A Multicenter Study on Symptomatic Neonatal Herpes Simplex Virus Infection in Korea From 2008 to 2017

Background: Neonatal herpes simplex virus (HSV) infection is rare but can cause severe disease, even death. However, data on neonatal HSV infection is limited in Asia. Thus, this study estimated the incidence of neonatal HSV infections and evaluated the characteristics in hospitalized patients in Korea, where seroprevalence of HSV infection in child-bearing age women is not well known. Methods: This is the first multicenter retrospective study in 12 university hospitals in Korea. Neonates aged ≤ 28 days with confirmed HSV infection were identified from January 2008 to December 2017, and a chart review was performed. Results: Among 12 medical centers, 16 patients were identified in 6 centers. The estimated incidence rate was 1/7,888 in hospitalized neonates. Eight (50%) patients were males, and the median age at diagnosis was 11 days (range, 4–28 days). Ten (62.5%) patients were HSV-1positive, and 6 (37.5%) patients were HSV-2-positive. Four (25%) patients had disseminated infection, 11 (68.8%) patients had central nervous system disease, and 1 (6.2%) patient had skin, eye, and/or mouth disease. All the patients received intravenous acyclovir, with a median treatment duration of 19 days (range, 3–68 days). Four (25%) patients received additional oral acyclovir suppressive therapy, with the median treatment duration of 5 months (3–6 months). Four patients (25%) developed seizures (one case with disseminated disease and 3 cases with central nervous system disease), and 2 of them recovered without neurologic complications. Two (12.5%) patients with disseminated disease died within 30 days from the diagnosis, and one of them had a maternal history of previous genital herpetic lesions. Medical records of maternal genital herpes were not available in 10 (62.5%) patients with neonatal HSV infections. Conclusion: Although uncommon, neonatal HSV infection occurs in Korean babies with a high 30-day mortality of 12.5%. Increased awareness is warranted among Korean pediatricians for the early diagnosis and treatment of neonatal HSV infection.