Nowadays, the Coronavirus Disease 2019 (COVID-19) has become a global public health problem. The World Health Organization announced the disease as a pandemic on March 11, 2020. In Iran, the first case of COVID was reported in early March 2019, and until October 5, 2021, more than 5.97 M Iranian individuals have been infected with the virus, and 127K deaths.

Healthcare workers (HCWs) are the frontline fighter of the pandemic. According to nurses' vital role in taking care of patients during epidemics in terms of prevention and disease control, their health is paramount to managing and overcoming infectious diseases (1). However, due to possible exposure, they are susceptible to COVID-19 infection, making them a reservoir of the virus transmission to others (2, 3). Like other healthcare workers, tremendous pressure and stress related to the workplace in their daily job is seen among the nursing staff, especially due to a shortage of personal protective equipment, inadequate support, and a high risk of infection (4–7). It is evident and consistent with the prior outbreaks that HCWs are at higher risk of developing mental health problems (8). Altered mental states among nursing professionals can impact their job satisfaction, which reduces their professional capacity (9). In addition, such a situation negatively affects their attitudes toward patients, which may appear by the changes in nursing treatment and caring behaviors (10, 11).

Accumulated energy and resources from interpersonal relationships are called social capital; it is beneficial to reduce anxiety and pressure and helps in mental stability through increasing social support and enhancing coping capacity (12–15). Thus, more investment in social capital is one of the factors associated with more social support, resulting in acquiring support from superiors, increasing the sense of belonging, and decreasing the isolation feeling (12, 16). Furthermore, the extent of social relations can be observed in the workplace, whereas the networks and interconnections in performing their duties and responsibilities make up the core of social capital (17, 18). In short, social capital is constructive in the workplace, which improves physical and mental health and increases job satisfaction in nurses (19, 20).

The experience of conflicting ethical values among the HCWs is frequent, which become prevalent during the COVID-19 pandemic. Of these ethical problems and achieving moral goals of nursing care services, patients' optimal well-being is prioritized. In order to solve ethical conflicts and fulfill moral quests related to their profession, moral courage is yet to achieve (21). The ethical problems and moral distress should not be continued forever (22–24) as this can cause adverse consequences such as distancing the nurse from nursing care and even leaving the profession for good (25, 26). In addition, irritability, burnout, sleep, and even sleep disorders can result from moral distress (27), which negatively affects their happiness and patient care quality.

Happiness is one of the indicators that reflects how any professional staff is enjoying the job (2). In the occupational nursing condition, altruism, self-confidence, obligation, creativity, kindness, and energy are required, all of which are related to happiness (28–31). Happy nurses enjoy their professional roles and responsibilities, as happiness makes them creative to perform their work and positively affects their organizational performance (32), which significantly impacts nursing services and patient satisfaction. A specific characteristic of social capital is that, in contrast to other factors, the resource does not lie in the social actors themselves (such as human capital) or the physical means of production (physical capital), but rather in the structure of relationships (33). When members of a collective perceive close relationships, they are more likely to help each other, create effective procedures, and share key information (33).

During the COVID-19 pandemic, there is a lack of studies investigating the level of moral courage and happiness among the HCWs. For instance, a Chinese study reported the changes in happiness over 6 weeks (29). A high level of moral courage (473.33 ± 1.64; range: 102–510) was found among Iranian nurses, where about 65% of the variance in moral courage was explained by age, working experience, employment status, moral sensitivity, and safe nursing care (28). Despite these findings, no studies focused on social capital and its effect on happiness and moral courage during the COVID-19 pandemic. It is hypothesized that workplace social capital might have a positive effect on moral courage and happiness, which has been investigated in this study. In addition, the predictive factors of social capital were also explored in the Iranian nurses working in the COVID-19 wards.

This study is the first approach to investing the relationships between workplace social capital and happiness and moral courage among nurses engaged in treating the COVID-19 patients. It is observed that the workplace social capital influences nurses' happiness and moral courage during the COVID-19 pandemic.

Social capital is being reported to be associated with common socio-demographic factors. For instance, Saberi et al. (43) found that gender had a significant association with trust and security from the dimensions of social capital, where women had lower trust and security scores than men. As consistent with that study, gender was found as the significant predictor of social capital in this study. In addition, evidence suggests that the oldest age people have the highest level of trust, and those with the highest education tend to have more social capital (44). In the present study, people with higher literacy levels were higher in terms of social capital. The independent and joint effects of three dimensions of demographic diversity (gender, race, and age) on organizational social capital in the US federal government were also reported, where there was a negative relationship between age diversity and organizational social capital (45). However, two elements of social capital, including the value of life and feelings of safety and trust, were reported as the consistent predictors of health, life satisfaction, and happiness (46). At the same time, the results of Kim et al.'s study (47) found that among social capital factors, two elements of feelings of trust and safety, neighborhood connections had a significant and positive mediating role in the relationship between sports participation and general happiness. Such a positive association between workplace social capital and happiness has also been proved in European countries, for example, the results of the RodrguezPose's study (48). Furthermore, Hosseinbor and Nabizadeh's study (49) also indicated a positive and significant relationship between social capital with happiness among Iranian medical school faculty members in that country; the present study was also carried out.

Social capital and social support increment were found to have resiliency against COVID-19 with the mediating role of spiritual happiness (50). A person with a high level of happiness is more satisfied with their life because they experience more positive emotions. A high level of workplace social capital explains established extensive contact between nurses and other workplace personnel through long-term interaction and exchange (18). A strong sense of responsibility, identity, and social norms can be obtained by enriching and strengthening network connections among colleagues (51). During social interactions, nurses are likely to encounter emotional behaviors from leaders and colleagues, which helps build up a healthy interpersonal relationships and spreads positive senses (52). Therefore, some factors such as a pleasant workplace atmosphere and good communications with leaders, colleagues, and patients can reduce the work pressure and stress among nurses; they can also attenuate stress impress professional identity (53). Thus, health policy-makers and authorities can make some interventions to develop strategies for improving nurses' happiness and social capital.

Researchers have recently begun to study workplace social courage's role in organizational results; they suggest that courageous behaviors affect positive work behavioral outcomes (54–58). In Mert's study (59), workplace social courage is a facilitator for subjective happiness and life satisfaction. Awareness of the importance of moral courage and its influential factors can help healthcare researchers, educators, clinicians, and leaders demonstrate moral courage, face ethical challenges and ethical environment maintenance (36). It is essential that HCWs value and support their counterparts who dare to resist and converse against unethical behaviors. Professional nursing organizations should countenance nurses to do measures that create and sustain ethical environments; they also should support protections for individuals who combat unethical behaviors in the workplace. All educational and continuing education programs should elevate moral courage; the educational content should include strategies that enable nurses to act bravely when ethical standards are neglected (60).

One of the study's limitations was filling in the questionnaire in the challenging conditions of the nurses, who tried to overcome this by providing the questionnaire online. Another limitation was the self-reported nature of the study, which may have received more positive responses. In order to overcome the limitation, an attempt was made to give the company the necessary assurance that the information was confidential. It should be noted that many factors associated with the dependent variables were not assessed in this study, which can be considered in further studies. Finally, results from cross-sectional data limit the causal interpretation of the associations.

Social capital is an important organizational event, influencing organizational results, including happiness and moral courage among nurses, especially in the clinical settings during the COVID-19 pandemic, as found in this study. Based on the current study's findings, it can be stated that social capital is an essential construct for hospital upgrading. Thus, hospitals need to consider the importance of social capital and organize all policies and practices to promote and enhance social capital. They also should understand the dynamics of social capital and remove all the barriers to social capital development. Furthermore, there should be specialized institutions in universities and official institutions in charge of identifying this concept and planning to promote it, and then monitoring the concept of social capital. Also, the media can do a lot to help make social capital more transparent and recognizable.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by Mazandaran University of Medical Sciences (Approval No. IR.MAZUMS.REC.1399.8950). The patients/participants provided their written informed consent to participate in this study.

MP, HM, NM, and AS conceptualized the study, collected data, and interpreted the results. MM reanalyzed the data, reviewed, and edited the draft extensively. All authors contributed to the writing of the manuscript, approved the final version of the manuscript, and agreed to be accountable for all aspects of the work.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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