Journal Archive

The World Health Organization (WHO) announced in May 2023 that the status of COVID-19 had transitioned from a public health emergency of international concern, initially declared in January 2020, to a continuing health threat (WHO, 2023). Nevertheless, the WHO highlighted that the global population has yet to completely escape the public health risks caused by COVID-19 and advised ongoing preventive measures for effective risk response even after the emergency situation was lifted (WHO, 2023).

At the onset of the outbreak, when the virus was not well understood, the rapid increase in patients led to issues like a shortage of beds and disparities in medical resources, and it was pointed out that isolation measures were needed for mild patients who account for 80% of all patients (Ministry of Health and Welfare, 2020a).

Facility-based isolation is widely used in South Korea, China, and Singapore (Chen et al., 2021). In South Korea, many isolation facilities called “residential treatment centers (RTCs)” were introduced to manage patients from the early stage of COVID-19.

The RTC is an independent medical facility that was operated separately from conventional hospitals. Its purpose is to isolate and monitor individuals with mild symptoms, thereby conserving advanced medical resources and mitigating the risk of disease transmission. It has been evaluated as a successful initiative in distributing medical resources during a crisis (Park et al., 2020). In Korea, RTCs are classified into two types: central and local. The national government operates the central type and serves patients on a regional level by collaborating with two or three neighboring local governments. In contrast, the local type is managed by individual local governments and accommodates patients from their respective jurisdictions. Candidate facilities for RTCs include both public and private establishments, such as educational and training facilities, university dormitories, and hotels. These facilities are designated as RTCs based on consultations and private facilities were paid a certain fee for using them as RTCs.

Despite such achievements and necessity, significant challenges were encountered in securing facilities for RTCs due to issues like resident protests, inequitable distribution of facilities, patient transfer, and conflicts during negotiations for utilizing private facilities. For instance, resident protests have been a contributing factor in delaying the opening of RTCs, regardless of whether the facilities were publicly or privately owned. In order to secure the requisite number of beds to accommodate a rapidly increasing patient population, both public and private facilities were concurrently considered. Subsequently, those facilities that received owner approval were officially designated as RTCs. The number of beds in RTCs was increased to accommodate the growing number of patients, recorded as 10,808 on December 22, 2020, 17,764 on December 21, 2021, and 20,244 on March 5, 2022 (Ministry of Health and Welfare, 2022).

Through the experiences of dealing with COVID-19, it was recognized that the impacts of infectious diseases are not limited to the health and medical sectors but can pervade society. Therefore, it was underscored that the importance of securing facilities for preventing the spread of infectious diseases as social capital is crucial for preparing for potential future uncertainties (Ha, 2020).

Since the 1970s, over 30 major novel infectious diseases have been discovered, and new infectious diseases continue to emerge (Chun, 2015). Due to continuing globalization and urbanization, the spread of such novel infectious diseases could potentially occur at any time (Jo, 2020).

In this regard, it is necessary to identify local resources that can be promptly allocated for emergency healthcare, such as isolation and treatment when an infectious disease outbreak occurs, and to seek a utilization system including resource allocation and scheduling based on local infection trends and characteristics.

This study suggests a model for the location and scheduling of isolation facilities, which are an essential element of disaster management resources, in response to infectious diseases with characteristics of community spread. To achieve this, we first investigated the distribution of facility resources utilized as isolation facilities and made the list of candidate list for isolation facilities. Secondly, we develop the facility location and scheduling model using optimization techniques.

In the wake of the COVID-19 outbreak, research on the location and capacity design of emergency facilities has garnered significant attention. Researchers have striven to formulate effective and resilient facility locations, such as testing and vaccination facilities, hospital operations, and casualty transportation (Liu et al., 2023; Rautenstrauss et al., 2023; Risanger et al., 2021; Shaker Ardakani et al., 2023; Taiwo, 2021; Thul and Powell, 2023; Yin et al., 2023).

We concentrate on the problem of locating and scheduling isolation facilities, considering effective operating costs and patient dispatching distances. There are numerous prior studies concerning temporary facility location and casualty allocation planning in the context of health emergencies like disease outbreaks and natural disasters (Devi et al., 2022; Liu et al., 2019; Sun et al., 2021; Verma and Gaukler, 2015). For instance, Verma and Gaukler (2015) proposed disaster response facilities for emergency supply storage during an earthquake to minimize transportation costs under the constraint of a limited number of facilities. Kongsomsaksakul et al. (2005) proposed a location-allocation model for flood evacuation shelters considering the decision of authorities and evacuees.

While these studies assumed fixed demands for facilities, situations like pandemics often require the selection of locations considering factors such as cost and time (Boonmee et al., 2017). Consequently, a dynamic facility location problem has been proposed for temporary facility planning. Given the dynamic nature of COVID-19 and the changing demands for facilities, addressing the dynamic change of demands becomes a critical issue. Hosseini-Motlagh et al. (2023) suggested COVID-19 control strategies by locating screening facilities, health facilities, and isolation facilities in order to minimize transmission rates, taking into account factors such as positive rates, underlying conditions, and death rates. Aydin and Cetinkale (2023) considered the scenario of a large-scale earthquake occurring during an ongoing pandemic and proposed a model for determining the necessary number and location of temporary healthcare facilities based on a revised compartmental model for COVID-19 transmission.

Based on the previous literature, this study made three primary contributions. Firstly, this study developed a model for the location and operating schedule of isolation facilities, taking into account dynamic patient needs. Although some studies have proposed facility location models that consider dynamic changes in demands, these models assume that the assigned facilities operate throughout the entire period. In contrast, in countries like Korea, patients with mild symptoms were isolated outside hospitals, utilizing both private and public facilities, with varying operating periods based on infection numbers (Yang et al., 2020). Thus, the effective operation of isolation facilities necessitates flexibility in response to infection trends.

Secondly, our model considered both facility conditions (capacity, ownership, and staff) and accessibility. Especially, considering accessibility is a significant challenge due to the lack of location information for patients at a fine-grained spatial scale. Many countries collect patient information at the city level, and infection predictions have been conducted at the city or county level. Our model considered the mean accessibility, taking into account the spatial distribution of RTCs and population, and makes it possible to strike a balance between facility cost and patient accessibility.

Thirdly, we identified the critical RTCs necessary for effective isolation, considering different infection scenarios and operation strategies. Allam and Jones (2020) emphasized urban restructuring focusing on emergency preparedness to control pandemics and showed that many cities constructed new medical facilities to increase the capacity for handling emergency cases. Identifying important and critical RTCs for infectious disease management makes it possible to respond rapidly based on prior consultations and prevent the decrease in the functioning of cities.

In the wake of COVID-19, the importance of effective isolation facilities for mild symptomatic patients has been underscored. While countries like South Korea have implemented strategies such as RTCs, significant challenges remain in securing suitable facilities and effectively operating them. In this study, we propose a model for allocating and operating isolation facilities in response to community spread infectious diseases. This study had four main findings.

First, we suggested a facility location and scheduling model in consideration of dynamic patient needs and facility operating periods. Unlike traditional models that operate under static assumptions, our model recognizes that disease spread is a dynamic process with evolving demands. Hence, it provides scheduling of facility operations based on the projected number of confirmed cases, ensuring an efficient and responsive allocation of resources. Also, the suggested model can be introduced in geographic contexts.

Second, we provided criteria for the selection of suitable facilities to be utilized as RTCs from a wide range of facilities available in the local community. Considering that RTCs function as isolation facilities, our criteria primarily focused on the suitability of the building usage for individual isolation purposes. Furthermore, we took into account the entire process of securing, converting, and operating facilities as RTCs, which led us to establish selection criteria based on the ownership status of the facilities to ensure ease of acquisition and conversion, as well as the facility size to optimize operational efficiency. These criteria can serve as valuable guidelines for implementing a similar approach in different regions.

Third, our model provides a strategic approach to the trade-offs that occur in resource allocation, considering both facility cost and accessibility. These trade-offs can manifest as conflicts between the ease of conversion of a facility and its location, or between operating costs and patient convenience. By quantifying these variables and incorporating them into an objective function, our model offers an analytical way to navigate these trade-offs and arrive at optimal solutions. Especially, our model can consider the accessibility of patients by introducing a mean accessibility that accounts for both population and facility distributions, even in the absence of fine-grained location information.

Fourth, this study identified critical facilities considering different scenarios and strategies. Our result highlighted that while public facilities have advantages in terms of accessibility and conversion, private facilities can be critical in ensuring effective response, especially in the early stages of infection spread, to avoid resource inefficiencies. Urban planning emerged as a response to public health problems, including epidemics. Urban restructuring focusing on emergency preparedness to control pandemics is important to prevent the decrease in the functioning of cities. Identifying important and critical RTCs can contribute to urban planning for securing public health. However, the actual process of securing private resources for Residential Treatment Centers (RTCs) often entails legal and administrative complexities, emphasizing the need for advanced planning and coordination. If local governments can proactively identify private facilities suitable for conversion into RTCs and designate them as “disaster management resources” based on the Framework Act On The Management Of Disasters And Safety, their response measures are likely to be more effective in emergency situations.

However, this study has several limitations. The modeling parameters were simplified due to insufficient information and computational efficiency. For example, the operating cost based on the operation history can improve the reality of the model. Additionally, the study only considers patients with mild symptoms, whereas, in reality, the emergency supply chain considering the connection between RTCs and hospitals, is required to respond to different symptom severity. Lastly, considering inter-municipal cooperation is necessary to apply our model to small cities that manage patients at the provincial level due to a lack of facilities and staff at the city level.