Genesis, evolution and effectiveness of Singapore's national sorting logic and home recovery policies in handling the COVID-19 Delta and Omicron waves

Joachim Wen Kien Yau, Martin Yong Kwong Lee, Eda Qiao Yan Lim, Janice Yu Jin Tan, Kelvin Bryan Jek Chen Tan, Raymond Swee Boon Chua, Joachim Wen Kien Yau, Martin Yong Kwong Lee, Eda Qiao Yan Lim, Janice Yu Jin Tan, Kelvin Bryan Jek Chen Tan, Raymond Swee Boon Chua

Abstract

Singapore developed several novel strategies to transition towards "living with COVID-19", while protecting hospital capacity. The Home Recovery Programme (HRP) was a national, centrally-administered programme that leveraged technology and telemedicine to allow low-risk individuals to safely recover at home. The HRP was subsequently expanded by partnering primary care doctors in caring for more cases in the community. A key enabler was the National Sorting Logic (NSL), a multi-step triage algorithm allowing risk-stratification of large numbers of COVID-19 patients at a national-level. At the core of the NSL was a risk assessment criterion, comprising of Comorbidities-of-concern, Age, Vaccination status, Examination/clinical findings and Symptoms (CAVES). The NSL sorted all COVID-19 cases into the various levels of care - Primary Care, HRP, COVID-19 Treatment Facility and Hospital. By adopting a national approach towards managing healthcare capacities and triaging COVID-19 patients, Singapore was able to prioritize healthcare resources for high-risk individuals and prevent hospital capacities from being overwhelmed. As part of the national response strategy to tackle COVID-19, Singapore set up and integrated key national databases to enable responsive data analysis and support evidence-based policy decisions. Using data collected between 30 August 2021 to 8 June 2022, we conducted a retrospective cohort study to evaluate the outcomes and effectiveness of vaccination policies, NSL and home-based recovery. A total of 1,240,183 COVID-19 cases were diagnosed during this period, spanning both Delta and Omicron waves, Overall, Singapore experienced very low severity (0.51%) and mortality (0.11%) rates. Vaccinations significantly lowered severity and mortality risks across all age groups. The NSL was effective in predicting risk of severe outcomes and was able to right-site >93% of cases into home-based recovery. By leveraging high vaccination rates, technology and telemedicine, Singapore was able to safely navigate through two COVID-19 waves without impacting severity/mortality rates nor overwhelming hospital capacities.

Keywords: COVID-19; Delta; Home recovery; Mortality; Omicron; Primary care; Severity rates; Sorting logic; Technology; Telemedicine; Triage criteria.

Conflict of interest statement

The authors have no conflict of interests to declare.

© 2023 The Author(s).

Figures

Fig. 1
Fig. 1
5-stepnational sorting logic with embedded age-vaccination risk matrix and online questionnaire.
Fig. 2
Fig. 2
Total daily new COVID-19 cases and 7-day moving average.

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Source: PubMed

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