Australian Army Malaria Research Institute, Enoggera, Queensland, Australia.
Emerg Infect Dis. 2012 Feb;18(2):201-7. doi: 10.3201/eid1802.102042.
Of the unexplained characteristics of the 1918-19 influenza pandemic, the extreme mortality rate among young adults (W-shaped mortality curve) is the foremost. Lack of a coherent explanation of this and other epidemiologic and clinical manifestations of the pandemic contributes to uncertainty in preparing for future pandemics. Contemporaneous records suggest that immunopathologic responses were a critical determinant of the high mortality rate among young adults and other high-risk subgroups. Historical records and findings from laboratory animal studies suggest that persons who were exposed to influenza once before 1918 (e.g., A/H3Nx 1890 pandemic strain) were likely to have dysregulated, pathologic cellular immune responses to infections with the A/H1N1 1918 pandemic strain. The immunopathologic effects transiently increased susceptibility to ultimately lethal secondary bacterial pneumonia. The extreme mortality rate associated with the 1918-19 pandemic is unlikely to recur naturally. However, T-cell-mediated immunopathologic effects should be carefully monitored in developing and using universal influenza vaccines.
在 1918-19 年流感大流行的诸多未解特征中，年轻人（W 型死亡率曲线）的极高死亡率首当其冲。对这一现象以及大流行的其他流行病学和临床表现缺乏一致的解释，导致人们在为未来的大流行做准备时存在不确定性。当时的记录表明，免疫病理反应是年轻人和其他高风险亚组死亡率高的关键决定因素。历史记录和实验室动物研究结果表明，那些在 1918 年之前曾接触过流感的人（例如，A/H3Nx 1890 大流行株），可能对 1918 年 A/H1N1 大流行株的感染产生失调的病理性细胞免疫反应。免疫病理效应会短暂增加对最终致命性继发性细菌性肺炎的易感性。与 1918-19 年大流行相关的极高死亡率不太可能自然重现。然而，在开发和使用通用流感疫苗时，应仔细监测 T 细胞介导的免疫病理效应。
