Abstract
Oseltamivir, recently the most common treatment for influenza in Japan, has been approved for post-exposure prophylaxis against influenza. A few deaths have been reported in children receiving oseltamivir due to suspected neurological causes. This study retrospectively investigated the efficacy of oseltamivir in preventing nosocomial spread of influenza during the past three influenza seasons (October-May) in St. Mary's Hospital. We studied 83 subjects receiving oseltamivir as post-exposure prophylaxis in 2004/05, 57 subjects in 2005/06, and 42 subjects in 2006/07. The subjects received oral oseltamivir capsule once daily for 5 or 7 days. The rates of subjects who developed influenza decreased from 13.3% in 2004/05, to 3.5% in 2005/06, and 2.4% in 2006/07. The usage of oseltamivir decreased markedly in the 2006/07 season. The rates of rapid influenza antigen detection and vaccination coverage among the staff were similar in all seasons. No significant adverse effects due to oseltamivir were observed in the subjects. Effective use of post-exposure prophylaxis of oseltamivir requires early detection and treatment.
