Experience with oseltamivir in term and preterm newborns

Since April 2009 in Mexico, a novel influenza virus A (H1N1) of swine origin has emerged as a cause of disease in humans, and has rapidly spread worldwide, declared a pandemic on June 11. Oseltamivir is the only anti-viral agent available for influenza virus in young children, with no proven efficacy and safety in infants and newborns. The authors report their experience with oseltamivir use for term and preterm neonates, during an outbreak of influenza virus A (H1N1) in a level III neonatal intensive care unit, from November 28 to December 7, 2009. Fifteen hospitalized high risk neonates of non-vaccinated mothers, 6 males and 9 females; gestational age 34 weeks (24-40 weeks); birth weight 1873 g (530-3310 g); 12 became infected with influenza virus A (H1N1); two were (17%) symptomatic. Infection control measures were adopted and oseltamivir was administered after parental consent; for prophylactic use in three (3 mg/kg once a day, 10 days); and therapeutic use in 12 (3 mg/kg twice a day, 5 days). No fatal cases occurred. No adverse effects were reported. The outcome was favorable and the outbreak controlled. The majority of patients infected with influenza virus A (H1N1) were asymptomatic, and no fatal cases were documented. Oseltamivir was not associated with evident short-term adverse effects, and it may have helped to control the epidemic and lessened the severity of illness in affected infants.