Empiric Acyclovir for Neonatal Herpes Simplex Virus Infection

J Matern Fetal Neonatal Med. 2012 Aug;25(8):1278-82. doi: 10.3109/14767058.2011.629249. Epub 2011 Nov 10.


Background: Because neonatal herpes simplex virus (NHSV) infection is difficult to diagnose, there has been a move towards using more empiric acyclovir (ACV).

Objective: The purpose of this study was to review the use of ACV to optimize future management of NHSV.

Methods: Charts were reviewed for infants started on intravenous ACV up to day 43 of life--January 2001 through February 2007--at five hospitals in Edmonton and Calgary.

Results: ACV was started for possible (N = 115) or proven (N = 3) herpes simplex virus (HSV) infection. Six of the infants with possible HSV infection later had proven HSV infection. Seizures (34%), hemodynamic instability (29%) and skin lesions (24%) were the most common indications for ACV. Among the 118 infants, 106 (90%) had cerebrospinal fluid obtained and 82 (69%) had at least one surface swab for HSV but 4 (3%) had no specimens submitted for HSV detection. ACV was continued for 3.9 ± 3.5 days in the infants with no proven HSV disease. Possible nephrotoxicity from ACV was recorded in 3 of these 109 infants and in none of the infants with proven HSV disease.

Conclusions: Clinicians in Alberta primarily consider the diagnosis of NHSV infection when confronted with a neonate with seizures, hemodynamic instability or suspicious skin lesions, but need to consider the diagnosis more often if all cases are to be treated at first presentation. They often perform incomplete investigations to rule out NHSV infection. Adverse events from ACV appear to be uncommon when the drug is used for suspected NHSV disease.

Publication types

  • Evaluation Study

MeSH terms

  • Acyclovir / adverse effects
  • Acyclovir / therapeutic use*
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use
  • Canada / epidemiology
  • Empirical Research
  • Female
  • Gestational Age
  • Herpes Simplex / congenital*
  • Herpes Simplex / drug therapy*
  • Herpes Simplex / epidemiology
  • Herpes Simplex / transmission
  • Humans
  • Infant
  • Infant, Newborn
  • Infectious Disease Transmission, Vertical / prevention & control
  • Infectious Disease Transmission, Vertical / statistics & numerical data
  • Male
  • Pregnancy
  • Pregnancy Complications, Infectious / epidemiology
  • Retrospective Studies
  • Simplexvirus / drug effects
  • Simplexvirus / isolation & purification
  • Simplexvirus / physiology


  • Antiviral Agents
  • Acyclovir