BACKGROUND As COVID-19 is integrated into existing infectious disease control programs, it is important to understand the comparative clinical impact of COVID-19 and other respiratory diseases. METHODS We conducted a retrospective cohort study of patients with symptomatic healthcare-associated COVID-19 or influenza reported to the nationwide, hospital-based surveillance system in Switzerland. Included patients were adults (≥18 years) hospitalized for ≥3 days in tertiary care and large regional hospitals. Patients had COVID-19 symptoms and a RT-PCR-confirmed SARS-CoV-2 infection ≥3 days after hospital admission between 1 February 2022 and 30 April 2023, or influenza symptoms and a RT-PCR-confirmed influenza A or B infection ≥3 days after hospital admission between 1 November 2018 and 30 April 2023. Primary and secondary outcomes were 30-day in-hospital mortality and admission to intensive care unit (ICU), respectively. Cox regression (Fine-Gray model) was used to account for time-dependency and competing events, with inverse probability weighting to adjust for confounding. RESULTS We included 2901 patients with symptomatic healthcare-associated COVID-19 (Omicron) and 868 patients with symptomatic healthcare-associated influenza from nine hospitals. We found a similar case fatality ratio between healthcare-associated COVID-19 (Omicron) (6.2%) and healthcare-associated influenza (6.1%) patients; after adjustment, patients had a comparable subdistribution hazard ratio for 30-day in-hospital mortality (0.91, 95%CI 0.67-1.24). A similar proportion of patients were admitted to ICU (2.4% COVID-19; 2.6% influenza). CONCLUSIONS COVID-19 and influenza continue to cause severe disease among hospitalized patients. Our results suggest that in-hospital mortality risk of healthcare-associated COVID-19 (Omicron) and healthcare-associated influenza are comparable.

中文翻译：

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医疗保健相关 COVID-19 （Omicron） 与医疗保健相关流感的院内结果：瑞士的一项回顾性全国队列研究。


背景 由于 COVID-19 已被整合到现有的传染病控制计划中，因此了解 COVID-19 和其他呼吸系统疾病的比较临床影响非常重要。方法 我们对向瑞士全国医院监测系统报告的有症状医疗保健相关 COVID-19 或流感患者进行了一项回顾性队列研究。纳入的患者是在三级医疗机构和大型地区医院住院 ≥3 天的成人 （≥18 岁）。患者在 2022 年 2 月 1 日至 2023 年 4 月 30 日期间入院 ≥ 天出现 COVID-19 症状并经 RT-PCR 确认感染 SARS-CoV-2，或在 2018 年 11 月 1 日至 2023 年 4 月 30 日期间入院 ≥ 天后出现流感症状和 RT-PCR 确认的甲型或乙型流感感染。主要和次要结局分别为 30 天院内死亡率和重症监护病房 （ICU） 收治率。Cox 回归 （Fine-Gray 模型） 用于解释时间依赖性和竞争事件，逆概率加权用于调整混杂因素。结果 我们纳入了来自 9 家医院的 2901 例有症状医疗保健相关 COVID-19 （Omicron） 患者和 868 例有症状医疗保健相关流感患者。我们发现医疗保健相关 COVID-19 （Omicron） （6.2%） 和医疗保健相关流感 （6.1%） 患者之间的病死率相似;调整后，患者 30 d 院内死亡率具有可比的亚分布风险比 （0.91,95% CI 0.67-1.24）。入住 ICU 的患者比例相似（2.4% COVID-19;2.6% 流感）。结论 COVID-19 和流感继续在住院患者中引起严重疾病。 我们的结果表明，医疗保健相关 COVID-19 （Omicron） 和医疗保健相关流感的院内死亡风险相当。