The sudden onset, dramatic symptoms, and rapid deterioration of patients, and the absence of a vaccine and effective treatment, invariably incite great anxiety in affected populations.

突然发病、显著症状、患者病情迅速恶化以及缺乏疫苗和有效治疗，常常引起受感染人群的巨大焦虑。

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Absence of symptoms does not mean the absence of stress.

没有症状并不意味着没有压力。

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One additional family member, who had been hospitalized, has subsequently been ruled out based on both negative laboratory results and the absence of clinical symptoms compatible with H5N1 infection.

另一名家庭成员已住院，随后根据阴性实验室结果和没有与H5N1感染相一致的临床症状已被排除。

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