脑膜炎球菌和霍乱弧菌一样,可使人在数小时之内死亡。近30年来脑膜炎感染的死亡率并没有变化,仍在10％左右,而其他大多数严重的细菌性或病毒性传染病的死亡率则已明显下降。流行病学地理分布在卫生条件较好的温带国家,流脑是相对少见的,在流行间期每十万居民中患病的少于2～3人。约每7～11年流行的病例增多,在德国,从1940～1970年几乎每7年发生一次流行。在巴西也发现同样的流行规律 Meningococci, like Vibrio cholera, can kill people within hours. The mortality rate of meningitis infections has not changed in the past 30 years and is still about 10%, while the mortality rate of most other serious bacterial or viral infections has dropped significantly. Epidemiology Geographically distributed In temperate countries with better sanitary conditions, meningitis is relatively rare, with less than two to three persons per 100,000 inhabitants during the epidemic. An increase is reported in about 7 to 11 years and in Germany from almost every 7 years from 1940 to 1970. The same prevailing law was found in Brazil