Incidence of serum antibody titers against herpes simplex virus in Japanese patients.

Abstract

Herpes simplex virus (HSV) establishes latency in the sensory neuronal ganglia after primary infection, and occasionally causes recurrent infection, mainly on the lips or genitalia. Previous reports revealed an age-related increase in HSV-immunoglobulin G seropositive subjects in a hospital-based study and the general population in Japan. In this report, we retrospectively analyzed the results of serological tests against HSV, in which subjects were diagnosed with or suspected as having HSV infection. A total of 1216 subjects with at least one complement fixation (CF) result were included. Of these, 771 subjects (63.4%) were positive at first visit. When stratified by age, incidence of positive patients linearly increased with age from teenagers (44.9%) to those in their 80s (88.9%). Positivity in women was higher than in men overall; significantly higher incidence was observed in women aged in their 30s, 40s and 60s. When observing changing HSV-CF titers over time in 81 initially negative patients, 18 (22%) seroconverted during the 2121-day observation period. In this study, we clearly show that distribution of HSV-CF titers is similar to previous HSV-immunoglobulin G results. This correlation is probably caused by the continual subclinical proliferation of HSV, thus maintaining CF titers. Our observations provide current data on the incidence of HSV, reconfirming that serological examination is unreliable in diagnosing recurrent herpes, and the majority of infected subjects are asymptomatic.