Agent-Based Modelling Laboratory, York University, Toronto, ON M3J 1P3, Canada.
Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT 06510.
Proc Natl Acad Sci U S A. 2020 Apr 21;117(16):9122-9126. doi: 10.1073/pnas.2004064117. Epub 2020 Apr 3.
In the wake of community coronavirus disease 2019 (COVID-19) transmission in the United States, there is a growing public health concern regarding the adequacy of resources to treat infected cases. Hospital beds, intensive care units (ICUs), and ventilators are vital for the treatment of patients with severe illness. To project the timing of the outbreak peak and the number of ICU beds required at peak, we simulated a COVID-19 outbreak parameterized with the US population demographics. In scenario analyses, we varied the delay from symptom onset to self-isolation, the proportion of symptomatic individuals practicing self-isolation, and the basic reproduction number Without self-isolation, when = 2.5, treatment of critically ill individuals at the outbreak peak would require 3.8 times more ICU beds than exist in the United States. Self-isolation by 20% of cases 24 h after symptom onset would delay and flatten the outbreak trajectory, reducing the number of ICU beds needed at the peak by 48.4% (interquartile range 46.4-50.3%), although still exceeding existing capacity. When = 2, twice as many ICU beds would be required at the peak of outbreak in the absence of self-isolation. In this scenario, the proportional impact of self-isolation within 24 h on reducing the peak number of ICU beds is substantially higher at 73.5% (interquartile range 71.4-75.3%). Our estimates underscore the inadequacy of critical care capacity to handle the burgeoning outbreak. Policies that encourage self-isolation, such as paid sick leave, may delay the epidemic peak, giving a window of time that could facilitate emergency mobilization to expand hospital capacity.
在美国出现社区传播的 2019 年冠状病毒病(COVID-19)之后,人们越来越关注治疗感染病例的资源是否充足。医院病床、重症监护病房(ICU)和呼吸机对于治疗重症患者至关重要。为了预测疫情高峰期和高峰期所需的 ICU 床位数量,我们使用美国人口统计学参数模拟了 COVID-19 疫情爆发。在情景分析中,我们改变了从症状出现到自我隔离的延迟时间、自我隔离的症状患者比例以及基本繁殖数。如果没有自我隔离,当 = 2.5 时,在疫情高峰期治疗危重症患者将需要比美国现有 ICU 床位多 3.8 倍。如果在症状出现后 24 小时内有 20%的病例进行自我隔离,那么疫情爆发轨迹将会延迟和变平,从而减少高峰期所需的 ICU 床位数量 48.4%(四分位间距 46.4-50.3%),尽管仍超过现有容量。当 = 2 时,在没有自我隔离的情况下,疫情高峰期将需要增加两倍的 ICU 床位。在这种情况下,自我隔离在 24 小时内对减少高峰期 ICU 床位数量的影响比例高达 73.5%(四分位间距 71.4-75.3%)。我们的估计强调了重症监护能力不足以应对不断增加的疫情爆发。鼓励自我隔离的政策,如带薪病假,可能会延迟疫情高峰期,为扩大医院容量提供紧急动员的时间窗口。