COVID-19 Pandemic
Modeling Study Impact of Lifting Isolation Measures on COVID-19 Infected Individuals in South Korea Suyoung Jo* Suyoung Jo Kyung-Duk Min Sung-il Cho
From the early stages of the COVID-19 pandemic, South Korea effectively controlled incidence and mortality through the TTIQ strategy. Starting in 2022, the country gradually lifted isolation periods, reflecting an exit strategy that balanced public health and socioeconomic burdens. This study evaluated the impact of lifting isolation measures on COVID-19 control in South Korea from both perspectives.
A deterministic mathematical model for SARS-CoV-2 transmission dynamics was developed using data from the Korea Disease Control and Prevention Agency (KDCA) on daily age-specific confirmed cases and vaccination rates (January 16, 2022, to August 31, 2023) and population data from Statistics Korea for 2021. The V-SEIR model was parameterized using prior literature and calibration.
In 2022, scenarios compared reducing isolation from 10 to 7 days (starting February 10) with maintaining 10 days, reducing it to 5 days, or delaying the reduction by two months. In 2023, scenarios assessed lifting isolation on June 1 against earlier or later dates. Outcomes were compared with the strictest scenarios using additional cases and economic savings calculated via average daily wages. Cost-effectiveness was assessed using the Incremental Cost-Effectiveness Ratio (ICER).
Results showed that in 2022, delaying the reduction by two months minimized cases, but the real-world scenario yielded the greatest economic savings, saving $4,341 per case and making it the most cost-effective. In 2023, lifting isolation one month later than the real-world scenario saved $244 per case, proving more cost-effective.
This study highlights the importance of adjusting isolation policies based on population immunity and economic activity to optimize policy outcomes. These findings underscore the critical importance of timing in lifting isolation measures to effectively mitigate trade-offs between public health and socioeconomic burdens, offering evidence-based insights for future decision-making.