Interventions
All researchers are clinical doctors and they will receive standardized training before starting trial. The experimental drug is RDN and the control drug is Oseltamivir. RDN simulant and Oseltamivir simulant have no active ingredients, the former is intravenous drip with normal saline (NS) or grape sugar (GS) avoiding light and the latter is identical with Oseltamivir’s color, flavor and appearance. The detailed method of administration of two groups is shown in Table 
The detailed method of administration of two groups0.5ml/kg/day, maximum is no more than 10ml/day5%GS/0.9%NS diluted 50 ~ 100ml iv drip 30 ~ 40gtt/min q.d.*510ml/day5%GS/0.9%NS diluted 100 ~ 200ml,iv drip, 30 ~ 60gtt/min q.d.*515ml/day5%GS/0.9%NS diluted 200 ~ 250ml,iv drip, 30 ~ 60gtt/min q.d.*520ml/day5%GS/0.9%NS diluted 250ml,iv drip, 30 ~ 60gtt/min q.d.*5

