This study investigated the measures taken by medical institutions to prevent the spread of COVID-19 in the Republic of Korea. Through the study, we could identify real-world strategies for controversial areas since no clear guidelines have been established.
All hospitals operated screening clinics, and nearly 90% allowed patients with symptoms not considered to be associated with COVID-19 to enter their general outpatient clinics. Because screening clinics are equipped with minimal facilities and a workforce that can only provide a minimal examination [7], most hospitals manage patients with fever and respiratory symptoms who are unlikely to have COVID-19 at the general outpatient clinic, where careful evaluation and management can be provided. Unfortunately, there are no clear criteria for the entry of symptomatic patients in general outpatient clinics, which can lead to confusion among frontline medical professionals [5]. As observed in this study, many hospitals implemented efficient strategies for patient selection that can be benchmarked by other hospitals, including (i) negative COVID-19 test results within two to three days, (ii) previously treated in general outpatient clinics for a disease related to the current symptoms, and (iii) minimal probability of COVID-19 as determined by experts.
The proportion of asymptomatic patients among COVID-19 cases was about 20–30%, and viral shedding can occur from such patients [8–10]. Because of concerns regarding the transmission of COVID-19 by asymptomatic patients, CDC recommended PCR tests for screening of COVID-19 even for hospitalised patients without COVID-19-related symptoms [11]. A study conducted in long-term care facilities in the United States showed that the prevalence of COVID-19 in facilities that performed broad preemptive PCR tests on inpatients was 0.5%, while it was 28.0% in facilities that did not perform them [12]. Nevertheless, approximately 15% of the hospitals in this study did not perform PCR tests on patients without fever or respiratory symptoms. Although this strategy seems to be effective for detecting asymptomatic COVID-19 patients, its cost-effectiveness remains unproven. Thus, considering the local COVID-19 prevalence, it is necessary to determine whether to proceed with PCR tests when asymptomatic patients are hospitalised [13]. According to the Infectious Diseases Society of America (IDSA), screening asymptomatic patients is expected to be effective in regions with more than 2% prevalence, considering the results of missing a COVID-19 diagnosis and the sensitivity of PCR tests [14]. However, based on the strategy used by many of the hospitals in this study, screening PCR tests for selected patients such as those requiring general anaesthesia, those admitted to the intensive care unit, and those transferred from other medical institutions and nursing homes can be considered in communities with a low prevalence of COVID-19. Furthermore, considering the ongoing COVID-19 vaccination programme in the country and the 95% efficacy of the messenger ribonucleic acid (mRNA) vaccine, limiting PCR tests to unvaccinated patients or caregivers with unclear COVID-19-related symptoms can be a viable option [15].
Three-quarters of the hospitals in the present study implemented preemptive isolation for suspected COVID-19 patients, and most hospitals applied a negative COVID-19 PCR test result as the criterion for release from preemptive isolation. In a single-centre study in South Korea, 350 patients with suspected COVID-19 on the basis of symptoms and epidemiological associations with COVID-19 patients were preemptively isolated, and none of them were confirmed to have COVID-19 [16]. Thus, preemptive isolation for inpatients showing no clear epidemiological association with COVID-19 patients could be considered only in the presence of suspected COVID-19 symptoms or pneumonia in imaging examinations. Since the mean latent period of COVID-19 is 5.2 days after exposure to SARS-CoV-2, even though most hospitals discontinued preemptive isolation after a single negative PCR test result, a second PCR test should be considered for patients with a strong suspicion of COVID-19 [13, 17–19].
Although the probability of infectious SARS-CoV-2 is very low after 10 days from the onset of COVID-19 symptoms in most cases, severely ill or immunocompromised patients can transmit infectious virus particles even after 10 days [18, 20–23], and the continuing possibility of COVID-19 transmission from these hospitalised patients, especially those who need aerosol-generating procedures, has been a topic of concern [22, 24–26]. For these reasons, only 19% of the hospitals treated these patients in a shared room in a general ward regardless of the PCR test results or the time of release from isolation in this survey. Since 50% of patients show positive results in real-time polymerase chain reaction (RT-PCR) tests of nasopharyngeal swabs at around 18 days after the onset of symptoms, and some patients show a positive result even eight weeks later, the inclusion of negative PCR test results in the criteria for release from isolation is likely to lead to unnecessary isolation and excessive use of PPE [26, 27]. Since the cut-off values for quantitative RT-PCR and quantitative immunoassays tend to be correlated with the infectivity of COVID-19, some researchers have suggested that certain cut-off values could be used as surrogate markers for the decision to release hospitalised patients from isolation [22, 28, 29].
Although the current guidelines include many recommendations on PPE for healthcare workers, clear guidelines for the management of healthcare workers were not available. As a result, work-restriction policies for healthcare workers differed across hospitals. Since medical personnel can also spread COVID-19 to other people in medical institutions, many hospitals applied stricter return-to-work criteria than the national guidelines for healthcare workers infected with or exposed to COVID-19. However, strict criteria for returning to work could result in a lack of a sufficient workforce [30]. Thus, the implementation of suitable criteria considering the specificity of the hospitals’ situations is essential.
This study had some potential limitations. First, the survey was conducted in February 2021, and the situation may have changed by the time the results are presented. Second, this survey was performed only in South Korea, and since the prevalence of and social response to COVID-19 differs among countries, additional investigations might be required in other regions or countries. Nevertheless, the findings remain significant since they highlight the importance of appropriate guidelines and indicate key topics relevant to real hospital settings for further research based on the results of this study.