The characteristics of severe human parainfluenza virus (HPIV)–associated pneumonia in adults have not been well evaluated. We investigated epidemiologic and clinical characteristics of 143 patients with severe HPIV-associated pneumonia during 2010–2019. HPIV was the most common cause (25.2%) of severe virus-associated hospital-acquired pneumonia and the third most common cause (15.7%) of severe virus-associated community-acquired pneumonia. Hematologic malignancy (35.0%), diabetes mellitus (23.8%), and structural lung disease (21.0%) were common underlying conditions. Co-infections occurred in 54.5% of patients admitted to an intensive care unit. The 90-day mortality rate for HPIV-associated pneumonia was comparable to that for severe influenza virus–associated pneumonia (55.2% vs. 48.4%; p = 0.22). Ribavirin treatment was not associated with lower mortality rates. Fungal co-infections were associated with 82.4% of deaths. Clinicians should consider the possibility of pathogenic co-infections in patients with HPIV-associated pneumonia. Contact precautions and environmental cleaning are crucial to prevent HPIV transmission in hospital settings.

成人严重人类副流感病毒（HPIV）相关肺炎的特征尚未得到很好的评估。我们调查了 2010 年至 2019 年 143 名重症 HPIV 相关肺炎患者的流行病学和临床特征。 HPIV 是严重病毒相关医院获得性肺炎的最常见病因 (25.2%)，也是严重病毒相关社区获得性肺炎的第三常见病因 (15.7%)。血液系统恶性肿瘤（35.0%）、糖尿病（23.8%）和结构性肺疾病（21.0%）是常见的基础疾病。重症监护室收治的患者中有 54.5% 发生合并感染。 HPIV 相关肺炎的 90 天死亡率与严重流感病毒相关肺炎的 90 天死亡率相当（55.2% vs. 48.4%；p = 0.22）。利巴韦林治疗与较低的死亡率无关。 82.4% 的死亡与真菌合并感染有关。临床医生应考虑 HPIV 相关肺炎患者存在致病性合并感染的可能性。接触预防措施和环境清洁对于防止 HPIV 在医院环境中传播至关重要。