某些传染病常出现周期性流行,其主要原因是 ( )A.传播途径的改变B.传染源的积累C.易感人群的积累D.病原体抗原性的变异E.自然因素周期...

作者: rantiku 人气: - 评论: 0
问题 某些传染病常出现周期性流行,其主要原因是 ( )
选项 A.传播途径的改变 B.传染源的积累 C.易感人群的积累 D.病原体抗原性的变异 E.自然因素周期性的改变
答案 C
解析

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  • 消息: [程序异常] : MISCONF Redis is configured to save RDB snapshots, but it's currently unable to persist to disk. Commands that may modify the data set are disabled, because this instance is configured to report errors during writes if RDB snapshotting fails (stop-writes-on-bgsave-error option). Please check the Redis logs for details about the RDB error.
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