Center for Infectious Disease Modeling and Analysis (Shoukat, Wells, Galvani), Yale School of Public Health, New Haven, Conn.; Canadian Center for Vaccinology (Langley), Dalhousie University, IWK Health Centre and Nova Scotia Health Authority (Langley), Halifax, NS; Emerging Pathogens Institute (Singer), University of Florida, Gainesville, Fla.; Agent-Based Modelling Laboratory (Moghadas), York University, Toronto, Ont.
CMAJ. 2020 May 11;192(19):E489-E496. doi: 10.1503/cmaj.200457. Epub 2020 Apr 8.
Increasing numbers of coronavirus disease 2019 (COVID-19) cases in Canada may create substantial demand for hospital admission and critical care. We evaluated the extent to which self-isolation of mildly ill people delays the peak of outbreaks and reduces the need for this care in each Canadian province.
We developed a computational model and simulated scenarios for COVID-19 outbreaks within each province. Using estimates of COVID-19 characteristics, we projected the hospital and intensive care unit (ICU) bed requirements without self-isolation, assuming an average number of 2.5 secondary cases, and compared scenarios in which different proportions of mildly ill people practised self-isolation 24 hours after symptom onset.
Without self-isolation, the peak of outbreaks would occur in the first half of June, and an average of 569 ICU bed days per 10 000 population would be needed. When 20% of cases practised self-isolation, the peak was delayed by 2-4 weeks, and ICU bed requirement was reduced by 23.5% compared with no self-isolation. Increasing self-isolation to 40% reduced ICU use by 53.6% and delayed the peak of infection by an additional 2-4 weeks. Assuming current ICU bed occupancy rates above 80% and self-isolation of 40%, demand would still exceed available (unoccupied) ICU bed capacity.
At the peak of COVID-19 outbreaks, the need for ICU beds will exceed the total number of ICU beds even with self-isolation at 40%. Our results show the coming challenge for the health care system in Canada and the potential role of self-isolation in reducing demand for hospital-based and ICU care.
加拿大 2019 年冠状病毒病（COVID-19）病例不断增加，可能导致对住院和重症监护的大量需求。我们评估了轻度感染者自我隔离对延迟疫情高峰期和减少每个加拿大省份对这种护理需求的程度。
我们开发了一个计算模型，并模拟了每个省份 COVID-19 爆发的情况。使用 COVID-19 特征的估计值，我们预测了没有自我隔离的情况下医院和重症监护病房（ICU）床位的需求，假设平均有 2.5 例继发病例，并比较了不同比例的轻度感染者在症状出现后 24 小时内进行自我隔离的情况下的情景。
如果不进行自我隔离，疫情高峰期将出现在 6 月上半月，平均每 10000 人需要 569 张 ICU 床位。当 20%的病例进行自我隔离时，高峰期会延迟 2-4 周，与不进行自我隔离相比，ICU 床位需求减少了 23.5%。将自我隔离比例提高到 40%可使 ICU 使用率减少 53.6%，并使感染高峰期再延迟 2-4 周。假设目前 ICU 床位占用率高于 80%，且有 40%的人进行自我隔离，那么需求仍将超过可用（未占用）的 ICU 床位容量。
在 COVID-19 疫情高峰期，即使自我隔离率达到 40%，对 ICU 床位的需求也将超过 ICU 总床位数。我们的研究结果表明，加拿大医疗保健系统即将面临挑战，自我隔离可能在减少对医院和 ICU 护理的需求方面发挥作用。
