Risks of occupational illnesses among health workers providing care to patients with COVID-19: an integrative review

Objective: to analyze evidence concerning the risks of occupational illnesses to which health workers providing care to patients infected with COVID-19 are exposed. Method: integrative literature review conducted in the following online databases: Medical Literature Analysis and Retrieval System Online (MEDLINE/PubMed), Web of Science (WoS), Excerpta Medica Data-Base (EMBASE), Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Scopus (Elsevier). Original articles published between November 2019 and June 2020, regardless of the language written, were included. A descriptive analysis according to two categories is presented. Results: the sample is composed of 19 scientific papers. Most were cross-sectional studies with an evidence level 2C (n=17, 90%) written in English (n=16, 84%). The primary thematic axes were risk of contamination and risk of psycho-emotional illness arising from the delivery of care to patients infected with COVID-19. Conclusion: the review presents the potential effects of providing care to patients with COVID-19 on the health of workers. It also reveals the importance of interventions focused on the most prevalent occupational risks during the pandemic. The studies’ level of evidence suggests a need for studies with more robust designs.


Introduction
In 2020, a pandemic caused by the novel coronavirus (COVID-19) devastated the world, causing thousands of deaths. COVID-19 originated in China at the end of 2019 and rapidly spread worldwide. The disease may cause a pandemic respiratory syndrome called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), requiring, in some cases, critical or intensive care arising from more complex and severe conditions (1) .
The first cases in Brazil were recorded in February 2020, and the number of infected people and deaths due to COVID-19 has only increased. Brazil currently ranks second with the highest number of cases, lethality of 2.9% and mortality rate of 76.7%, only behind the United States; 161,106 deaths have been counted so far (2) .
Many countries reported a collapse of their health systems at a certain point of the pandemic and experienced a lack of personnel and material and physical resources to care for all the individuals infected with COVID-19 (3) .
Additionally, the virus' high transmissibility and spreading rate, higher than that estimated at the beginning of the pandemic, increased the risk of occupational exposure and illness, especially among health workers assisting infected patients (4) .

Becoming immune after being infected with COVID-19
is not certain, and vaccines are still undergoing clinical tests. While immunological barriers are not consolidated and ensured by science, health workers, especially those in direct contact with patients infected with COVID- 19, can only resource to physical barriers such as personal protective equipment (PPEs), social distancing, and hand and environment sanitation to protect from and minimize the risk of contagion (5)(6) .
The different working conditions of the various productive sectors, the health history of employees, conflict of roles, problems faced in interpersonal relationships, and biological and/or psychosocial risks arising from the professional activity are maximized by long working hours, lack of PPEs, and potential physical, emotional or mental distress imposed to health workers during the pandemic. As reported by a study conducted in Spain (4) , health managers should consider these factors a sign to intensify strategies intended to promote occupational health and prevent diseases.
It is crucial to preserve workers' health to minimize the dissemination of COVID-19 and manage the effects of contamination, which reflect on hospital facilities and primary health care services (7)(8) . Therefore, occupational health strategies are essential to provide protective barriers and provide support and integral care, including psycho-emotional care. The establishment of effective actions requires identifying the occupational risks to which health workers are exposed (9) .
Thus, this investigation is based on the importance of producing and aggregating knowledge by searching the scientific literature to ground health promotion activities, minimizing the risk of occupational illnesses among health workers exposed to patients with confirmed or suspected COVID-19 infection. This study's objective was to analyze evidence concerning occupational risks to which health workers providing care to patients with COVID-19 are exposed.

Method
This literature Integrative Review (IR) was conducted through six distinct stages: 1) establishment of the guiding question; 2) search and selection of primary studies; 3) extraction data from primary studies; 4) critical assessment of the primary studies; 5) synthesis of results; and 6) presentation of results (10) .
The guiding question was established according to the PICO strategy (P-population, I-Intervention, C-comparison, and O-outcome) (11) to increase the probability of finding evidence in secondary sources that meet the assumption of Evidence-Based Practice. Thus, the following guiding question was established: "What are the occupational risks to which health workers providing care to patients infected with COVID-19 are exposed?" The search strategy used to meet the integrative review's objectives includes controlled terms combined with boolean operators adapted to the specificities of each database. See details in Figure 1. The Oxford Centre for Evidence-based Medicine (12) classification was used to analyze the level of evidence: 1A -systematic review (with homogeneity) of randomized

Results
A total of 1,656 scientific papers were identified, and 1,617 were eliminated after applying inclusion and exclusion criteria. A total of 97 were duplicated, while the titles and abstracts of 1,520 papers were not pertinent due to the following reasons: were not an article, not research, did not address the theme, or did not answer the guiding question.
After this stage, the full texts of 39 papers remained.
The researchers excluded 15 of these because they did not answer the guiding question, while a consensus was obtained to exclude another five papers. Finally, 19 papers remained, as shown in the flowchart presented in Figure 2.     (27) Observational crosssectional study/534 participants/China.
To investigate the impact of coping strategies adopted by the medical staff working in the front line in the province of Hunan, adjacent to the Hubei province, during the COVID-19 ¶ outbreak between January and March 2020.
The nursing staff experienced more significant nervousness and anxiety than the other groups ( ¶ ¶ p=0.02  of health providers exposed to  . In this sense, a study conducted in China (15) highlights that the physicians and nurses directly working with patients infected with COVID-19 who did not properly wash their hands after having contact with these patients were at the greatest risk of becoming infected with COVID-19.
Those facing longer working hours, especially in highrisk wards, providing care to infected patients in critical conditions, were also at a greater risk of contamination.

Discussion
The findings are presented according to two thematic The reason is that patients in these conditions require greater assistance, which results in workers being more exposed to aerosol-generating procedures (15) .

Effectiveness linked to the appropriate use of PPEs
and adherence to rigorous sanitation measures in a tertiary hospital in Germany is reported to protect health providers against the spreading of COVID-19 from patients with a confirmed or suspected diagnosis (16) . Sensitization regarding the risk of COVID-19 infection is crucial, even in wards not admitting infected patients considering contagion intensity and uncertainty regarding signs and symptoms presented by patients.
Authors (16)  There was difficulty in identifying the route of transmission of three workers (60%) who suspected of having being infected after being exposed to infected patients who were not protected; the route of infection was unknown in two cases (40%) (16) . Adherence to sanitary standards and social distancing is crucial, considering that asymptomatic infections or contamination from unknown sources remain routes of transmission and contamination in hospitals and social settings.
The authors (17)  These results alert to the need to urgently implement adequate protection and support strategies for health workers during the pandemic. However, as stated by the authors (17) , these findings are limited and cannot be generalized as they originate from a cross-sectional study in which an intentional sample composed of workers providing care to critical patients with varied diagnoses was used. Nonetheless, these results reinforce the importance of health facilities performing internal assessments to prevent and minimize the contamination of health workers exposed to diverse pathogens.
On the one hand, the use of PPEs is intended to protect health workers from the COVID-19 infection; on the other hand, this equipment's prolonged use may cause discomfort and worse previous pathological conditions (18) . Additionally, 158 (100%) health workers report increased use of PPEs since the COVID-19 outbreak in Singapore (18) . On average, the interviewees wore an N95 mask for 18.3 days, 5.9 hours a day on average; 96.8% of the interviewees wore protective goggles. The authors (18) verified that 87.5% of the participants reported a feeling of pressure or heaviness on the affected sites, characterized by some as a throbbing (n=15, 11.7%) or pulling pain (0.8%). The study's participants reporting pre-existing primary headaches and those working in the emergency room were more likely to develop headaches associated with the prolonged use of PPEs.
Based on the previous discussion (14,18) , it is essential to pay attention to the risk of health workers acquiring illnesses other than the COVID-19 infection and protect these workers' integral physiological and psycho-emotional health. Hence, the appropriate use of PPEs should be assessed and whenever possible, rotate health workers providing care to patients with a confirmed or suspected COVID-19 diagnosis to decrease the time workers are exposed to the disease and minimize the prolonged use of PPEs.

Risk of psycho-emotional illness among health workers providing care to patients infected with COVID-19
The mental health of medical and nursing teams has been considerably challenged during the COVID-19 pandemic. Health workers gradually presented psychological distress during the pandemic; fear and anxiety preceded depression, psychophysiological changes, and post-traumatic stress. Being isolated, working in sites with a high risk of contamination, and having contact with infected patients are common causes of trauma, negatively impacting workers' mental health and triggering psycho-emotional illnesses (21) .  (19) .
The analysis shows an interaction between anxiety levels presented by the health staff during the different demands of patients with COVID-19, resulting in increased stress levels and decreased self-efficacy and sleep quality.
Additionally, social support as a protective mechanism during the pandemic appears relevant (23) .  (27) were the most effective in decreasing stress.
Regarding the rates of burnout syndrome among workers from the multi-professional team at the cancer hospital of Hubei, China, a significantly lower frequency of the burnout syndrome was found (25)  The results present the primary occupational risks described during the pandemic of the novel coronavirus.
These are biological and psychosocial risks that are intricate in a care delivery historical past arising from direct care delivery, which obviously became more acute within the context of providing care during the pandemic.
The studies first showed the occupational risk of In this sense, studies developed during the current pandemic show an urgent need to assess the risks to which health workers are exposed during occupational activities.
Illnesses go beyond the physical and physiological spheres, negatively impacting the individuals' psycho-emotional conditions, compromising their wellbeing, quality of life, and work performance.
Similarly, processes within the work environment and care delivery context to deal with this public health problem include the hospital setting's management, highlighting the importance of health managers to implement strategies to manage occupational risks in health services.
Therefore, investment is needed to prepare, assist, and provide mental health devices to protect and care for future multidisciplinary teams who may be surprised with the need to be on the front lines to combat the outbreak of infectious diseases.
At the same time, it is vital to ensure workers are qualified, that there are sufficient and quality PPEs to protect the health and wellbeing of workers, sufficient personnel to enable multidisciplinary teams to take turns between work periods and breaks, to minimize impacts on the health of workers arising from excessive working hours.
These results suggest a need to implement structured, evidence-based interventions addressing