Since the outbreak of 2019 novel coronavirus (COVID-19) in Wuhan, Hubei province, China in late December 2019 (1–5), COVID-19 cases are still being continuously confirmed all over the world (6). This disease was transmitting so fast that the health-care system had been facing a sudden crisis. Moreover, the mortality rate was considerable in critically ill patients, as high as 61·5% (7). It is no doubt a huge challenge for medical staff never met before.

Reports showed that many health-care workers had been infected by COVID-19, and some of them had died (8–11). The mental stress of the health-care workers increased significantly when they cared for a large number of anxious COVID-19 patients with high-intensity work (12, 13). Lai (14) reported that health-care workers experiencing psychological burden, directly engaged in the diagnosis, treatment, and care for patients with COVID-19. Therefore, the medical staff for COVID-19 patients wore thick personal protective equipment (PPE) to protect themselves not being infected in the early outbreak in China, including three layers of medical hats, two layers of medical masks (N95 and surgical mask), eye protection (goggles or face screens), two layers of waterproof isolation clothing (a long fluid-impermeable gown and an operating coat), two layers of gloves, and two layers of shoe covers (Figure 1). This combination of PPE may cause increased work of breathing, reduced field of vision, muffled speech, difficulty hearing, and heat stress (15). Also, the medical staff who care for patients infected with COVID-19 are at a high risk of pressure injuries that caused by protective equipment in the prevention process (16). A growing concern regarding skin problems has been identified among healthcare workers during the COVID-19 pandemic (17–19), and the PPE-related skin injury can be serious (20). Daye (21) reported that skin problems were found to be 90.2%, the most common were dryness, itching, cracking, burning, flaking, peeling and lichenification. Severity of skin reaction was found to be significantly related to “hours per day of PPE use,” “consecutive days of PPE use,” and “female sex” (22). In the study by Proietti et al., prolonged use of PPE was a significant risk factor for developing skin related adverse events considering all the PPE considered (23). These occupational dermatoses caused by PPE in the ongoing COVID-19 pandemic are emerging occupational health challenges (24).

Therefore, the frontline medical staff faced great work stress and physical challenges during COVID-19 epidemic in the early outbreak. However, their physical discomforts and the feeling of the work intensity were not detailed described in previous studies. The survey was to comprehensively investigate their physical discomforts, the feeling of the work intensity and the related risk factors. When people face similar outbreaks in the future, these precious data may be learned from by the medical workers.

As the continue increases of the confirmed COVID-19 cases worldwide, health-care systems globally could be operating at more than maximum capacity then and the health-care workers were every country’s most valuable resource (25). The medical staff were under great pressure in the early outbreak. In a district general hospital in south London, 128 (39%) of doctors experienced at least one sickness episode (26). However, there is no detailed description of the physical discomforts of the medical staff for COVID-19 during the early outbreak. Facing the unknown virus, COVID-19 medical staff kept wearing thick PPE during their work in the early stage of the outbreak. The survey showed that COVID-19 medical staff had different physical discomforts and they felt high work intensity.

The incidence of the physical discomforts related to PPE (such as dyspnea, pain, chest distress,etc.) was high in our survey and these effects were really inevitable. They are not caused by individual weakness; they are normal and expected reactions that any person will have when exposed to an unusual environment (15). Sahebi A also found that the prevalence of PPE-associated headache was relatively high, and the prevalence after and before the use of PPE was 48.27 and 30.47%, respectively (27). Adverse effects of PPE were associated with longer shift durations (28). In our study, PPE was worn for 4–6 h in 89.1% of the participants. Since the mean peak time of these physical discomforts was 3.5 h in our study, it indicates that the ideal working hours for the COVID-19 medical staff should be around 4 h every time. Also, 70.9% of them expected the effective working hours/per time to be 4 h. If PPE and human resources became sufficient, medical staff should take reasonable shifts to ensure physical health, otherwise the efficiency and quality of their work might decrease. However, due to the limitations of PPE or human resources, some of them had to work continuously for more than 6 h, which might easily cause distractions from their work. If working hours/per time cannot be shorten, some other work strategies should be applied.

Most of the medical staffs involved in the study worked for severe and critically ill patients, 162 medical staffs (31.5%) and 234 medical staffs (45.4%), respectively. When wearing thick isolate clothes, it is more difficult to perform procedures for COVID-19 patients, particularly for critically ill COVID-19 cases requiring complicated invasive procedures, such as tracheal intubation and arterial puncture/venipuncture. High frequency of performing these procedures would significantly increase the workload of the medical staffs and shorten their peak time of physical discomforts. Some measures might be beneficial for performing centralized treatments, and saving human resources, such as setting up a specialized procedure team, classifying patients being according to their severity. More work is needed to summarize and share the reasonable COVID-19 patient management.

The COVID-19 medical staff may experience considerable psychological distress due to providing direct patient care, vicarious trauma, quarantine, or self isolation (29, 30). Sleep disorders, in particular insomnia, have been commonly reported in frontline medical workers (31, 32). A meta-analysis, which included 98,533 medical staff from 71 studies, found the prevalence of insomnia among Chinese medical staff during the COVID-19 outbreak was generally high, especially for first-line workers (33). Our result showed that more than half of the medical staffs suffered from sleep disorders, and the effective daily sleep time was an independent influential factor for work intensity. These workers who had shorter effective daily sleep time during the COVID-19 work period felt higher work intensity. The medical staff were under high pressure even in the break time, which might be a major reason that lead to sleep disorder. The results indicated that only about 25% of medical staffs were not anxious about being infected by COVID-19, whereas 10% of them were highly worried about being infected by COVID-19 even during breaks. Moreover, anxiety levels of medical staffs at break time was an independent related factor for work intensity, and medical staffs with a VAS score of ≥six at break time felt a significantly higher work intensity than did those with a VAS score of zero. During the early phase of the pandemic in the Philippines, one-fourth of respondents reported moderate-to-severe anxiety and one-sixth reported moderate-to-severe depression and psychological impact (34). Besides, the workload of taking care of COVID-19 patients is very overwhelming, which challenges physical and mental limitations of medical staff all the time. Many other factors, such as change of living habit, food and environment in the isolation regions, would affect their effective sleep time, which in turn reduce the quality and productivity of their work. The risk of psychological effects from the COVID-19 pandemic is significant and manifests as stress, anxiety, depression, sleeplessness, and, in some cases, suicide (35). Therefore, it is of great importance to monitor the mental and psychological state of COVID-19 medical staffs, and provide professional psychological interventions as needed.

The psychological issues may induce healthcare workers experienced burnout during the pandemic. Ibar C found that 12% of the studied population showed burnout (52% doctors and residents, 19% nurses, 19% administrative personnel) and healthcare workers are subjected to increased levels of stress and burnout (36). Other than poor sleep, long working hours was a risk factor regarding an increase in personal burnout, work-related burnout levels and depression among health care professionals (37). The medical staff in China have been working for COVID-19 treatments in isolated areas for about 3 years. The mean continuous working days of medical staffs was 26.3 days during our survey time. However, health-care workers, unlike ventilators or wards, cannot run at 100% occupancy for long periods (25). Training workers about appropriate coping styles to adopt may be essential to enact prevention strategies to reduce burnout incidence in workers (38). Also, it is crucial to design an appropriate work schedule for medical staff, otherwise their health would be under risk and the work quality might also decrease.

Furthermore, Vancappel (39) reported that post-traumatic symptoms were also highly prevalent among French healthcare workers at the beginning of the COVID-19 crisis and they found a significant effect of the level of exposure to COVID-19 on affective symptoms. In the study by Oliver TL, the results implied that the COVID-19 pandemic had immediate effects on the eating patterns, weight changes, PA, and psychological factors of healthcare workers (40). In a large-scale survey during the COVID-19 pandemic, the results indicated that nurses who identified as women, working in ICUs, COVID-19 designated hospitals, and departments involved with treating COVID-19 patients had higher scores in mental health outcomes (41). Leaders within the hospital should investigate the working conditions and personal habits of all medical staff regularly and systematically during the COVID-19 pandemic and take any necessary preventive measures, such as improving resilience for nursing staff, in order to best care for their employees (37).

The frontline medical staff for COVID-19 felt different physical discomforts when they wear thick isolation clothes at work in the early outbreak and they felt high work intensity. These precious data will help optimize the work management strategy to ensure the physical and mental health of medical staff in the face of similar outbreaks in future.

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

This study was deemed non-human-subjects research by the institutional Review Board (IRB) of the Harbin Medical University. As a result, ethical approval and written informed consent to participate in this study were not required for the study.

LJ: Data curation, Formal analysis, Writing – original draft, Writing – review & editing. MY: Data curation, Writing – review & editing. HoW: Data curation, Writing – review & editing. HuW: Data curation, Formal analysis, Writing – review & editing.