Clinical and epidemiological profile of COVID-19 in health professionals: a review of the literature

Abstract

Occupational exposure is an important source of coronavirus transmission among health professionals. The objective of this study is to review the literature on the clinical and epidemiological profile of health professionals infected by COVID-19. An integrative review was conducted based on searches of the LILACS, Medline, and PubMed databases using the following terms: medical workers, healthcare workers, healthcare personnel, and healthcare professionals combined with COVID-19, SARS-CoV-2, 2019-nCoV, n-CoV, and coronavirus, with the Boolean operators “AND” and “OR”. A total of 710 publications were identified, 18 of which were selected for the review, totaling 2,208 infected health professionals in eight countries. It was observed that 67.4% (n = 1,489) of these professionals were women, and 39.4% of the population described in the 15 studies that provided information on occupation (n = 811) were nurses. Seven publications (n = 553) reported severity, among which the most prevalent category was mild/common (47.3% of cases; n = 213). The most common comorbidities were migraine (9.6%, n = 87 of 906), systemic arterial hypertension (5.5%, n = 78 of 1,427), and chronic obstructive pulmonary disease (3.7%, n = 52 of 1,399). The most common symptoms were coughing (34.3%, n = 597 of 1,740), headache (36.8%, n = 582 of 1,583), and myalgia (31.6%, n = 544 of 1,720). The most frequent radiological findings were bilateral involvement (34.5%, n = 139 of 403), ground glass (49%, n = 101 of 206), and bilateral pneumonia (77.4%, n = 65 of 84). The study found that the most often affected health professionals were female nursing professionals, the main symptom was coughing, and the most frequent comorbidity was migraine. The study’s limitation is the small sample. There is a need for more studies with these professionals.

Introduction

In December 2019, China reported the first cases of coronavirus 19 disease (COVID-2019) in Wuhan, Hubei province. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS CoV 2), which is transmitted from human to human in aerosols produced when infected people cough.¹ Sequencing of the virus showed that the nCoV-2019 genome is 96.2% similar to the bat coronavirus and 79.5% similar to the coronavirus that causes SARS.²

On March 11, 2020, the World Health Organization (WHO) declared COVID 19 a pandemic in response to generalized global transmission.³ Up to July 31, 2020, 17.3 million cases of COVID 19 and 592 thousand deaths had been confirmed, according to the Johns Hopkins University Center for Systems Science and Engineering.⁴ The United States had the highest numbers of cases and deaths, with 4,496,737 confirmed cases and 157,064 deaths. Brazil was in second position in absolute number of cases, 2,610,102.⁴

In the current scenario, the role played by health professionals such as physicians, nurses, nutritionists, physiotherapists, and technicians is of fundamental importance. These professionals work on the front line and are facing increased working hours in order to meet the current emerging demand for care. Additionally, their own health and that of their families is put at risk because of their close contact with patients infected by SARS CoV 2.⁵

In order to protect their professionals, healthcare institutions are instructed to implement strategies for testing, managing, and monitoring professionals with flu-like symptoms, and for correct use of personal protective equipment (PPE).⁶ However, the atypical nature of the pandemic, compounded by health system deficiencies increases the likelihood that these professionals will come into contact with people infected by COVID 19, both regularly and intermittently, thereby increasing their risk of infection.⁵

According to the Brazilian Ministry of Health’s Biological Agents Risk Classification, the SARS CoV 2 virus is a class 3 agent, i.e. it involves moderate risk to the community and high individual risk.⁷ It has been reported by the Centers for Disease Control and Prevention (CDC) that around 11% of those infected by SARS CoV 2 are health professionals.⁸

A study published in The Lancet showed that health professionals’ risk of infection by the novel coronavirus is considerably different to other groups’ risk. Professionals working in infirmaries or hospitals are exposed to a high risk of infection. Compounding this, health professionals’ risk of infection by SARS CoV 2 is tripled by incorrect use of PPE, by having a family member infected with COVID 19, and by poor compliance with measures for prevention and control of infections.⁸

It is estimated that a million health professionals are working on the front line against COVID 19. The majority of them are nurses. According to the American Nurses Association, around 20 million nurses are working to combat the pandemic worldwide. According to the International Council of Nurses (ICN), by May of 2020, approximately 260 nurses had died and more than 90 thousand health professionals had been infected by COVID 19 in 30 countries.⁹

Preventing SARS CoV 2 infections among health professionals is important for countries’ actions to cope with COVID 19. Infections among these workers reduces the workforce and contributes to worse patient care.¹⁰ In view of this, the objective of this study is to analyze the clinical and epidemiological profile of health professionals with COVID 19.

Methods

The study design is an integrative literature review of the clinical and epidemiological characteristics of health professionals infected by COVID 19 worldwide. Articles were selected for the review by searching the LILACS, MEDLINE, and PubMed databases. An initial search was conducted using the keywords medical workers, healthcare workers, healthcare personnel, and healthcare professionals, in the title, combined with COVID 19, SARS CoV 2, 2019-nCoV, n-CoV, and coronavirus. The Boolean operators “AND” and “OR” were used to construct the search strings. With the objective of refining the search, a second search was conducted employing the terms from the first search with the addition of “clinical features OR clinical characteristics”. The period analyzed was January 1, 2020 to September 13, 2020. Manual searches were also performed of the references of each article.

In this study, the aim was to identify the clinical and epidemiological characteristics of health professionals infected by SARS CoV 2. The following variables were analyzed: country of study, study population, sex (male or female), occupation (physician, nurse, or others), clinical manifestations, comorbidities, radiological findings, and severity of COVID 19.

Cohort studies, cross-sectional studies, case series, letters to the editor, and articles published in any language were included. Government epidemiological bulletins, literature reviews, and publications for which the full text was not available were excluded from the study.

Five researchers were responsible for searching for scientific publications. Later, the same researchers read titles and abstracts to select potentially eligible studies. Afterwards, the full texts were read, data were collected on the variables, and a database was constructed.

The researchers constructed a database for the data extracted. Data were input and then checked by one of the researchers. The same researcher who checked the database was also responsible for systematization/analysis of the data.

The first search, using the keywords medical workers, healthcare workers, healthcare personnel, and healthcare professionals in the title, combined with COVID 19, SARS CoV 2, 2019-nCoV, n-CoV, and coronavirus, identified 710 scientific publications in the databases. In order to refine the search, reducing the number of articles, “clinical features OR clinical characteristics” was added to the search string, which reduced the number of studies from 710 to 58. After the selection stages, 18 articles were eligible and were included in the study.

The low number of studies is because of the rarity of scientific publications that exclusively deal with the subject of the epidemiological profile of health professionals infected by COVID 19. A considerable number of studies reported statistical data on this group of professionals together with other groups, making it difficult to separate the information needed for this article. Moreover, a large proportion of articles investigating health professionals only dealt with mental health problems.

Results

The articles included covered a total of 2,208 health professionals who had been infected by COVID 19 in eight different countries (Figure 1), as follows: China (8 texts; 457 people infected), United States (3 texts; 283 people infected), Holland (2 texts; 176 people infected), Italy (2 texts; 83 people infected), India and Singapore (1 text; 906 people infected), Spain (1 text; 213 people infected), and the United Kingdom (1 text; 90 people infected) (Table 1).

Figure 1.

Flow diagram illustrating selection of the articles included in the study, 2020.

Table 1.

Characteristics of health professionals with coronavirus 2019 disease (COVID-19), 2020

Article	Countries	n	Sex (%)		Occupations reported (%)				Deaths (n)	Needed ICU
			Male	Female	Physicians	Nurses	Others	Information not provided
Wei et al.1	China	12	25.0	75.0	8.3	91.7	0.0	0.0	0	Not reported
Liu et al.23	China	30	33.3	66.7	73.3	26.7	0.0	0.0	0	Not reported
Wang et al.24	China	80	38.7	61.3	28.7	51.3	20.0	0.0	1	4
Tostmann et al.6	Holland	90	21.1	78.9	23.3	34.5	42.2	0.0	Not reported	Not reported
Chu et al.25	China	54	66.7	33.3	Not reported	Not reported	Not reported	100.0	1	1
Chow et al.26	United States	48	22.9	77.1	Not reported	Not reported	Not reported	100.0	Not reported	Not reported
McMichael et al.3	United States	50	24.0	76.0	Not reported	Not reported	Not reported	100.0	0	Not reported
Lai et al.14	China	110	28.2	71.8	23.6	56.4	20.0	0.0	1	Not reported
Chew et al.20	Singapore and India	906	35.6	64.4	29.6	39.2	31.2	0.0	Not reported	Not reported
Kluytmans-van den Bergh et al.27	Holland	86	17.4	82.6	0.0	27.9	58.1	14.0	Not reported	Not reported
Durante-Mangoni et al.28	Italy	3	33.3	66.7	0.0	100.0	0.0	0.0	Not reported	Not reported
Jin et al.29	China	103	37.8	62.2	39.8	53.4	6.8	0.0	Not reported	Not reported
Xiong et al.30	China	43	51.2	48.8	39.6	32.5	27.9	0.0	Not reported	Not reported
Garzaro et al.31	Italy	80	31.2	68.8	42.5	35.0	21.2	1.3	Not reported	Not reported
Wang et al.32	China	25	32.0	68.0	0.0	0.0	0.0	100.0	Not reported	Not reported
Mani et al.33	United States	185	38.8	61.6	0.0	0.0	0.0	100.0	Not reported	Not reported
Jones et al.34	United Kingdom	90	22.2	77.8	15.6	48.9	35.5	0.0	Not reported	Not reported
Súarez-García et al.35	Spain	213	19.7	80.2	30.0	63.4	6.5	0.0	0	1
Total (n [%])	-	2,208	721	1,489	531	811	469	375	-	-
		100.00	32.60	67.40	24.00	36.70	21.30	16.90	-	-

ICU = intensive care unit.

The total population analyzed comprised 67.4% (n = 1,489) females. The most common professional activity among those infected was nursing, with 36.7% of the sample in the 15 studies that provided this information (total population = 2,056; 39.4%; n = 811) about the individuals infected. Seven articles did not state what job some of the professionals infected performed at the healthcare institution. These people accounted for 16.9% (n = 375) of the population analyzed and were assigned to the “information not provided” column (Table 1).

In those publications that provided information on associated comorbidities, the most common comorbidities, in terms of the proportion of those infected who presented them, were: migraine (one study; total population = 906; symptom present in 9.6%; n = 87), systemic arterial hypertension (seven studies; total population = 1,427; symptom present in 5.5%; n = 78), chronic obstructive pulmonary disease (five studies; total population = 1,399; symptom present in 3.7%; n = 52), obesity (one study; total population = 50; symptom present in 62%; n = 31). Hyperlipidemia and smoking were reported in one study, with a total population of 906 and these variables were present in 3.2%, n = 29 (Table 2).

Table 2.

Clinical and epidemiological profile of health professionals with coronavirus 2019 disease (COVID-19), 2020

	Nº studies	Population (n)	Had symptom		Range (%)
			n	%
Comorbidities
Migraine	1	906	87	9.6	9.6
Systemic arterial hypertension	7	1,427	78	5.5	3.8-12.5
Chronic obstructive pulmonary disease	5	1,399	52	3.7	1.3-4.4
Obesity	1	50	31	62.0	62.0
Hyperlipidemia	1	906	29	3.2	3.2
Smoking	1	906	29	3.2	3.2
Diabetes	6	1,317	24	1.8	0.5-10.0
Cardiovascular diseases	6	1,402	20	1.4	0.4-8.0
Kidney disease	2	190	5	2.6	1.8-3.8
Lung disease	2	75	4	5.3	4.0-8.0
Liver disease	1	80	2	2.5	2.5
Cerebrovascular diseases	2	986	2	0.2	0.1-1.3
Symptoms
Coughing	13	1,740	597	34.3	16.9-100.0
Headache	10	1,583	582	36.8	10.0-71.1
Myalgia	12	1,720	544	31.6	1.9-100.0
Sore throat	8	1,582	523	33.1	1.9-50.8
Fever	13	924	491	53.1	17.5-100.0
Fatigue	6	1,378	479	34.8	16.7-61.6
Coryza	4	1,130	203	18.0	12.5-53.5
Myalgia or general malaise	2	196	152	77.6	60.0-100.0
Dyspnea	9	1,444	148	10.2	6.2-46.7
Nausea or vomiting	7	1,398	132	9.4	1.9-16.7
Expectoration	3	1,040	124	11.9	5.6-23.8
Diarrhea	9	701	106	15.1	5.6-75.0
Malaise	2	134	70	52.2	10.4-75.6
Chest tightness	3	243	47	19.3	7.4-29.1
Lethargy	1	103	44	42.7	42.7
Loss of sense of smell or taste	4	354	38	10.7	5.0-33.3
Fatigue or systemic pain	1	30	21	70.0	70.0
Loss of appetite	1	86	15	17.4	17.4
Joint pain	1	103	11	10.7	10.7
Chills or shivers	2	102	9	8.8	3.7-14.6
Allergy	1	90	8	8.9	8.9
Sore throat	1	12	7	58.3	58.3
Abdominal pains	1	86	5	5.8	5.8
Acute respiratory distress syndrome	1	80	4	5.0	5.0
Anorexia	2	102	4	3.9	3.9
Hoarseness	1	4	2	50.0	50.0
Nervousness	1	54	1	1.9	1.9
Rhinorrhea	1	54	1	1.9	1.9
Globus pharyngeus	1	54	1	1.9	1.9
Disease severity
Mild/common	3	450	213	47.3	2.3-86.6
Moderate	1	366	155	42.3	23.9-97.7
Mild/moderate	1	103	98	95.1	95.1
Severe	4	297	60	20.2	3.9-74.1
Critical	3	267	8	3.0	0.9-5.5
Radiological findings			Had finding
Bilateral involvement	3	403	139	34.5	5.2-98.8
Ground glass	4	206	101	49.0	13.3-100.0
Bilateral pneumonia	2	84	65	77.4	63.3-85.2
Consolidation	4	219	61	27.9	11.1-55.8
Fibrous streaks	2	97	46	47.4	44.2-50.0
Unilateral pneumonia, right	1	54	27	50.0	50.0
Unilateral pneumonia, left	1	54	25	46.3	46.3
Interstitial thickening	2	97	25	25.8	5.6-51.2
Irregular shadows	1	54	22	40.7	40.7
Pleural thickening	1	54	14	25.9	25.9
Reticulonodular changes	2	66	14	21.2	16.7-22.2
Lymphedema	1	54	13	24.1	24.1
Nodules	1	54	12	22.2	22.2
Pleural effusion	3	109	12	11.0	8.3-14.0
Unilateral pneumonia, side not specified	1	30	11	36.7	36.7
Unilateral involvement	1	213	7	3.3	3.3

The five most common symptoms reported, in terms of the number of infected people who exhibited them, were coughing (13 studies; total population = 1,740; symptom present in 34.3%; n = 597), headache (10 studies; total population = 1,583; symptom present in 36.8%; n = 582), myalgia (12 studies; total population = 1,720; symptom present in 31.6%; n = 544), sore throat (8 studies; total population = 1,582; symptom present in 33.1%; n = 523), and fever (13 studies; total population = 924; symptom present in 53.1%; n = 491) (Table 2). Severity was not specified in 74.9% (n = 1,655) of the cases reported. In the seven publications (total population = 553) that did provide data on the severity of cases of the disease, the most prevalent category was mild/common cases (three studies; total population = 450; mild/common severity present in 47.3%; n = 213) (Table 2).

Five articles provided information on radiological findings, in which the most common findings in imaging exams were: bilateral involvement (three studies; total population = 403; symptom present in 34.5%; n = 139), ground glass (four studies; total population = 206; symptom present in 49%; n = 101), bilateral pneumonia (two studies; total population = 84; symptom present in 77.4%; n = 65), consolidations (four studies; total population = 219; symptom present in 27.9%; n = 61), and fibrous streaks (two studies; total population = 97; symptom present in 47.4%; n = 46) (Table 2).

Discussion

It is important to determine the clinical and epidemiological profile of health professionals with COVID 19 in order to understand the consequences of the pandemic for the health of professionals who work on the front line. It is known that the workforce is heterogeneous and that, because of this, there are different degrees of exposure to the virus and of sickness at health services. Therefore, identifying those who are the most vulnerable in these settings enables efforts to be focused on these groups.⁹

According to data from the ICN, up to May 5, 2020, around 90 thousand healthcare professionals, in particular nurses, had been infected with the novel coronavirus worldwide.⁹ This large number of infected health professionals is understandable if we analyze the forms of viral transmission. These forms of contagion can be defined as community, when they presuppose circulation of the virus in the community, or occupational, when the virus is transmitted to workers who are exposed during their work.^10,11

Community contagion can be explained by inadequate maintenance of safe distancing.¹² This is why the WHO recommends using masks in public environments and that people stay at home to reduce transmission of SARS CoV 2. Nevertheless, these recommendations do not encompass essential activities, such as those carried out by health professionals, since their jobs are indispensable to ensuring care for the various different health problems.¹¹

This difference implies that the high rates of contagion among health professionals can be explained by occupational transmission, considering that health professionals who have no training in protection are reallocated to treat patients with COVID 19, and also by the lack or incorrect use of PPE, which can potentialize the viral transmission chain.¹³ Of particular importance are appropriate use of PPE and, primarily, correct disposal of PPE.¹⁴ However, it should be pointed out that, despite the high risk of the forms of contagion mentioned, this article does not present sufficient data to establish a statistical relationship.

With regard to the sex of the professionals who have been infected, this analysis identified a predominance among females. This may be related to the large numbers of these professionals in hospitals and because this is an occupation that is historically performed to a great extent by women, since analyses of the general population do not report evidence that the virus has a predilection for one or other of the sexes.^15-17 The female predominance is in line with a study¹⁶ that was conducted with health professionals only in Wuhan, China, in which 61.25% of the 88 patients were women.¹⁶

With regard to the roles of these health professionals, nurses made up the largest proportion of those infected (15 studies, total population = 2,056, 39.4% [n = 811] of infected health professionals were nurses), followed by physicians (15 studies, total population = 2,056, 25.8% [n = 531] of the infected health professionals were physicians), and then a category designated as “others” (15 studies, total population = 2,056, 22.8% [n = 469] of the infected health professionals were classified as “others”), which is not defined in the texts. However, it is suggested that this category includes nursing auxiliaries and technicians and physiotherapists, since these are professionals who naturally have a great deal of contact with intensive care units (ICU).

Although few studies provide information about deaths or the need for intensive care, those that did report a low rate of admission to ICUs among health professionals and a low number of deaths. One probable explanation is that the majority of these health professionals who were infected with COVID 19 had mild cases, similar to information available in the literature, showing that the majority of infected people have mild symptoms of the disease, although there is little data on severity of cases in the articles analyzed because 74.9% of the total sample of studies did not report these data.

As reported in a series of COVID 19 cases registered in continental China (72,314 cases on February 11, 2020), no deaths occurred among mild cases, whereas the overall lethality rate among critical cases was 49%. This rate increased among those with underlying chronic diseases.¹⁸ This is another possible explanation for the low mortality rate and low rate of admission to ICU in this group, because health professionals account for a small proportion of the sample in studies that provide information on associated comorbidities. Investigations about the prevalence of comorbidities among health professionals should be conducted to enable this hypothesis to be better understood.

Another factor that could explain the low severity among health professionals is related to early identification of symptoms by the professionals themselves, since they have the clinical experience to be able to identify their own symptoms more easily.^14,19 This access to clinical knowledge and, consequently, to diagnosis, reduces the time between onset of symptoms and confirmation of infection among health professionals, which could also explain the low frequency of severe symptoms, since the disease is probably detected and treated when the first symptoms emerge, avoiding the consequences of exacerbation of the infection.

According to studies conducted with professionals in India and Singapore, headache and migraine were the second most common symptom and the most common comorbidity among the health professionals, respectively.²⁰ It is probable that the predominant complain of headache may be linked with exacerbation of a preexisting condition or with the new PPE worn by these professionals during theCOVID 19 pandemic, as reported in other studies, in which 81% of interviewees reported headache related to use of new PPE.²¹

The high incidence of headache after infection by SARS CoV 2 and the presence of migraine as an underlying chronic condition among health professionals may also reflect the psychological impact this group has suffered during the COVID 19 pandemic.²⁰ Fear of transmitting the infection to other professionals and to relatives, compounded by the dilemma surrounding taking sick leave in a healthcare sector that is already overloaded, may increase levels of psychological suffering, exacerbating this symptom.

The limitations of this study include the small sample size. Data were analyzed on just 2,208 health professionals infected by SARS CoV 2 in studies from eight countries, which is a small number compared to the dimensions of the impact of the pandemic, since knowledge about how these workers are exposed to the virus will be essential to protect front-line healthcare teams.²²

Finally, with regard to the variables analyzed, such as the occupations of these health professionals, the levels of disease severity, need for admission to an ICU, and the number of deaths, few studies explored these variables in detail, which limited the results of the study. Differences in definition of data made it impossible to present the variable age, for example, which was reported as median, mean, and age ranges. This lack of standardization could be addressed in future studies, improving understanding of the true profile of infected professionals and their needs.

Conclusions

Even with the limitations imposed by the small sample of health professionals, it was possible to trace the clinical and epidemiological profile of these health professionals, the majority of whom were female and nurses. Nevertheless, the fact that this study only employed absolute numbers makes it difficult to interpret the results and draw conclusions on these aspects, because of the need to employ indicators to make it possible to compare data.

The main clinical manifestations reported showed that coughing was the most common symptom and migraine was the most frequent comorbidity. With regard to disease severity, the majority of cases were mild/common and bilateral pulmonary involvement ground glass were the most common radiological findings.

This study attests to the difficulty in obtaining the epidemiological data needed to determine the profile of disease caused by SARS CoV 2 among front-line health professionals. There is an evident need for more studies related to infections among health professionals that are free of limitations and cover the clinical and epidemiological features of COVID 19 among these professionals who are so important in the pandemic.