Abstract
BACKGROUND: This study aimed to analyze the recent prevalence of neonatal herpes simplex virus infection, maternal symptoms in the presence of neonate who has herpes simplex virus infection, and mode of delivery in Japan. METHODS: We requested 2.078 obstetrical facilities that are members of the Japan Association of Obstetricians and Gynecologists (JAOG) to provide information on neonatal herpes simplex virus infection involving deliveries at or after 22 weeks of gestation between 2020 and 2022. Of these, 1.371 (66.0%) facilities responded with information that could undergo statistical analysis. RESULTS: There were 10 cases of neonatal herpes simplex virus infection, and the incidence of neonatal herpes simplex virus infection in Japan was about 1 in 1.4 × 10(5) live births. There were no characteristic maternal findings common to cases of neonatal herpes simplex virus infection. CONCLUSION: The incidence of neonatal herpes simplex virus infection in Japan was low. We could not identify any characteristic maternal findings common to cases of neonatal herpes simplex virus infection.