Coronavirus disease 2019 (COVID-19) is a respiratory syndrome caused by SARS-CoV-2 infection that has spread rapidly around the world. The World Health Organization (WHO) declared a pandemic in March 2020, and South Korea downgraded the infectious disease classification of COVID-19 from level 1 to level 2 in April 2022 [1]. In May 2023, as the WHO lifted the ‘Public Health Emergency of International Concern’ for COVID-19, Korea also declared the end of the pandemic [2].

Personal hygiene has been emphasized since the COVID-19 pandemic, but this can increase the possibility of hypersensitivity, extreme behavior, obsessive-compulsive disorder, or worsen the disease [3]. Nurses reported anxiety, fear, stress, and depression about themselves, their family members, and acquaintances being infected or spreading COVID-19 [4]. This may lead to psychological obsession with COVID-19.

Obsession with COVID-19 refers to an individual’s excessive and repetitive thoughts about COVID-19 [3]. Accordingly, a tool was developed to measure how much thoughts about COVID-19 occur while exposed to the ongoing COVID-19 pandemic [5]. This is an anxious thought that oneself or someone around oneself may be infected with COVID-19, and is related to anxiety, obsessive-compulsive disorder, and depression [6]. An international study reported that 19.4% of 248 doctors and nurses had problematic symptoms related to COVID-19 between October 2020 and May 2021 [7]. In a domestic study conducted on 137 nurses in August 2022, 14.6% were reported as potentially not thinking normally [8]. Although COVID-19 has been lowered to the ‘alert’ management level [2], healthcare institutions continued to receive confirmed COVID-19 cases. Therefore, nurses were exposed to COVID-19 at all times as they are performing COVID-19 infection control tasks in addition to their daily basic nursing duties. In other words, there is a need to identify factors affecting nurses’ obsession with COVID-19, as they are likely to continue to treat COVID-19 patients even after the pandemic.

Posttraumatic growth (PTG) refers to positive psychological changes that an individual experiences after experiencing a traumatic event [9]. Most people who experience trauma do not show posttraumatic stress disorder, which is a negative outcome, and some show changes by experiencing PTG, which is a positive outcome [10]. In a domestic study, the PTG of nurses who cared for COVID-19 patients was 46.5 points out of 80 [11] and 37.0 points [12]. PTG may have positive effects on nurses who have experienced the COVID-19 pandemic, such as changes in cognition, interpersonal relationships, outlook on life, and optimism [13], which may affect the reduction of anxiety or fear of COVID-19 and thus reducing excessive and repetitive thoughts. However, the number of studies conducted is still small, and most studies were measured during the COVID-19 pandemic, so research is needed after the pandemic has ended.

Studies on obsession with COVID-19 or PTG are limited to a single hospital, making it difficult to generalize the results. In addition, it is thought that the degree of exposure to COVID-19 patients and the provision of protective equipment at each stage of the pandemic may differ depending on the type of medical institution. Therefore, this study was conducted to investigate the factors affecting post-pandemic obsession with COVID-19 among nurses working in medical institutions of various regions and sizes.

In this study, the mean OCS score was 0.89. In previous studies using the same measurement tool, the mean OCS score ranged from 0.80 to 5.18 depending on the respondents and time of the survey [7,8,18]. Although it is difficult to conclude due to the limited number of studies, it is likely that the proportion of nurses with excessive and recurrent thoughts about COVID-19 decreased as the COVID-19 pandemic gradually moved from a pandemic to a management phase. In this study, 15.1% of the subjects had an obsession with COVID-19, that is, had dysfunctional thoughts, which was similar to the previous study’s 14.6–19.4% [7,8,18]. In a previous study targeting healthcare workers and trainees [19], nurses had the highest score among medical personnel. This reflects the nature of their work that performs infection control in the healthcare setting and cares for patients most closely. Therefore, it is necessary to understand the work of nurses, periodically measure OCS scores, identify the proportion of nurses with excessive COVID-19 thinking, and provide psychological support and job transitions for them.

In this study, the average PTG score was 3.37, which was higher than the average total score of 2.91 [11], 2.41 [20], and 1.76 [12] converted to the average score of previous studies using the same measurement frequency. Most of the previous studies were surveys conducted until 2022, so it is thought to be different from the infection control situation in medical institutions right before the crisis stage in which this survey was conducted was downgraded from the alert stage to the concern stage [21]. An individual’s basic belief system may have changed in the process of caring for a significant number of COVID-19 patients for a long period [22]. In addition, it is thought that the PTG score increased as the repeated difficult situations under the pandemic gave rise to a new perspective through reflection [22].

As a result of analyzing the risk factors of the group with dysfunctional thinking through multivariate logistic regression analysis, age over 31 years, chronic diseases of co-living family, and nursing for confirmed patients within 1 month significant variables. In a previous study investigating the mental problems of healthcare workers [23], most of them included depressive symptoms, anxiety symptoms, and insomnia, and studies on obsession, which represents excessive thinking, were rare, making an accurate comparison difficult. In a previous study of the general population, the OCS score was higher in older people [18]. However, other studies targeting medical personnel did not reach significant conclusions about age [7,19]. Since previous studies were conducted during the COVID-19 pandemic and are thought to be different from this study conducted during the stabilization period, it is necessary to repeatedly study the OCS score according to the demographic characteristics of the subjects.

Although it was difficult to find studies that included the question of nursing for confirmed patients within 1 month, which was significant in the results of this study, there was a previous study that stated that nursing COVID-19 patients was correlated with obsessive thoughts, but no papers supporting this study result were found [7]. Most of the domestic and international studies were qualitative, asking nurses about their experiences while caring for patients, so it was still difficult to find results to support group differences in OCS scores. A study [24] that investigated the mental wellbeing of nurses during the COVID-19 pandemic stated that directly caring for confirmed patients causes fear, but providing clear instructions, information, and protective equipment was a factor that reduced fear. Based on the results of a previous study that OCS is positively correlated with COVID-19 anxiety [16], it can be thought that anxiety about caring for COVID-19 patients causes fear. Therefore, it is important to provide adequate protective gear and updated guidance as appropriate when caring for COVID-19 patients. Furthermore, repeated studies on the relationship between patient care situations and OCS are needed.

In this study, the mean scores for all factors of PTG were higher in the group with dysfunctional thinking, but this was not statistically significant. It was difficult to find articles that studied the relationship between COVID-19 and PTG, and a previous study of the relationship between psychosocial wellbeing and OCS scores in nurses who experienced the COVID-19 pandemic reported that higher OCS scores were associated with poorer psychosocial wellbeing [8], which contradicts these findings. The PTG scores in this study were measured after the end of the pandemic, and it is possible that multiple factors, such as strengthened infection control guidelines in medical institutions and changes in individual beliefs, may have had a complex effect. There is some variation in sample size between the two groups, which may have led to an insufficient number of significant variables [22]. Future studies with larger sample sizes using both OCS and other psychosocial health measures are warranted to explore differences.

This study investigated demographic characteristics, COVID-19-related characteristics, obsession with COVID-19, and PTG of nurses working in various medical institutions nationwide. The limitation of this study is that it did not identify the influence of institutional characteristics and PTG on obsession with COVID-19. However, by examining obsession with COVID-19 during the routine phase of the pandemic, this study provides foundational data that can be used as a basis for understanding the long-term effect of the pandemic and the effectiveness of related policies.