title: Survey of Japanese infants younger than 3 months who were treated with oseltamivir for influenza: safety of oseltamivir treatment.
abstract: BACKGROUND
  Young infants with influenza virus infection are frequently hospitalized, and are at risk of serious complications including death. With the emergence of pandemic influenza A/H1N1 2009, oseltamivir was approved for use in Europe and the USA, including use in infants aged < 3 months. However, few data are available regarding the safety of oseltamivir treatment for influenza in infants aged < 3 months.
  
  
  METHODS
  The clinical data from Japanese infants aged < 3 months with laboratory-confirmed influenza virus infections, who were treated with oseltamivir between October 2009 and April 2011, were collected and analyzed.
  
  
  RESULTS
  Forty-four infants were included in the study. The median age was 1 month (range 4 days to 2 months) and median body weight was 4.5 kg (range 2.6-7.6 kg). Thirty-eight infants (86%) had no underlying diseases. The most common presenting symptom was fever (42 infants, 95%). There were no cases of influenza-associated encephalopathy or myocarditis. The median time between the onset of influenza symptoms and initiation of oseltamivir treatment was 0 days (range 0-7 days), with treatment initiated within 1 day in 40 infants (91%). The oseltamivir dose was 1.5-2 mg/kg twice daily in 98% of infants. No serious adverse events were identified during treatment. All infants recovered completely.
  
  
  CONCLUSIONS
  Treatment of influenza with oseltamivir 1.5-2 mg/kg twice daily may be safe in infants aged < 3 months.
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan. ichim@med.kobe-u.ac.jp
authors.forename: Ichiro
authors.initials: I
authors.lastname: Morioka
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Nonoyama
authors.forename: Keiko
authors.initials: K
authors.lastname: Tanaka-Taya
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Ihara
authors.forename: Norio
authors.initials: N
authors.lastname: Sugaya
authors.forename: Ikuya
authors.initials: I
authors.lastname: Ueta
authors.forename: Takuji
authors.initials: T
authors.lastname: Kumagai
authors.forename: Kenji
authors.initials: K
authors.lastname: Okada
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Hosoya
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Okabe
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Morishima
mesh_terms: D000998:Antiviral Agents / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification; D007251:Influenza, Human / Q000188:drug therapy* / Q000821:virology; D007564:Japan; D053139:Oseltamivir / Q000009:adverse effects* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D053139:Oseltamivir