Domestic airline travel in November was the best predictor of the speed of influenza spread, the researchers found, although influenza infections and deaths usually peak in late February.

• 研究者发现,虽然流感的传染和死亡通常在二月末才达到高峰,但十一月的国内飞机旅行却能为流感的传播速度作最好的预警。