Rocchi G, Ragona G, De Felici A, Muzzi A
Bull World Health Organ. 1974;50(5):401-6.
A statistical study of the mortality from all causes and from respiratory diseases was carried out in an evaluation of the influenza epidemics in Italy from 1956 to 1973. Type A influenzaviruses were responsible for outbreaks every 2-3 years. Type B influenzavirus appeared every 4 years and accounted for a single noteworthy epidemic in 1962-63. From the analysis of data on both general mortality and respiratory mortality a better evaluation of the extent of the influenza outbreaks could be made.
为评估1956年至1973年意大利流感疫情，开展了一项关于全因死亡率和呼吸道疾病死亡率的统计研究。甲型流感病毒每2至3年引发一次疫情。乙型流感病毒每4年出现一次，并在1962 - 1963年引发了一次显著的疫情。通过对总体死亡率和呼吸道疾病死亡率数据的分析，可以更好地评估流感疫情的严重程度。
