its just a literature review on this specific article. apa format. I attached the article and an outline to go by
International Journal of Infectious Diseases 104 (2021) 335–346
Contents lists available at ScienceDirect
International Journal of Infectious Diseases
journal homepage: www.elsevier.com/locate/ijid
COVID-19 and healthcare workers: A systematic review and
meta-analysis
Mandana Gholamia , Iman Fawada , Sidra Shadana , Rashed Rowaieea ,
HedaietAllah Ghanema , Amar Hassan Khamisb , Samuel B. Hoa,c,*
a
College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Healthcare City, Dubai, United Arab Emirates
Hamdan Bin Mohammed College of Dental Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Healthcare City, Dubai,
United Arab Emirates
c
Department of Medicine, Mediclinic City Hospital, Dubai Healthcare City, Dubai, United Arab Emirates
b
A R T I C L E I N F O
A B S T R A C T
Article history:
Received 11 November 2020
Received in revised form 5 January 2021
Accepted 6 January 2021
Background: The COVID-19 pandemic has focused attention on the challenges and risks faced by frontline
healthcare workers (HCW). This study aimed to describe the clinical outcomes and risk factors for SARSCoV-2 infection in HCW.
Methods: Three databases were surveyed and 328 articles were identified. Of these, 225 articles did not
meet inclusion criteria; therefore, 97 full-text article were reviewed. Finally, after further revision, 30
articles were included in the systematic review and 28 were used for meta-analysis.
Results: Twenty-eight studies were identified involving 119,883 patients. The mean age of the patients
was 38.37 years (95% CI 36.72–40.03) and males comprised 21.4% (95% CI 12.4–34.2) of the population of
HCW. The percentage of HCW who tested positive for COVID-19 was 51.7% (95% CI 34.7–68.2). The total
prevalence of comorbidities in seven studies was 18.4% (95% CI 15.5–21.7). The most prevalent symptoms
were fever 27.5% (95% CI 17.6–40.3) and cough 26.1% (95% CI 18.1–36). The prevalence of hospitalisation
was 15.1% (95% CI 5.6–35) in 13 studies and of death was 1.5% (95% CI 0.5–3.9) in 12 studies. Comparisons
of HCW with and without infection showed an increased relative risk for COVID-19 related to personal
protective equipment, workplace setting, profession, exposure, contacts, and testing.
Conclusion: A significant number of HCW were reported to be infected with COVID-19 during the first 6 months
of the COVID-19 pandemic, with a prevalence of hospitalisation of 15.1% and mortality of 1.5%. Further data are
needed to track the continued risks in HCW as the pandemic evolves and health systems adapt.
© 2021 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an
open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords:
COVID-19
SARS-CoV2
Healthcare workers
Meta-analysis
Occupational health
Infectious disease transmission
Introduction
On 21 December 2019, a pneumonia-like outbreak of an
unknown cause or origin was found to be emerging in Wuhan,
Hubei Province, China. Due to the rapidly increasing cases and
unclear protocol regarding medical care, bronchoalveolar lavage
samples of patients were isolated and analysed by 03 January
2020. The reports showcased a new strain of coronavirus,
initially termed 2019-nCoVs by the Chinese Center for Disease
Control and Prevention (CDC) (Zhang, 2020) and then later
named SARS-CoV-2 by the International Committee on Taxonomy of Viruses. On 11 March 2020, the World Health Organization
* Corresponding author at: Mohammed Bin Rashid University of Medicine and
Health Sciences, Building 14, Dubai Healthcare City, PO Box 505055, Dubai, United
Arab Emirates.
E-mail address: samuel.ho@mbru.ac.ae (S.B. Ho).
declared the COVID-19 outbreak a pandemic, sending millions
into a state of panic and emergency, with many federal
governments developing strategies to protect their citizens
(World Health Organization).
With limited understanding of this novel coronavirus strain and
being at the frontline, healthcare workers (HCW) were soon
deemed as one of the groups with the highest risk of exposure to
COVID-19 infection. By late January 2020, CDC China reported
transmission of COVID-19 to 16 healthcare workers, as a result of
being in contact with patients from the outbreak (Li, 2020c). It was
speculated that HCW infection could potentially contribute to
exacerbating the chain of transmission in hospitals and outside
health facilities, and therefore proper protection of HCW against
COVID-19 through mandating protective protocols had to be
prioritised (Black et al., 2020).
Along with focusing on the impact of COVID-19 on the general
population, numerous studies have since been published in
different parts of the world outlining the implication of this virus
https://doi.org/10.1016/j.ijid.2021.01.013
1201-9712/© 2021 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an open access article under the CC BY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
M. Gholami, I. Fawad, S. Shadan et al.
International Journal of Infectious Diseases 104 (2021) 335–346
on healthcare systems, pertaining to the challenges and risks faced
by the frontline and high-risk HCW. The focus of these research
studies has ranged from describing clinical characteristics of HCW
with COVID-19, investigating the risk factors involved in acquiring
the infection, transmission dynamics among HCW, to stating the
observed complications and outcomes of the infection.
This study aimed to combine a systematic review of the
published data, with a meta-analysis to determine the risk and
clinical outcomes of infection in HCWs at the frontline of
diagnosing and caring for COVID-19 infected patients. Furthermore, as part of the qualitative discussion, it aimed to explore the
risk factors that may have been involved in the transmission of
COVID-19 to HCW.
Information sources and search strategy
PubMed, Scopus and Google Scholar were the three databases
that were searched, from 01 May to 09 July 2020, by five
independent researchers. All five researchers independently
evaluated the search results after finishing the database search
process. The search keywords were broadly grouped into four
categories: “healthcare”, “risk”, “COVID-19” and “miscellaneous”
(Supplementary Table 1).
Eligibility criteria
Full-text, peer reviewed articles from 01 January to 09 July 2020
discussing SARS-CoV-2 only amongst HCW populations were included.
Articles that were not in English or an English translation was not
available, and articles without comprehensive data, comments or
viewpoints related to HCW were excluded from the analysis.
Methods
Study protocol
The protocol for this study was generated according to
the Preferred Reporting Items for Systematic Reviews and
Meta-Analysis Protocols (PRISMA-P) recommendations. The
PRISMA checklist was used to guide the reporting (Shamseer
et al., 2015).
Study selection
Full texts of the selected articles were compared with the predetermined inclusion and exclusion criteria after the initial search
results were screened by title and abstract.
Figure 1. PRISMA flowchart of study selection process.
336
M. Gholami, I. Fawad, S. Shadan et al.
International Journal of Infectious Diseases 104 (2021) 335–346
sputum, headache, haemoptysis, sore throat, diarrhoea, nausea
and vomiting), blood investigations (anaemia, white blood cells,
high lactate dehydrogenase (LDH), C-reactive protein (CRP),
erythrocyte sedimentation rate (ESR), and high creatinine),
complications (unilateral pneumonia, bilateral pneumonia, reactive airway disease, RNA anaemia, shock, hospitalisation, discharge
and death) were extracted to Microsoft Excel. Data were screened
by a single researcher for duplicates. For the qualitative analysis of
the study, 30 articles were thoroughly reviewed by six independent researchers to identify risk factors contributing to COVID-19
infection of HCW.
Data collection
The following variables were obtained for all the selected
papers: name of authors, year and date of publication, study
design, publishing country, and total number of HCW in the study.
Regarding the quantitative part of the study, information from the
selected articles was extracted by the five independent researchers
and then pooled together. Data pertaining to demographics (age
and gender), comorbidities (diabetes mellitus, cardiovascular
disease (CVD), chronic obstructive pulmonary disease (COPD),
and hypertension), clinical manifestations (fever, cough, fatigue,
Table 1
Summary of characteristics of articles included in the study.
No.
Author
Journal
Date
(MM/YY)
Country
Study type
N (total
population)
N HCW with
COVID-19
Quality
score
Reference
1
Zhan et al.
N Engl J Med
02/20
China
23
23
8
Zhan (2020)
2
Chu et al.
J Med Virol
03/20
China
54
38
10
Chu (2020)
3
4
Xing et al.
Marjolein et al.
Euro Surveill
JAMA Netw Open
03/20
03/20
China
Netherlands
2
1353
2
86
8
8
Xing et al. (2020)
Marjolein (2020)
5
Zheng et al.
Clin Infect Dis
03/20
China
2457
2457
8
Zheng et al. (2020)
6
Li YK et al.
Curr Med Sci
03/20
China
148
12
10
Li et al. (2020)
7
Reusken et al.
Euro Surveill
03/20
Netherlands
1097
45
10
Reusken et al. (2020)
8
Ran et al.
Clin Infect Dis
03/20
China
72
28
11
Ran et al. (2020)
9
N Engl J Med
03/20
50
9
McMichael (2020)
J Infect
03/20
United States of
America
China
50
10
McMichael
et al.
Sun et al.
32
32
7
Sun et al. (2020)
11
Burrer et al.
04/20
8945
8495
10
Burrer (2020)
12
Wei et al.
14
12
10
Wei et al. (2020)
13
Kimball et al.
1
9
Kimball et al. (2020)
Wang et al.
04/20
United States of
America
China
–
14
MMWR Morb Mortal
Wkly Rep
J Microbiol Immunol
Infect
MMWR Morb Mortal
Wkly Rep
J Hosp Infect
80
80
8
Wang et al. (2020)
15
Dtsch Arztebl Int
04/20
Germany
957
52
9
16
Schwierzeck
et al.
Canova et al.
Swiss Med Wkly
04/20
Switzerland
21
0
8
Schwierzeck et al.
(2020)
Canova et al. (2020)
17
Tostmann et al.
Euro Surveill
04/20
Netherlands
803
90
9
18
04/20
43
8
264
101
9
20
Nguyen et al.
Lancet Public Health
05/20
99,795
1922
11
Tostmann et al.
(2020)
Heinzerling et al.
(2020)
Breazzano et al.
(2020)
Nguyen et al. (2020b)
21
22
Lai et al.
Chow et al.
JAMA Netw Open
JAMA Netw Open
05/20
05/20
110
48
110
48
9
8
Lai et al. (2020)
Chow et al. (2020)
23
Korth et al.
J Clin Virol
05/20
United States of
America
United States of
America
United States of
America
China
United States of
America
Germany
43
19
Heinzerling
MMWR Morb Mortal
et al.
Wkly Rep
Breazzano et al. J Clin Invest
316
5
9
Korth et al. (2020)
24
Felice et al.
05/20
Italy
388
18
9
Felice et al. (2020)
25
Jin et al.
J Community Health
Res
Mil Med Res
05/20
China
103
84
8
Jin et al. (2020)
26
Cabas et al.
Res Social Adm Pharm 05/20
Italy
1632
15
9
Cabas et al. (2021)
27
Chen et al.
J Infect
05/20
China
105
18
11
Chen et al. (2020)
28
Garzaro et al.
Med Lav
05/20
Italy
830
80
9
Garzaro et al. (2020)
29
Guo et al.
J Bone Joint Surg Am
05/20
China
24
24
10
Guo et al. (2020)
30
RiveraIzquierdo et al.
Int J Environ Res Public 06/20
Health
Spain
Crosssectional
Retrospective
cohort
Case series
Crosssectional
Crosssectional
Retrospective
cohort
Crosssectional
Retrospective
cohort
Retrospective
cohort
Crosssectional
Crosssectional
Prospective
cohort
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Prospective
cohort
Case-series
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Crosssectional
Prospective
cohort
Crosssectional
Crosssectional
Prospective
cohort
76
76
11
Rivera-Izquierdo
et al. (2020)
04/20
04/20
04/20
United States of
America
China
337
M. Gholami, I. Fawad, S. Shadan et al.
International Journal of Infectious Diseases 104 (2021) 335–346
literature retrieval flowchart is represented in Figure 1. During the
initial phase of the search, 328 articles were identified; 33
duplicates were removed. After screening the abstracts, 198
articles were further excluded due to failure to meet the inclusion
criteria. Ninety-seven full-text articles were downloaded and
reviewed. Of these, 67 were excluded due to lack of sufficient data,
comment or viewpoint, as well as three articles that were in
languages other than English and where an English translation of
the article was not available. The final count of articles for
systematic review was 30, and 28 of those articles, published from
February 2020 to June 2020, were used for meta-analysis (Figure 1
and Table 1).
Table 1 provides a summary of characteristics of the included
articles. A great variety of articles from different countries were
noted: 13 were from China, seven from USA, three each from
Netherlands and Italy, two from Germany, and one from Spain. The
most common study type amongst the articles was cross-sectional
(n = 19) and the remaining were a mix of retrospective and
prospective cohort studies, with the exception of one case-series
article (Table 1).
Twenty-nine variables were included in the meta-analysis
(Tables 2–6). Most of the studies showed considerable heterogeneity (I2 > 75%) (Table 2). Fewer studies had evidence of bias, as
demonstrated by Egger’s test (p > 0.05) (Table 2).
Statistical approach
The distribution of the categorical dichotomous variables was
described by calculating percentages. The mean and 95% confidence intervals (CI) were calculated for continuous data. For
studies reporting the mean with 95% CI or the range of the data, the
formula (upper limit-lower limit)/4 was used to extract the
standard deviation. Meta-analysis using the random-effect model
was performed to estimate the pooled prevalence and 95% CI. The
pooled percentage, prevalence and corresponding 95% CI were
calculated in order to indicate the weighted effect size for all binary
variables. The measure of heterogeneity was reported by including
Cochran’s Q statistics and I2 index, with the level of heterogeneity
defined as poor 50, and high >75, and the Tau
square (T2) test. Publication bias was assessed with a funnel plot
and Egger’s test.
Results
Search results
Three databases–PubMed, Scopus and Google Scholar–were
searched from 01 May 2020 to 09 July 2020 using predefined
keywords and a search strategy (Supplementary Table 1). The
Table 2
Meta-analysis of healthcare workers.
Prevalence%
95% CI
n
Q
I2
T2
p-value
Egger’s test
Demographical characteristics
Age (years, mean)
24
Male
27
Comorbidity
7
DM
9
Hypertension
7
CVD
5
COPD
5
38.73
21.4
18.4
1.5
2.5
2.4
2.4
37.83–39.63
12.4–34.2
15.5–21.7
0.3–8.2
0.2–27.9
0.7–7.5
0.9–6.4
23
26
6
8
6
4
4
2,326.49
7,356.1
25.30
763.46
584.15
8.01
6.83
99.01
99.6
76.29
98.95
98.90
50.06
41.43
3.104
2.796
0.0.037
6.311
12.69
0.878
0.519