Antiviral treatment for influenza in Japan.

Anti-influenza drugs reduce the viral load, which leads to improvement of symptoms, a reduced illness period, suppression of complications, and protection from transmission. It is desirable to administer antiviral drugs within 48 h of the onset of symptoms. The use of antiviral drugs is limited mainly to individuals who are hospitalized, those who have severe, complicated, or progressive illness, or those who are at high risk for influenza complications in western countries. On the other hand, in Japan, anti-influenza drugs have been widely used from the onset of the disease by general practitioners in order to ease symptoms, that leads to suppressed development of severe complications. Five drugs for influenza are available in Japan at present, which is thought to be that influenza treatment in Japan is the advanced one in the world. Baloxavir, the newest anti-influenza drug which has different mechanism from neuraminidase inhibitors rapidly reduce viral loads. Baloxavir is recommended as oseltamivir for the treatment of influenza.