Acute lower respiratory infections (ALRI), encompassing bacterial and viral pneumonias, acute viral bronchiolitis, and bacterial and viral bronchitis, remain the leading cause of global child mortality. The thrust of global prevention and treatment efforts has been directed against bacterial causes of ALRI, and deaths from bacterial pneumonia have decreased substantially since 1990 because of improved access to health care and life-saving antibiotics, as well as increased use of vaccines targeted at bacterial respiratory pathogens. The leading causes of ALRI now are viral infections, with respiratory syncytial virus, influenza virus, parainfluenza virus, rhinovirus, and human metapneumovirus among the top viral causes of ALRI in children, particularly in low-resource settings. Prevention and treatment of viral pathogens could therefore substantially affect childhood ALRI outcomes.

中文翻译：

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资源匮乏地区幼儿病毒性呼吸道感染的负担。

急性下呼吸道感染 (ALRI)，包括细菌性和病毒性肺炎、急性病毒性细支气管炎以及细菌性和病毒性支气管炎，仍然是全球儿童死亡的主要原因。全球预防和治疗工作的重点是针对 ALRI 的细菌原因，自 1990 年以来，由于获得医疗保健和挽救生命的抗生素的机会得到改善，以及针对细菌的疫苗的使用增加，细菌性肺炎导致的死亡人数大幅下降呼吸道病原体。现在 ALRI 的主要原因是病毒感染，呼吸道合胞病毒、流感病毒、副流感病毒、鼻病毒和人偏肺病毒是儿童 ALRI 的主要病毒原因，特别是在资源匮乏的环境中。