title: Viral outbreaks in neonatal intensive care units: what we do not know.
abstract: BACKGROUND
  Nosocomial infection is among the most important causes of morbidity, prolonged hospital stay, increased hospital costs, and mortality in neonates, particularly those born preterm. The vast majority of scientific articles dealing with nosocomial infections address bacterial or fungal infections, and viral agents are often disregarded. This analysis reviews the medical literature in an effort to establish the incidence, types of pathogens, and clinical features of noncongenital neonatal viral infections.
  
  
  METHODS
  This analysis was performed using the worldwide database of health care-associated outbreaks (http://www.outbreak-database.com). Items analyzed included causative pathogens, types of infection, source of outbreaks, and measures taken to stop outbreaks.
  
  
  RESULTS
  The outbreak database contained a total of 590 neonatal outbreaks, of which 64 were originated by viruses, 44 of which (68.75%) were reported from neonatal intensive care units (NICUs). The 5 most frequent viral agents were rotavirus (23.44%), respiratory syncytial virus (17.19%), enterovirus (15.63%), hepatitis A virus (10.94%), and adenovirus (9.38%).
  
  
  CONCLUSIONS
  Our analysis of the viral origins of nosocomial infections in NICUs can be a valuable tool in the investigation of neonatal infections. The mortality rates reported in this analysis demonstrate the significance of noncongenital viral infections in NICUs and the need for more effective outbreak prevention strategies.
authors.affiliation: Neonatal Intensive Care Unit, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Civardi
authors.forename: Chryssoula
authors.initials: C
authors.lastname: Tzialla
authors.forename: Fausto
authors.initials: F
authors.lastname: Baldanti
authors.forename: Luisa
authors.initials: L
authors.lastname: Strocchio
authors.forename: Paolo
authors.initials: P
authors.lastname: Manzoni
authors.forename: Mauro
authors.initials: M
authors.lastname: Stronati
mesh_terms: D003428:Cross Infection / Q000453:epidemiology* / Q000401:mortality / Q000821:virology; D004196:Disease Outbreaks; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D016019:Survival Analysis; D014777:Virus Diseases / Q000453:epidemiology* / Q000401:mortality / Q000821:virology*; D014780:Viruses / Q000145:classification / Q000302:isolation & purification*
keywords: Neonate; Noncongenital infection; Nosocomial infection; Virus