Incidence of COVID-19 in Health Care Personnel in a Tertiary Hospital in Iran

Document Type : Short communication

Authors

1 Department of Internal Medicine, Sina Hospital, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran

2 Department of Pulmonary Diseases, Sina Hospital, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran

3 Students’ Scientific Research Center (SSRC), Tehran University of Medical Sciences, Tehran, Iran

4 Research Development Center, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran

5 Research Center For Clinical Virology, Tehran University of Medical Sciences, Tehrn, Iran

Abstract

Background: Since the initiation of the new coronavirus (COVID-19) in February 2020 in Wuhan, the Health Care System (HCS) has tolerated a lot of morbidities and mortalities all around the world. While the COVID -19 is spreading out the whole world, HCS carries almost all the burden as the first line. However, countries like Iran suffer from a lack of infected Health Care Workers (HCW) population data and statistics, especially the major hospitals for COVID-19 referrals. 
Methods: In this single-center cross sectional study, we studied the healthcare personnel infected by COVID-19, from February 2020 to August 2020, in a major tertiary hospital of Tehran, Iran.
Results: Of total 1595 HCW working in Sina hospital, 389 (24%) with the mean age of 35.43 ± 8.2 years were infected by COVID-19, almost one fourth. 238 (61.2%) were women, though 92.5% of the population used Personal Protective Equipment (PPE). 140 (36%) of them were personnel of the wards assigned to the COVID-19, Personnel went on sick leave for 7.76 ± 4.64 days. 51(13.1%)  personnel had an exacerbation of symptoms, and only one of the personnel experienced COVID-19 almost twice in four months.
Conclusion: COVID-19 infection risk is considered to be very low for HCWs in case suitable PPE and social distancing are regarded. In our study, more than 92% of the infected personnel utilized PPE, which indicates that they might have failed to use PPE properly or might not have taken hand-hygienic precautions well. It is necessary to limit working hours and prevent excessive workload so that the staff could adhere more to hygienic precautions in hospitals or in society. 

Keywords


Abstract
Background: Since the initiation of the new coronavirus (COVID-19) in February 2020 in Wuhan, the Health Care System (HCS) has tolerated a lot of morbidities and mortalities all around the world. While the COVID -19 is spreading out the whole world, HCS carries almost all the burden as the first line. However, countries like Iran suffer from a lack of infected Health Care Workers (HCW) population data and statistics, especially the major hospitals for COVID-19 referrals. 
Methods: In this single-center cross sectional study, we studied the healthcare personnel infected by COVID-19, from February 2020 to August 2020, in a major tertiary hospital of Tehran, Iran.
Results: Of total 1595 HCW working in Sina hospital, 389 (24%) with the mean age of 35.43 ± 8.2 years were infected by COVID-19, almost one fourth. 238 (61.2%) were women, though 92.5% of the population used Personal Protective Equipment (PPE). 140 (36%) of them were personnel of the wards assigned to the COVID-19, Personnel went on sick leave for 7.76 ± 4.64 days. 51(13.1%)  personnel had an exacerbation of symptoms, and only one of the personnel experienced COVID-19 almost twice in four months.
Conclusion: COVID-19 infection risk is considered to be very low for HCWs in case suitable PPE and social distancing are regarded. In our study, more than 92% of the infected personnel utilized PPE, which indicates that they might have failed to use PPE properly or might not have taken hand-hygienic precautions well. It is necessary to limit working hours and prevent excessive workload so that the staff could adhere more to hygienic precautions in hospitals or in society. 
Keywords: COVID-19, Healthcare personnel, Infection

Introduction
Since the beginning of the new coronavirus pneumonia disease 2019 (COVID-19) outbreak on 31th of December 2019 from Wuhan in China, people and especially the Health Care System (HCS) has tolerated a lot of morbidities and mortalities (1-3). According to the latest World Health Organization (WHO) situation reports in late August 2020 considering the COVID-19 burden, approximately 21 million officially reported cases of COVID-19 were detected all around the world with more than 750000 deaths (4). All of these statistics demonstrate how COVID-19 inspired the quality of life. While the COVID-19 is spreading out the whole world, HCS carries almost all the burden as the first line. Besides, HCS and the frontline Health Care Workers (HCW) suffer a lot of human and financial losses. Primary situation data just from the origin of the outbreak, Wuhan, on the 25th of February 2020 reported 3387 infected HWCs along with at least 18 deaths (5,6). Unfortunately, a group of HCWs consisting of Dr. Chaolin Huang and his colleagues, who had introduced the COVID-19 clinical manifestations, passed away due to a new coronavirus infection (7). On March 15, 2020, Italy recorded 2026 confirmed COVID-19 cases of HCWs (8). Recent valuable shreds of evidence express COVID-19 virus transmitted via droplets, small 5-10 μm particles indeed, in direct person to person contacts (9,10). Although it is recommended to have social distancing, wearing the face mask, and staying home to reduce the risk of infection (11), HCWs should allocate more hours to HCS duties (12). Often this strange new coronavirus disease does not have typical COVID-19 manifestation, thus people with insufficient Personal Protective Equipment (PPE) can easily transmit it to others (12,13). Therefore, not only do HCWs contact more COVID-19 viral loads, but also lack of PPE puts them in danger of infection (14). The first confirmed COVID-19 case in Iran was reported on 19 February 2020 in Qum province (15). Now Iran is known as one of the top 20 countries in prevalence and incidence of COVID-19 with 340,070 confirmed cases and 19,492 total deaths based on the latest WHO report on the 16th of August 2020 (4). Also, 8.41% mortalities among HCWs were reported as of March 28, 2020 in Iranian population (16). Many infected cases in Iran are front-line personnel, but there was not enough scientific evidence to demonstrate the estimated cases so far, especially in major tertiary hospitals in Iran. In this study, we collected information from HCWs infected with COVID-19 in one of the most referral hospitals in Iran along with the data regarding new coronavirus clinical features or positive tests. The current study can be important and informative due to the lack of information among HCWs population as the front line of COVID-19 disease in Iran, and it aims at contributing to future studies to have a better insight about major hospitals and their bias. 

Materials and Methods
In this single-center cross-sectional study based in Sina Hospital as a major tertiary hospital in Tehran, Iran, from February 2020 to August 2020, 1595 HCWs with COVID-19 were considered as the study population. We evaluated HCWs with the positive test via real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) performed by oropharyngeal swab. Besides, according to the latest World Health Organization’s interim guidance and Iranian national committee of COVID-19, we included patients with a history of COVID-19 manifestations along with Ground-Glass Opacity (GGO) alone or GGO accompanied with consolidation in chest Computed Tomography (CT) (17,18). Also, patients with highly suspicious clinical features for COVID-19 were added up. The algorithm of patient care for individuals presenting with respiratory symptoms to Sina Hospital has already been published (19).
Data were collected via a well-designed form that includes clinical features, exposures with family prior to the COVID-19 confirmation, history of exposure with known cases of COVID-19 in their work sections, signs and symptoms during the disease, and underlying health conditions among HCWs with COVID-19. Demographic characteristics, exposures, symptoms, and underlying health conditions among HCWs were recorded. Patients were classified by their hospital position and the department and sections they work in. PPE using was considered. Symptoms (such as fever, cough, dyspnea, myalgia, anorexia, and sore throat, all as the main manifestations) were considered based on the latest COVID-19 shreds of reports (20,21). 
This study was approved by the Ethics Committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1399.231)

Statistical analyses
We considered the mean ± standard deviation for continuous variables’ descriptive data, and categorical variables were presented as numbers (percentage). All statistical analyses were performed using the SPSS version 23.0 software (IBM, Armonk, New York).

Results     
Through this study, we considered 389 HCWs, classified by gender, confirmed for COVID-19 by PCR tests, radiographic (CT-scan) pattern or based on clinical presentation.
Among 1595 staff members working at Sina hospital, almost one fourth of the service personnel in different departments of this hospital have experienced the symptoms of COVID-19 disease.
In this study, of 389 HCWs (24.38%) as patients with the mean age of 35.43 ± 8.2 (20-60) years, 238 (61.2%) were women. Based on the ward type, 140 (36%) personnel of the wards assigned to the COVID-19 were infected, and among them, 51 patients (13.1%) were personnel of COVID-19 wards, 43 (11.1%) were personnel of COVID-19 ICU, and 46 (11.8%) were COVID-19 emergency department personnel. Information on other (non-frontline) sections is given in table 1. On average, the personnel infected with COVID-19 went on sick leave for 7.76 ± 4.64 days. 51 (13.1%) personnel had an exacerbation of symptoms, and only one of the personnel experienced COVID-19 almost twice in four months. Only seven individuals were hospitalized, all of whom were discharged in good health. We followed all these seven people and all of them had a complete recovery. There was no death in total.
As shown in table 1, PCR was performed in 258 patients (66.3%) of whom 133 (51.6%) were positive. Chest CT-scan was performed for 208 patients, of whom 55 (26.4%) had pulmonary involvement in favor of COVID-19. In chest CT-scans; 94.5% of patients had GGO alone, and 5.5% had GGO accompanied with consolidation. Lung involvement was mostly reported bilaterally (53.7%).
The patients’ body temperature at baseline was 37.01± 0.7 °C with a maximum of 40 °C. The mean blood oxygen level was 96.7 ± 1.8 (85-99). Among the initial symptoms, myalgia with 225 patients (57.8%), cough with 213 patients (54.8%), and fever with 197 patients (50.6%) were the most common complaints. Nine patients (2.3%) had more than one underlying disease. Among the underlying diseases, cardiovascular disease with 3.1% and diabetes with 2.6% were the most common ones. Sixty-four patients (16.5%) had a history of COVID-19 infection in at least one of their family members prior to becoming infected, and 39 (10%) had it after they became infected. Besides, 290 (74.6%) patients had a history of taking care of infected patients. Of the 389 individuals with probable COVID-19 infection, 360 (92.5%) utilized PPE. The most likely drug prescribed for patients was chloroquine and Naproxen. All the suggestive treatments had been considered based on experts’ orders and recent shreds of reports on COVID-19 management (Table 1).

 

Table 1. Demographics and baseline characteristics of patients infected with COVID-19

Variable

Percentage

Total number

Gender

Woman

61.2

238

Man

38.8

151

PCR test result

Test done

66.3

258

Positive

51.6

133

Negative

48.8

125

Chest CT-scan

Chest-CT¶       scan  

done

53.5

208

Chest-CT         scan

deficits

26.4

55

Ground            Glass 

Opacity

94.5

52

Ground            Glass   

Opacity            with

consolidation

5.5

3

Symptoms

Fever

50.6

197

Chilling

33.2

129

Shortness of breath

29.8

116

Coughing

54.8

213

Myalgia

58.1

226

Dry mouth

19

74

Anorexia

30.3

118

Weakness/tiredness

158

40.6

Sore throat

34.7

135

Headache

40.1

156

Olfactory change

17

66

Taste change

17

66

Diarrhea

26.2

102

Nausea

19.8

77

Vomiting

27

6.9

Chest discomfort

 

 

                   17

                66

Past medical history

Diabetes

2.6

10

Cardiovascular disease

3.1

12

Hypertension

1.5

6

Respiratory disease

2.1

8

Immunodeficiency

1.3

5

Others

 

 

0.6

2

Drugs prescribed for Covid-19

Oseltamivir

29

7.5

Chloroquine

168

43.2

Azithromycin

32

8.2

Levofloxacin

4

1

Lopinavir/Ritonavir

9

2.3

Naproxen

70

18

Dexamethasone

12

3.1

Acetaminophen

 

 

35

9

Job categories

Doctors

54

13.9

Nurse and nurse assistants

194

49.9

Hospital services workers

22

5.7

Official clerks

32

8.2

Paramedical staff

27

6.9

Operation room workers

33

8.5

Secretaries

 

 

27

6.9

Sections

Operation room

53

13.6

COVID-19 ward

51

13.1

COVID-19 ICU§

43

11.1

COVID-19 Emergency room

 

46

11.8

Non-COVID-19 wards

68

17.5

Non-COVID-19 ICU

30

7.7

Non-COVID-19 Emergency room

 

8

2.1

Laboratory

14

3.6

Radiology

3

0.8

Clinic

8

2.1

Office

 

26

6.7

Personnel protective equipment usage

Surgery masks

88.4

344

N95 Masks

42.2

164

Medical Protective Clothing

40.1

156

Protective Glasses

18.3

71

Face Shield

22.6

88

Gloves

70.7

275

-  ¶ chest computed tomography; § Intensive care unit

 

Discussion
We reported 389 patients who were HCWs in Iran from March to July 2020. By performing all diagnosing evidences, we demonstrated 24.38% infection proportion among all HCWs in Sina Hospital vs. another study in the United Kingdom which was performed by PCR swab tests with only 5% (22), or in Qatar as one of the Middle East regions like Iran, 10.6% of HCWs were reported as COVID-19 confirmed patients (23). However, in the United States of America and Italy, almost 20% of HCWs were diagnosed as COVID-19 infected patients. Moreover, China reported that 3–4% of HCWs were infected with COVID-19 (24). However, in a study based in the southern Italy, Naples, it was revealed that 3.4% of HCWs were diagnosed with COVID-19 after performing RT-PCR and serology tests (25).
HCWs are the front line fighters against this new outbreak. More than half of our study patients presented with at least one symptom among cough, fever, and myalgia, which indicates that disease presentation is similar to the population other than health workers (12,13).
According to recent studies, COVID-19 transmission is so fast by small droplets that can easily infect many people in a swift time as we knew asymptomatic COVID‐19 carriers transmitted the infection to the community by a person-to-person contact (26,27). Droplets that are expelled through coughing, sneezing, and even breathing in COVID-19 infected people can be the primitive way of COVID-19 transmission (28). There would be a lot of asymptomatic infected people that easily live and breathe beside others and spread out the disease. This may claim the fast growth in COVID-19 pandemic patients (29). Although there are several recommended ways to diagnose COVID -19, such as CT-scan, RT-PCR, and typical clinical manifestations of this virus, patients are considered by a compound of these results. RT-PCR is more common these days due to easy access and performing by a few swabs; however, recent studies have shown that CT-scan has more than 90% sensitivity vs. RT-PCR with 70% to 80%. Hence, by performing RT-PCR, some patients would be missed as a false negative result (30,31). In our study, due to the lack of a sufficient number of diagnostic kits in the early weeks of the COVID-19 pandemic, PCR test was performed with 258 personnel of which 51% were positive that could associated with test sensitivity and false negative tests.
HCWs’ job circumstances such as long hours shifts, direct contact with infected patients, and various PPE access reveal that they are at high risk of infection (32). HCW exposures are significantly greater than a normal person such as direct and indirect contacts with atypical or asymptomatic patients for COVID-19, family, friends, colleagues, and communities of active transmission (33). In this study, nurses and their assistants had the highest number of COVID-19 infection (49.9% of total). The results of the Qatar study are in line with this result (33.2% of all). Nurses spend more time with patients and the virus-infected settings. Perhaps this is why nurses are more likely to become infected. (22). Based on the recommendation for HCWs caring like using suitable PPEs and social distancing, COVID-19 infection risk is considered to be very low (34). A considerable prospective observational study in the United Kingdom and the United states of America has shown that the risk of Coronavirus infection was increased among HCWs with inadequate PPE or reused PPE indeed (35). In this study, more than 92% of the infected personnel used PPE such as medical or N95 masks, guns and gloves, shields, or glasses; their infection indicates that either they failed to use properly or they did not take hand-hygienic precautions at hospital, at home or in society well. HCWs should be ensured about the proper PPEs and facilities while they are at work to improve community hygiene against the outbreak. Reuse of PPEs, unavailability or improper use of equipment may significantly increase the risk of transmission. One of the causes of disease transmission among health workers can be not using PPEs while resting or eating and also not meeting social distancing during the rest time. This transmission may also stem from contaminated surfaces at restrooms, therefore daily environmental cleaning and disinfection is recommended. It is necessary to limit working hours and prevent excessive workload so that the staff could adhere more to hygienic precautions in the restrooms. Proper ventilation in the restroom is another important point.
Also, we can mention that positive history of cardiovascular diseases and diabetes mellitus may play a key role for more mortality and morbidities. Moreover, they are in a higher risk of being infected. Among all the HCWs in different parts of hospital, personnel in COVID-19 wards are in danger of being infected and higher risk of physical damages than the other parts. We also suggest that according to the most prevalent manifestations in this study, each HCW with history of myalgia or cough or fever as initial symptoms even in mild ones refer to complete workups regarding COVID-19.

Acknowledgements 
We acknowledge all the hardworking health-care workers involved in the diagnosis and treatment of patients in Sina Hospital, doing their best in the time of the pandemic. We are indebted to the Research Development Center of Sina Hospital for their help and support. This study was approved by the Ethics Committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1399.231). 

Conflict of Interest 
The authors declare that there is no conflict of interest

Funding
This study has been supported by the Tehran University of Medical Sciences [Grant number: 99-1-101-47546]. The funding source had no role in the study design, data collection, data analysis, data interpretation, writing of the manuscript, or decision of submission.

Ethical approval
This study was approved by the Ethics Committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1399.231).

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