Three-day regimen of oseltamivir for postexposure prophylaxis of influenza in wards.

Inpatients who had been in close contact with patients with influenza were given oseltamivir [75mg capsules once daily for adults or 2mg/kg (maximum of 75mg) once daily for children] for three days as postexposure prophylaxis (PEP). The index patients with influenza were prescribed a neuraminidase inhibitor and were discharged immediately or transferred to isolation rooms. The protective efficacy of oseltamivir for three days was 93% overall [95% confidence interval (CI) 53-99%; P=0.023] and 94% for influenza A (95% CI 61-99%; P=0.017), which is comparable to that of seven- to 10-day regimens of oseltamivir as PEP.