1流感大流行流感大流行是指当人类流感病毒出现新亚型(包括旧亚型的重现),人群普遍缺乏相应免疫力,造成病毒在人群中快速传播,引起全国、区域或全球范围内的广泛流行。流感大流行具有发病率高、传播迅速和波及范围广的特点,可给人类造成巨大的生命与社会、经济的损失。1.1历史 A flu pandemic flu pandemic refers to the emergence of a new subtype of human influenza virus (including the recurrence of the old subtypes), the general lack of appropriate immunity crowd, resulting in rapid spread of the virus in the population, causing national, regional or global The widespread. Influenza pandemic with high incidence, rapid spread and spread a wide range of characteristics, can cause huge human lives and social and economic losses. 1.1 history