the time from onset to testing suggests that some mechanism exists that resists the local breakthrough of virus in the skin, and so delays the onset of blisters.