Dynamics of SARS-CoV-2 RT-PCR positivity and seroprevalence among high-risk healthcare workers and hospital staff

High seroprevalence of severe acute respiratory syndrome coronavirus 2 among healthcare workers in Yaoundé, Cameroon after the first wave of Covid-19 pandemic and associated factors

BACKGROUND

Healthcare workers (HWs) are at a high risk of exposure to emerging health threats. Following the first wave of the coronavirus disease 2019 pandemic in Cameroon, we explored the presence and persistence of naturally acquired antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the factors associated with seropositivity in HWs.

METHODS

Staff at two referral hospitals in Yaoundé or two Health District Hospitals in Obala and Mbalmayo were included in a 6-month prospective cohort analysis or cross-sectional survey, respectively. Seroprevalence and associated factors were determined, and Kaplan-Meier curves and Cox proportional hazards models were used to assess antibody persistence or positive seroconversion over time.

RESULTS

From August 2020 to March 2021, 426 HWs (median age: 31 years, interquartile range: 27-37 years; 66.4% female) were enrolled. The overall seroprevalence of anti-SARS-CoV-2 antibodies was 54.0% (95% confidence interval [CI]: 49.1-58.8) and was significantly different between study sites (p = 0.04). Of the 216 HWs included in the 6-month cohort, 109 (50.5%) HWs were seropositive at inclusion; the probability of persistent antibodies or of becoming seropositive was 93.8% (95% CI: 84.2-100) and 78.9% (95% CI: 61.7-88.4), respectively. Seroconversion was associated with study site and occupation but not with infection prevention and control (IPC) practices.

CONCLUSIONS

We observed high seroprevalence of SARS-CoV-2 antibody and seroconversion among HWs associated with occupational risk. This suggests low compliance to the COVID-19 control measures. Continued training and implementation of IPC measures and accelerated preparedness are needed to better tackle future threats.

COVID-19 infection and seroconversion rates in healthcare workers in Lebanon: An observational study

Coronavirus disease 2019 (COVID-19) infection is a recent pandemic. Healthcare workers (HCW) are at high risk of acquiring the infection and transmitting it to others. Seroprevalence for COVID-19 among HCW varies between countries, hospitals in the same country and even among different departments in the same hospital. In this study, we aim to determine the prevalence of severe acute respiratory syndrome coronavirus 2 antibodies and the seroconversion among the HCW in our hospital. A total of 203 HCW were included. The rate of conversion to seropositive was 19.7% in total, with a rate of 13.4% in female versus 25% in male. The seropositivity in the House keeping group was 83%, followed by 45% in the COVID Floor while the seropositivity in the Anesthesia was 4% and the Infection Control 0%. The highest seropositivity rate in the COVID floor, and in the intensive care unit was explained by the long time spent with the patients. While in the inhalation team and the anesthesia, the lower rates of seropositivity was due to the N95 mask wearing the whole time. Seropositivity for COVID-19 in HCW is a major public health concern. Policies should be implemented to better protect HCWs.

Longitudinal SARS-CoV-2 Seroprevalence among Employees in Outpatient Care Services in Hamburg

The risk of SARS-CoV-2 infection is particularly high for healthcare workers during the pandemic. Home care workers visit many different households per shift. Encounters with mostly elderly patients and their relatives increase the potential for the undetected spread of SARS-CoV-2. In order to gain insight into the seroprevalence of SARS-CoV-2 antibodies and possible transmission risks in outpatient care, this follow-up study was conducted with nursing services in Hamburg. The aim was to estimate the dynamics of seroprevalence in this occupational group over a 12-month period, to identify occupation-specific risk factors, and to collect information on the vaccination status of the surveyed nursing staff. Antibody testing for SARS-CoV-2 IgG against the S1 domain (EUROIMUN Analyser I^® Lübeck, Germany) was performed on participating healthcare workers with patient contact at a total of four time points within one year from July 2020 to October 2021 (baseline, follow-up after three, six and twelve months). The data were mostly analysed descriptively. Differences in IgG titres were analysed using variance analysis methods, particularly Tukey's range test. The seroprevalence was 1.2% (8/678) at baseline and 1.5% (9/581) at the three-month follow-up (T1). At the second follow-up (T2) after six months, vaccination against SARS-CoV-2 was available from January 2021 onwards. The prevalence rate of positive IgG antibodies relative to the S1 domain of the spike protein test among unvaccinated individuals was 6.5%. At (T3) after twelve months (July to October 2021), 482 participants were enrolled, and 85.7% of the workers were considered fully vaccinated at this time point, while 51 individuals were unvaccinated. The prevalence was 13.7% (7/51). In our study, a low seroprevalence was found among home care workers, which was lower than in our studies conducted in the clinical setting. Therefore, it can be assumed that the occupational risk of infection is rather low for both the nursing staff and the patients/clients cared for in the outpatient setting. The good provision of protective equipment and the high vaccination rate of the staff probably had a positive influence.

The COVID - AGICT study: COVID-19 and advanced gastro-intestinal cancer surgical treatment. A multicentric Italian study on the SARS-CoV-2 pandemic impact on gastro-intestinal cancers surgical treatment during the 2020. Analysis of perioperative and short-term oncological outcomes

BACKGROUND

This Italian multicentric retrospective study aimed to investigate the possible changes in outcomes of patients undergoing surgery for gastrointestinal cancers during the COVID-19 pandemic.

METHOD

Our primary endpoint was to determine whether the pandemic scenario increased the rate of patients with colorectal, gastroesophageal, and pancreatic cancers resected at an advanced stage in 2020 compared to 2019. Considering different cancer staging systems, we divided tumors into early stages and advanced stages, using pathological outcomes. Furthermore, to assess the impact of the COVID-19 pandemic on surgical outcomes, perioperative data of both 2020 and 2019 were also examined.

RESULTS

Overall, a total of 8250 patients, 4370 (53%) and 3880 (47%) were surgically treated during 2019 and 2020 respectively, in 62 Italian surgical Units. In 2020, the rate of patients treated with an advanced pathological stage was not different compared to 2019 (P = 0.25). Nevertheless, the analysis of quarters revealed that in the second half of 2020 the rate of advanced cancer resected, tented to be higher compared with the same months of 2019 (P = 0.05). During the pandemic year 'Charlson Comorbidity Index score of cancer patients (5.38 ± 2.08 vs 5.28 ± 2.22, P = 0.036), neoadjuvant treatments (23.9% vs. 19.5%, P < 0.001), rate of urgent diagnosis (24.2% vs 20.3%, P < 0.001), colorectal cancer urgent resection (9.4% vs. 7.37, P < 0.001), and the rate of positive nodes on the total nodes resected per surgery increased significantly (7 vs 9% - 2.02 ± 4.21 vs 2.39 ± 5.23, P < 0.001).

CONCLUSIONS

Although the SARS-CoV-2 pandemic did not influence the pathological stage of colorectal, gastroesophageal, and pancreatic cancers at the time of surgery, our study revealed that the pandemic scenario negatively impacted on several perioperative and post-operative outcomes.

The impact of caregivers on nosocomial transmission during a COVID-19 outbreak in a community-based hospital in South Korea

The COVID-19 pandemic becomes a cause of concern for hospital transmission. Caregivers may play an important role as vectors for nosocomial infections; however, infection control for caregivers often is neglected. A nosocomial COVID-19 outbreak occurred in a 768-bed hospital from March 20, 2020, to April 14, 2020. We conducted a retrospective chart review and epidemiologic investigation on all cases. A total of 54 cases of laboratory-confirmed COVID-19 occurred in the community-based hospital. They included 26 (48.1%) patients, 21 (38.9%) caregivers, and 7 (13.0%) healthcare workers. These 21 caregivers cared for 18 patients, and of these, 9 were positive for COVID-19, 6 were negative, and 3 died before testing. Of the 6 negative patients, 3 had no exposure because the caregiver began to show symptoms at least 5 days after their discharge. Of the 9 positive patients, 4 cases of transmission took place from patient to caregiver (one patient transmitted COVID-19 to two caregivers), and 6 cases of transmission occurred from caregiver to patient. Of the 54 hospital-acquired cases, 38 occurred in the 8th-floor ward and 8 occurred in the 4th-floor ward. The index case of each ward was a caregiver. Counting the number of cases where transmission occurred only between patients and their own caregivers, 9 patients were suspected of having exposure to COVID-19 from their own caregivers. Six patients (66.7%) were infected by COVID-19-confirmed caregivers, and 3 patients were uninfected. Fewer patients among the infected were able to perform independent activities compared to uninfected patients. Not only patients and healthcare workers but also caregivers groups may be vulnerable to COVID-19 and be transmission sources of nosocomial outbreaks. Therefore, infection control programs for caregivers in addition to patients and healthcare workers can be equally important.

Chemerin plasma levels are increased in COVID-19 patients and are an independent risk factor of mortality

Background

Chemerin is an extracellular protein with chemotactic activities and its expression is increased in various diseases such as metabolic syndrome and inflammatory conditions. Its role in lung pathology has not yet been extensively studied but both known pro- and anti-inflammatory properties have been observed. The aim of our study was to evaluate the involvement of the chemerin/ChemR23 system in the physiopathology of COVID-19 with a particular focus on its prognostic value.

Methods

Blood samples from confirmed COVID-19 patients were collected at day 1, 5 and 14 from admission to Erasme Hospital (Brussels – Belgium). Chemerin concentrations and inflammatory biomarkers were analyzed in the plasma. Blood cells subtypes and their expression of ChemR23 were determined by flow cytometry. The expression of chemerin and ChemR23 was evaluated on lung tissue from autopsied COVID-19 patients by immunohistochemistry (IHC).

Results

21 healthy controls (HC) and 88 COVID-19 patients, including 40 in intensive care unit (ICU) were included. Plasma chemerin concentration were significantly higher in ICU patients than in HC at all time-points analyzed (p<0.0001). Moreover, they were higher in deceased patients compared to survivors (p<0.05). Logistic univariate regression and multivariate analysis demonstrated that chemerin level at day 14 of admission was an independent risk factor for death. Accordingly, chemerin levels correlated with inflammatory biomarkers such as C-reactive protein and tumor necrosis factor α. Finally, IHC analysis revealed a strong expression of ChemR23 on smooth muscle cells and chemerin on myofibroblasts in advanced acute respiratory distress syndrome (ARDS).

Discussion

Increased plasma chemerin levels are a marker of severity and may predict death of COVID-19 patients. However, multicentric studies are needed, before chemerin can be considered as a biomarker of severity and death used in daily clinical practice. Further studies are also necessary to identify the precise mechanisms of the chemerin/ChemR23 system in ARDS secondary to viral pneumonia.

Perspective on the challenges of COVID-19 facing healthcare workers

The emergence of COVID-19 has caused a significant impact on healthcare workers (HCWs) across the globe. A few of these challenges include high workload, lack of coordination and direction, changing information, shortage of personal protective equipment (PPE), managing isolation, fear, and increased anxiety, adapting to changes in healthcare practice and policy, coping strategies, and emotional and physical needs. Here, we shed light on some aspects of these challenges among healthcare workers.

The role of routine SARS-CoV-2 screening of healthcare-workers in acute care hospitals in 2020: a systematic review and meta-analysis

Background

Healthcare workers (HCW) are at increased risk of infection with SARS-CoV-2. Vulnerable patient populations in particular must be protected, and clinics should not become transmission hotspots to avoid delaying medical treatments independent of COVID. Because asymptomatic transmission has been described, routine screening of asymptomatic HCW would potentially be able to interrupt chains of infection through early detection.

Methods

A systematic search was conducted in the Cochrane COVID-19 Study Register, Web of Science and WHO COVID‐19 Global literature on coronavirus with regard to non-incident related testing of healthcare workers using polymerase chain reaction on May 4th 2021. Studies since January 2020 were included. An assessment of risk of bias and representativeness was performed.

Results

The search identified 39 studies with heterogeneous designs. Data collection of the included studies took place from January to August 2020. The studies were conducted worldwide and the sample size of the included HCW ranged from 70 to 9449 participants. In total, 1000 of 51,700 (1.9%) asymptomatic HCW were tested positive for SARS-CoV-2 using PCR testing. The proportion of positive test results ranged between 0 and 14.3%. No study reported on HCW-screening related reductions in infected person-days.

Discussion and conclusions

The heterogeneous proportions might be explained by different regional incidences, lock-downs, and pre-analytical pitfalls that reduce the sensitivity of the nasopharyngeal swab. The very high prevalence in some studies indicates that screening HCW for SARS-CoV-2 may be important particularly in geographical regions and pandemic periods with a high-incidence. With low numbers and an increasing rate of vaccinated HCW, a strict cost–benefit consideration must be made, especially in times of low incidences. Since we found no studies that reported on HCW-screening related reductions in infected person-days, re-evaluation should be done when these are available.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07554-5.

SARS-CoV-2 Vaccination Rate and SARS-CoV-2 Infection of Health Care Workers in Aerosol-Generating Medical Disciplines

Healthcare workers (HCW) who perform aerosol-generating procedures (AGP) are at high risk of SARS-CoV-2 infection. Data on infection rates and vaccination are limited. A nationwide, cross-sectional study focusing on AGP-related specialties was conducted between 3 May 2021 and 14 June 2021. Vaccination rates among HCW, perception of infection risk, and infection rates were analyzed, focusing on the comparison of gastrointestinal endoscopy (GIE) and other AGP-related specialties (NON-GIE), from the beginning of the pandemic until the time point of the study. Infections rates among HCW developed similarly to the general population during the course of the pandemic, however, with significantly higher infections rates among the GIE specialty. The perceived risk of infection was distributed similarly among HCW in GIE and NON-GIE (91.7%, CI: 88.6−94.4 vs. 85.8%, CI: 82.4−89.0; p < 0.01) with strongest perceived threats posed by AGPs (90.8%) and close patient contact (70.1%). The very high vaccination rate (100−80%) among physicians was reported at 83.5%, being significantly more frequently reported than among nurses (56.4%, p < 0.01). GIE had more often stated very high vaccination rate compared with NON-GIE (76.1% vs. 65.3%, p < 0.01). A significantly higher rate of GIE was reported to have fewer concerns regarding infection risk after vaccination than NON-GIE (92.0% vs. 80.3%, p < 0.01).

Hospital-wide SARS-CoV-2 antibody screening of 4840 staff members in a University Medical Center in France: a cross-sectional study

OBJECTIVES

Healthcare workers are more likely to be infected by SARS-CoV-2. In order to assess the infectious risk associated with working in a hospital, we sought to estimate the proportion of healthcare professionals infected with SARS-CoV-2 by screening staff in a University Medical Center in France.

SETTING

A hospital-wide screening campaign (comprising a serological test and a questionnaire) ran from 18 May to 26 July 2020.

PRIMARY AND SECONDARY OUTCOME MEASURES

The seroprevalence rate was analysed in a multivariate analysis according to sociodemographic variables (age, sex and profession), exposure to SARS-CoV-2 and symptoms.

RESULTS

A total of 4840 professionals were included, corresponding to 74.5% of the centre's staff. The seroprevalence rate (95% CI) was 9.7% (7.0% to 12.4%). Contact with a confirmed case of COVID-19 was significantly associated with seropositivity (OR (95% CI: 1.43, (1.15 to 1.78)). The seroprevalence rate was significantly higher among nursing assistants (17.6%) than among other healthcare professionals. The following symptoms were predictive of COVID-19: anosmia (OR (95% CI): 1.55, (1.49 to 1.62)), ageusia (1.21, (1.16 to 1.27)), fever (1.15, (1.12 to 1.18)), myalgia (1.03, (1.01 to 1.06)) and headache (1.03, (1.01 to 1.04)).

Detection of Neutralizing Antibodies against SARS-CoV-2 Post-Vaccination in Health Care Workers of a Large Tertiary Hospital in Spain by Using a Rapid Test LFIC and sVNT-ELISA

The presence of neutralizing antibodies (NAbs) against SARS-CoV-2 represent a surrogate marker of immunologic protection in populations at high risk of infection such as healthcare workers caring for hospitalized patients with COVID-19. As recommended by CDC and the European CDC, the use of rapid diagnostic tests during population-based evaluations offers an opportunity to identify individuals with serologic evidence of natural infection or who have undergone vaccination. We carried out a cross-sectional study to assess the presence of neutralizing antibodies against SARS-CoV-2 among medical providers at an intensive care unit of a large referral hospital in Alicante, Spain. In addition, we tested for the presence of neutralizing antibodies compared to serum of uninfected individuals from a Biobank. We were also interested in evaluating the use of a rapid lateral flow immunochromatography (LFIC) test against a surrogate ELISA viral neutralization test (sVNT). This rapid test demonstrated a specificity of 1.000 95% CI (0.91–1.00) and the sensitivity of 0.987 95% CI (0.93–1.00). The negative predictive value was 95%. After six months, this rapid test demonstrated that those immunized with two doses of BioNTech/Pfizer vaccine, maintained optimal levels of neutralizing antibodies. We concluded that all Health Care Workers develop NAbs and the use of this rapid immunochromatographic test represents a potential tool to be used in population-based studies to detect serological antibody responses to vaccination. Vaccination policies could benefit from this tool to assess additional doses of vaccine or boosters among high-risk populations.

SARS-CoV-2 Seroprevalence Among Health Care Workers in Major Private and Public Hospitals With COVID-19 Patient's Referral in Tehran, Iran

Estimating the prevalence of SARS-CoV-2 antibody seropositivity among health care workers (HCWs) is crucial. In this study, the seroprevalence of anti-SARS-CoV-2 antibodies among HCWs of five hospitals of Tehran, Iran with high COVID-19 patient's referrals from April to June, 2020, was assessed. In this cross-sectional study, HCWs from three public and two private hospitals, selected randomly as a pilot, were included. Participants were asked questions on their demographic characteristics, medical history, hospital role, and usage of personal protective equipment (PPE). Iran FDA-approved SARS-CoV-2 ELISA kits were used to detect IgG and IgM antibodies in blood samples. The seroprevalence was estimated on the basis of ELISA test results and adjusted for test performance. Among the 2,065 participants, 1,825 (88.4%) and 240 (11.6%) HCWs were recruited from public and private hospitals, respectively. A total of 340 HCWs were tested positive for SARS-CoV-2-specific IgG or IgM antibodies, and 17.9% of seropositive individuals were asymptomatic. The overall test performance-adjusted seroprevalence estimate among HCWs was 22.6 (95% CI: 20.2–25.1), and PPE usage was significantly higher among HCWs of public vs. private hospitals (66.5 vs. 20.0%). This study found that seroprevalence of SARS-CoV-2 among HCWs was higher in private hospitals (37.0%; 95% CI: 28.6–46.2) than public hospitals (20.7%; 95% CI: 18.2–23.3), and also highest among assistant nurses and nurses, and lowest among janitor or superintendent categories. The PPE usage was especially suboptimal among HCWs in private hospitals. Continued effort in access to adequate PPE and regular screening of hospital staff for detecting asymptomatic personnel, especially during the upcoming wave of infection, are warranted.

ACE2 Serum Levels as Predictor of Infectability and Outcome in COVID-19

Background

COVID‐19 can generate a broad spectrum of severity and symptoms. Many studies analysed the determinants of severity but not among some types of symptoms. More importantly, very few studies analysed patients highly exposed to the virus that nonetheless remain uninfected.

Methods

We analysed serum levels of ACE2, Angiotensin II and anti-Spike antibodies in 2 different cohorts at high risk of viral exposure, highly exposed but uninfected subjects, either high risk health care workers or persons cohabiting with infected close relatives and seropositive patients with symptoms. We tested the ability of the sera of these subjects to neutralize lentivirus pseudotyped with the Spike-protein.

Results

We found that the serum levels of ACE2 are significantly higher in highly exposed but uninfected subjects. Moreover, sera from this seronegative persons can neutralize SARS-CoV-2 infection in cellular assays more strongly that sera from non-exposed negative controls eventhough they do not have anti-CoV-2 IgG antibodies suggesting that high levels of ACE2 in serum may somewhat protect against an active infection without generating a conventional antibody response. Finally, we show that among patients with symptoms, ACE2 levels were significantly higher in infected patients who developed cutaneous as compared with respiratory symptoms and ACE2 was also higher in those with milder symptoms.

Conclusions

These findings suggest that soluble ACE2 could be used as a potential biomarker to predict SARS-CoV-2 infection risk and to discriminate COVID-19 disease subtypes.

Cumulative incidence of SARS-CoV-2 and associated risk factors among healthcare workers: a cross-sectional study in the Eastern Cape, South Africa

OBJECTIVES

This study assesses the cumulative incidence of SARS-CoV-2 infection among healthcare workers (HCWs) during South Africa's first wave and examines the associated demographic, health-related and occupational risk factors for infection.

METHODS

Multistage cluster sampling was used in a cross-sectional study to recruit 1309 HCWs from two academic hospitals in the Eastern Cape, South Africa over 6 weeks in November and December 2020. Prior test results for SARS-CoV-2 PCR and participants' characteristics were recorded while a blood sample was drawn for detection of IgG antibodies against SARS-CoV-2 nucleocapsid protein. The primary outcome measure was the SARS-CoV-2 cumulative incidence rate, defined as the combined total of positive results for either PCR or IgG antibodies, divided by the total sample. The secondary outcome was significant risk factors associated with infection.

RESULTS

Of the total participants included in the analysis (n=1295), the majority were women (81.5%), of black race (78.7%) and nurses (44.8%). A total of 390 (30.1%) HCWs had a positive SARS-CoV-2 PCR result and SARS-CoV-2 antibodies were detected in 488 (37.7%), yielding a cumulative incidence of 47.2% (n=611). In the adjusted logistic regression model, being overweight (adjusted OR (aOR)=2.15, 95% CI 1.44 to 3.20), obese (aOR=1.37, 95% CI 1.02 to 1.85) and living with HIV (aOR=1.78, 95% CI 1.38 to 2.08) were independently associated with SARS-CoV-2 infection. There was no significant difference in infection rates between high, medium and low COVID-19 exposure working environments.

CONCLUSIONS

The high SARS-CoV-2 cumulative incidence in the cohort was surprising this early in the epidemic and probably related to exposure both in and outside the hospitals. To mitigate the impact of SARS-CoV-2 among HCWs, infection prevention and control strategies should target community transmission in addition to screening for HIV and metabolic conditions.

Incidence and prevalence of COVID-19 within a healthcare worker cohort during the first year of the SARS-CoV-2 pandemic

BACKGROUND

Preventing SARS-CoV2 infections in healthcare workers (HCWs) is critical for healthcare delivery. We aimed to estimate and characterize the prevalence and incidence of COVID-19 in a US HCW cohort and to identify risk factors associated with infection.

METHODS

We conducted a longitudinal cohort study of HCWs at 3 Bay Area medical centers using serial surveys and SARS-CoV-2 viral and orthogonal serological testing, including measurement of neutralizing antibodies. We estimated baseline prevalence and cumulative incidence of COVID-19. We performed multivariable Cox proportional hazards models to estimate associations of baseline factors with incident infections and evaluated the impact of time-varying exposures on time to COVID-19 using marginal structural models.

RESULTS

2435 HCWs contributed 768 person years of follow-up time. We identified 21/2435 individuals with prevalent infection, resulting in a baseline prevalence of 0.86% (95% CI, 0.53% to 1.32%). We identified 70/2414 (2.9%) incident infections yielding a cumulative incidence rate of 9.11 cases per 100 person years (95% CI 7.11 to 11.52). Community contact with a known COVID-19 case most strongly correlated with increased hazard for infection (HR 8.1, 95% CI, 3.8, 17.5). High-risk work-related exposures (i.e., breach in protective measures) drove an association between work exposure and infection (HR 2.5, 95% CI, 1.3-4.8). More cases were identified in HCW when community case rates were high.

CONCLUSION

We observed modest COVID-19 incidence despite consistent exposure at work. Community contact was strongly associated with infections but contact at work was not unless accompanied by high-risk exposure.

SARS-CoV-2 Reverse Transcription-Polymerase Chain Reaction Positivity and Seroprevalence among Health Care Workers in a Referral Cancer Institute: A Cross-sectional Study

BACKGROUND: During the ongoing coronavirus disease 2019 pandemic, healthcare workers (HCWs) are presumed to be at increased risk of infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), transmitting the infection to vulnerable patients if they are not timeously isolated. AIM: This study aimed to determine the point prevalence of SARS-CoV-2 infection in a cohort of HCWs providing oncology services. METHODS AND RESULTS: HCWs in a large referral cancer hospital in Egypt were tested using real-time reverse transcription-polymerase chain reaction (RT-PCR) on nasopharyngeal swabs, and immunochromatography-based rapid serological test (RST). Clinical and epidemiological data were collected. In 2020, 999 HCWs were screened, of whom 86 tested positive for SARS-CoV-2 by RT-PCR (8.6%) and 127 subjects were seropositive for antibodies against SARS-CoV-2 by RST (12.8%). Immunoglobulin M seroprevalence demonstrated considerable concordance with RT-PCR positivity (sensitivity 82.14% and specificity 96.71%). Most HCWs (>95%) reported adherence to personal protective equipment. Patient transporters/cleaner were the group with the highest frequency of positive RT-PCR (19%) whereas laboratory and radiology technicians displayed the lowest frequency. Fever, dry cough, rhinorrhea, shortness of breath, fatigue and diarrhea were significantly associated with RT-PCR positivity, with increased likelihood of being positive with the presence of five or six simultaneous symptoms. CONCLUSIONS: The point prevalence of SARS-CoV-2 infection in screened HCWs is 8.6% by RT-PCR and seroprevalence is 12.8% by RST. Strict measures should be implemented to minimize transmission within healthcare settings and to the community. Our data support the importance of HCWs screening for SARS-CoV-2, taking in account the significant proportion of asymptomatic carriers.

The Experiences of Nurses of Infectious and Non- Infectious Wards of Caring COVID-19 Patients in a Big Hospital in Iran: A Qualitative Study

Background

Nurses play a very important role in caring for patients with coronavirus disease-19 (COVID-19). They are on the frontline fighting COVID-19. The objective was to explore the experiences of nurses in the surgical and infectious wards about caring for patients with COVID-19 in a large and tertiary care hospital in Iran.

Materials and Methods

This was a qualitative study. Semi-structured qualitative interviews were conducted with 18 nurses in the Imam Reza Hospital Complex from April to May 2020, Mashhad, Iran. Data analysis was performed using the method proposed by Lundman and Granheim. The Maxqda10 software was used.

Results

The experiences were summarized into three categories: (1) experiencing new feelings and relationships with colleagues and patients, (2) viewpoints about managers' performance, and (3) concern about getting infected with COVID-19. Findings reflected similar experiences on personal protective equipment between nurses in the surgical and infectious wards. Experiencing new feelings and relationships with colleagues and patients and concern about getting infected and spreading the COVID-19 were mostly expressed by infectious nurses and surgical nurses, respectively.

Conclusions

This research results provide evidence of the experiences of infectious and non-infectious disease nurses who are currently caring for COVID-19 patients. Due to some differences between the experiences of these two groups in COVID-19, it is suggested to pay more attention to the needs and required skills in the staff mix during a crisis.

A cross sectional study found differential risks for COVID-19 seropositivity amongst health care professionals in Chile

Objective

Health care workers (HCWs) are at increased risk for SARS-CoV-2 infection, however not all face the same risk. We aimed to determine IgG/IgM prevalence and risk factors associated with seropositivity in Chilean HCWs.

Study Design and Setting

This was a nationwide, cross-sectional study including a questionnaire and COVID-19 lateral flow IgG/IgM antibody testing. All HCWs in the Chilean public health care system were invited to participate following the country's first wave.

Results

IgG/IgM positivity in 85,529 HCWs was 7.2%, ranging from 1.6% to 12.4% between regions. Additionally, 9.7% HCWs reported a positive PCR of which 47% were seropositive. Overall, 10,863 (12.7%) HCWs were PCR and/or IgG/IgM positive. Factors independently associated with increased odds ratios (ORs) for seropositivity were: working in a hospital, night shifts, contact with Covid-19, using public transport, male gender, age>45, BMI ≥30, and reporting ≥2 symptoms. Stress and/or mental health disorder and smoking were associated with decreased ORs. These factors remained significant when including PCR positive cases in the model.

Conclusions

HCWs in the hospital were at highest risk for COVID-19, and several independent risk factors for seropositivity and/or PCR positivity were identified.

Experiences of nurses diagnosed with COVID-19 in Turkey: A qualitative study

AIMS

This study examined the experiences of nurses diagnosed with COVID-19 under the guidance of Meleis' Transitions Theory.

BACKGROUND

Nurses, who make up the majority of healthcare professionals, are struggling with COVID-19, a silent war, on the front lines at the cost of their lives. The pandemic has deeply affected nurses' lives, and hundreds of nurses around the world have been diagnosed with COVID-19 and died.

METHODS

A descriptive qualitative approach was used in this study. Data were collected from 18 nurses who experienced COVID-19 symptoms, with a semistructured interview form prepared based on Meleis' Transitions Theory concepts. Interview transcripts were analyzed using a thematic analysis technique. The Consolidated Criteria for Reporting Qualitative Research checklist was used in the study.

RESULTS

The six themes that emerged in the data analysis were emotions experienced when nurses tested positive for COVID-19, emotions experienced during the quarantine process, posttraumatic growth, methods of coping with COVID-19, nursing care after COVID-19 treatment, and metaphors about COVID-19.

CONCLUSION

This study showed that being diagnosed with COVID-19 caused nurses to have both positive (posttraumatic growth, empathic and psychosocial nursing care) and negative experiences (fear of death, stigma, etc.). They tried to cope with adverse situations due to COVID-19 by obtaining social support, thinking positively, and engaging in domestic activities.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

To reduce COVID-19-related physical and psychological symptoms, appropriate policies should be developed for effective and rapid nursing workforce planning, extending the time allocated for postdiagnosis treatment, updating infection control and prevention guides, training nurses, and providing ongoing psychosocial counseling services that nurses can access.

Dynamics of spreading of SARS-CoV-2 in a Belgian hemodialysis facility: The importance of the analysis of viral strains

In‐center maintenance hemodialysis (HD) patients are at high risk of acquiring coronavirus disease 2019 (COVID‐19) by cross‐contamination inside the unit. The aim of this study was to assess retrospectively the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) transmission during the very first pandemic phase (March–July 2020) in a cohort of in‐center maintenance HD patients and in nurses the same HD facility, using a phylogenetic approach. All SARS‐CoV‐2 quantitative reverse‐transcription polymerase chain reaction positive patients and nurses from our HD unit‐respectively 10 out of 98, and 8 out of 58‐ and two other positive patients dialyzed in our self‐care unit were included. Whole‐genome viral sequencing and phylogenetic analysis supported the cluster investigation. Five positive patients were usually dialyzed in the same room and same shift before their COVID‐19 diagnosis was made. Viral sequencing performed on 4/5 patients' swabs showed no phylogenetic link between their viruses. The fifth patient (whose virus could not be sequenced) was dialyzed at the end of the dialysis room and was treated by a different nurse than the one in charge of the other patients. Three nurses shared the same virus detected in both self‐care patients (one of them had been transferred to our in‐center facility). The epidemiologically strongly suspected intra‐unit cluster could be ruled out by viral genome sequencing. The infection control policy did not allow inter‐patient contamination within the HD facility, in contrast to evidence of moderate dissemination within the nursing staff and in the satellite unit. Epidemiologic data without phylogenetic confirmation might mislead the interpretation of the dynamics of viral spreading within congregate settings.

In‐center maintenance hemodialysis (HD) patients are at high risk of acquiring coronavirus disease 2019 by cross‐contamination inside the unit. In this study we assessed the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) transmission in a cohort of in‐center maintenance hemodialysis patients and in nurses the same HD facility in Brussels, Belgium, using whole‐genome viral sequencing and phylogenetic analysis.

All SARS‐CoV‐2 quantitative reverse‐transcription polymerase chain reaction (RT‐qPCR) positive patients (10 out 98) and nurses from our HD unit (8 out 58) and two other positive patients dialyzed in our self‐care unit were included. An intra‐unit cluster was suspected because five SARS‐CoV‐2 RT‐qPCR positive patients were dialyzed in the same room at the same time three times weekly.

The epidemiologically strongly suspected intra‐unit cluster could be ruled out by viral genome sequencing. In contrast, three nurses shared the same virus detected in both self‐care patients (one of them had been transferred to our in‐center facility).

Epidemiologic data without phylogenetic confirmation might mislead the interpretation of the dynamics of viral spreading within congregate settings.

The seroprevalence of SARS-CoV-2 during the first wave in Europe 2020: A systematic review

BACKGROUND

A year following the onset of the COVID-19 pandemic, new infections and deaths continue to increase in Europe. Serological studies, through providing evidence of past infection, can aid understanding of the population dynamics of SARS-CoV-2 infection.

OBJECTIVES

This systematic review of SARS-CoV-2 seroprevalence studies in Europe was undertaken to inform public health strategies including vaccination, that aim to accelerate population immunity.

METHODS

We searched the databases Web of Science, MEDLINE, EMBASE, SCOPUS, Cochrane Database of Systematic Reviews and grey literature sources for studies reporting seroprevalence of SARS-CoV-2 antibodies in Europe published between 01/12/2019-30/09/20. We provide a narrative synthesis of included studies. Studies were categorized into subgroups including healthcare workers (HCWs), community, outbreaks, pregnancy and children/school. Due to heterogeneity in other subgroups, we only performed a random effects meta-analysis of the seroprevalence amongst HCWs stratified by their country.

RESULTS

115 studies were included spanning 17 European countries, that estimated the seroprevalence of SARS-CoV-2 from samples obtained between November 2019 -August 2020. A total of 54/115 studies included HCWs with a reported seroprevalence among HCWs ranging from 0.7% to 45.3%, which did not differ significantly by country. In community studies significant heterogeneity was reported in the seroprevalence between different age groups and the majority of studies reported there was no significant difference by gender.

CONCLUSION

This review demonstrates a wide heterogeneity in reported seroprevalence of SARS-CoV-2 antibodies between populations. Continued evaluation of seroprevalence is required to understand the impact of public health measures and inform interventions including vaccination programmes.

Occupational Health of Frontline Healthcare Workers in the United Arab Emirates during the COVID-19 Pandemic: A Snapshot of Summer 2020

The study aim was to understand the availability of personal protective equipment (PPE) and the levels of anxiety, depression, and burnout of healthcare workers (HCWs) in the United Arab Emirates (UAE). This study was an online-based, cross-sectional survey during July and August 2020. Participants were eligible from the entire country, and 1290 agreed to participate. The majority of HCWs were females aged 30-39 years old, working as nurses, and 80% considered PPE to be available. Twelve percent of respondents tested positive for SARS-CoV-2. Half of HCWs considered themselves physically tired (52.2%), reported musculoskeletal pain or discomfort (54.2%), and perceived moderate-to-high levels of burnout on at least one of three burnout domains (52.8%). A quarter of HCWs reported anxiety (26.3%) or depression (28.1%). HCWs reporting not having musculoskeletal pain, having performed physical activity, and higher scores of available PPE reported lower scores of anxiety, depression, and burnout. UAE HCWs experienced more access to PPE and less anxiety, depression, and burnout compared with HCWs in other countries. Study findings can be used by healthcare organizations and policymakers to ensure adequate measures are implemented to maximize the health and wellbeing of HCWs during the current COVID-19 and future pandemics.

Systematic review of productivity loss among healthcare workers due to Covid-19

Objective

To assess existing evidence on the effects of COVID‐19 on healthcare workers (HCWs) using the health‐related productivity loss approach.

Methods

A systematic search of online databases including PubMed, Scopus, Ovid, Web of Science, and EMBASE was conducted up to 25 August 2020. Following two screening stages, studies related to the effects of COVID‐19 on healthcare workers were included in the study.

Results

82 studies were included in the analysis. The COVID‐19 related death rate among HCWs ranged from 0.00‐0.7%, while the positive test incidence varied between 0.00 and 24.4%. 39 evidences assessed psychological disorders. A wide range of psychological disorders observed among HCWs: 5.2 to 71.2% in anxiety, 1.00 to 88.3% in stress, 8.27 to 61.67% in insomnia, and 4.5 to 50.4% in depression.

Conclusions

The early evidence suggests that healthcare workers are one of the most vulnerable groups when it comes to positive COVID‐19 infection, mortality, and mental illness.

Neutralizing antibody responses following natural SARS-CoV-2 infection: Dynamics and correlation with commercial serologic tests

The prediction of SARS-CoV-2 immunity by commercially available serologic tests will be crucial to assess the efficacy of vaccination. We used plaque reduction neutralization testing as the reference standard to evaluate the diagnostic performance of six commercial serologic tests for monitoring SARS-CoV-2 neutralizing antibodies. Euroimmun ELISA anti-spike 1 IgG, Euroimmun anti-spike 1 IgG QuantiVac ELISA, Elecsys Anti-nucleocapsid protein total antibodies, Elecsys Anti-receptor-binding domain total antibodies, VIDAS anti-spike subdomain IgG, and Microblot-Array COVID-19 IgG assay were performed on 228 sera from 89 healthcare workers who participated in a six-month seroprevalence survey. Although all immunoassays demonstrated similar performances, VIDAS SARS-CoV-2 IgG and Euroimmun QuantiVac IgG (area under the curve 0.96 and 0.95 respectively) showed the better ability to detect Nabs. Except for the Elecsys Anti-SARS-CoV-2 and the Elecsys Anti-SARS-CoV-2 S assays, the commercial serologic tests evaluated here showed a significant decrease of antibody titers in the 6-month follow-up samples. Depending on the immunoassay, 21% to 33% of the participants became seronegative, and 16.9% had a loss of neutralizing antibodies. Microblot-Array assay results showed cross-reactivity with HCoVNL63 in only one sample, and this sample showed SARS-CoV-2 neutralizing capacity. In conclusion, our results support the use of VIDAS SARS-CoV-2 IgG, Euroimmun Anti-SARS-CoV-2 ELISA IgG, Euroimmun Anti-SARS-CoV-2 QuantiVac ELISA IgG and Microblot-Array COVID-19 IgG assays to monitor neutralizing antibody response following natural SARS-CoV-2 infection. These immunoassays could facilitate the prediction of post-vaccine protection in the long term and the allocation of booster doses.

Low SARS-CoV-2 seroprevalence but high perception of risk among healthcare workers at children's hospital before second pandemic wave in Germany

BACKGROUND

Healthcare workers are considered a particularly high-risk group during the coronavirus disease 2019 (COVID-19) pandemic. Healthcare workers in paediatrics are a unique subgroup: they come into frequent contact with children, who often experience few or no symptoms when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and, therefore, may transmit the disease to unprotected staff. In Germany, no studies exist evaluating the risk of COVID-19 to healthcare workers in paediatric institutions.

METHODS

We tested the staff at a large children's hospital in Germany for immunoglobulin (Ig) G antibodies against the nucleocapsid protein of SARS-CoV-2 in a period between the first and second epidemic wave in Germany. We used a questionnaire to assess each individual's exposure risk and his/her own perception of having already been infected with SARS-CoV-2.

RESULTS

We recruited 619 participants from all sectors, clinical and non-clinical, constituting 70% of the entire staff. The seroprevalence of SARS-CoV-2 antibodies was 0.325% (95% confidence interval 0.039-1.168). Self-perceived risk of a previous SARS-CoV-2 infection decreased with age (odds ratio, 0.81; 95% confidence interval, 0.70-0.93). Having experienced symptoms more than doubled the odds of a high self-perceived risk (odds ratio, 2.18; 95% confidence interval, 1.59-3.00). There was no significant difference in self-perceived risk between men and women.

CONCLUSIONS

Seroprevalence was low among healthcare workers at a large children's hospital in Germany before the second epidemic wave, and it was far from a level that confers herd immunity. Self-perceived risk of infection is often overestimated.

Sero-prevalence of anti-SARS-CoV-2 antibodies among healthcare workers: A multicenter study from Egypt

Background

Healthcare workers (HCWs) are at a high risk for disease exposure. Given the limited availability of nucleic acid testing by PCR in low resource settings, serological assays can provide useful data on the proportion of HCWs who have recently or previously been infected. Therefore, in this study, we conducted an immunologic study to determine the seroprevalence of anti-SARS-CoV-2 antibodies in two university hospitals in Egypt.

Methods

in this cross sectional study, HCWs who were working in SARS-CoV-2 Isolation Hospitals were interviewed. Estimating specific antibodies (IgM and IgG) against SARS-CoV-2 was carried out using an enzyme-linked immunosorbent assay targeting the Spike antigen of SARS-CoV-2 virus.

Results

Out of 111, 82 (74%) HCWs accepted to participate with a mean age of 31.5 ± 8.5 years. Anti-SARS-COV2 antibodies were detected in 38/82 (46.3%) of cases with a mean age of 31 years and female HCWs constituted 57.6% of cases. The highest rate of seropositivity was from the nurses (60.5%), and physicians (31.6%) with only (7.9%) technicians. Only 28/82 (34.1%) HCWs reported previous history of COVID19. We reported a statistically significant difference in the timing of exposure (p = 0.010) and the frequency of contact with COVID-19 cases (p = 0.040) between previously infected and on-infected HCWs. Longer time of recovery was reported from IgG positive HCWs (p = 0.036).

Conclusion

The high frequency of seropositive HCWs in investigated hospitals is alarming, especially among asymptomatic personnel. Confirmation of diseased HCWs (among seropositive ones) are warranted.

Rapid and Laboratory SARS-CoV-2 Antibody Testing in High-Risk Hospital Associated Cohorts of Unknown COVID-19 Exposure, a Validation and Epidemiological Study After the First Wave of the Pandemic

Objective: We aimed to use SARS-CoV-2 antibody tests to assess the asymptomatic seroprevalence of individuals in high-risk hospital cohorts who's previous COVID-19 exposure is unknown; staff, and patients requiring haemodialysis or chemotherapy after the first wave.

Methods: In a single Center, study participants had five SARS-CoV-2 antibody tests done simultaneously; one rapid diagnostic test (RDT) (Superbio Colloidal Gold IgM/IgG), and four laboratory tests (Roche Elecsys® Anti-SARS-CoV-2 IgG [RE], Abbott Architect i2000SR IgG [AAr], Abbott Alinity IgG [AAl], and Abbott Architect IgM CMIA). To determine seroprevalence, only positive test results on laboratory assay were considered true positives.

Results: There were 157 participants, of whom 103 (65.6%) were female with a median age of 50 years (range 19–90). The IgG component of the RDT showed a high number of false positives (n = 18), was inferior to the laboratory assays (p < 0.001 RDT vs. AAl/AAr, p < 0.001 RDT vs. RE), and had reduced specificity (85.5% vs. AAl/AAr, 87.2% vs. RE). Sero-concordance was 97.5% between IgG laboratory assays (RE vs. AAl/AAr). Specificity of the IgM component of the RDT compared to Abbott IgM CMIA was 95.4%. Ten participants had positivity in at least one laboratory assay, seven (9.9%) of which were seen in HCWs. Two (4.1%) hematology/oncology (H/O) patients and a single (2.7%) haemodialysis (HD) were asymptomatically seropositive. Asymptomatic seroprevalence of HCWs compared to patients was not significant (p = 0.105).

Conclusion: HCWs (9.9%) had higher, although non-significant asymptomatic seroprevalence of SARS-CoV-2 antibodies compared to high-risk patients (H/O 4.1%, HD 2.7%). An IgM/IgG rapid diagnostic test was inferior to laboratory assays. Sero-concordance of 97.5% was found between IgG laboratory assays, RE vs. AAl/AAr.

Serological assessment of SARS-CoV-2 infection during the first wave of the pandemic in Louisville Kentucky

Serological assays intended for diagnosis, sero-epidemiologic assessment, and measurement of protective antibody titers upon infection or vaccination are essential for managing the SARS-CoV-2 pandemic. Serological assays measuring the antibody responses against SARS-CoV-2 antigens are readily available. However, some lack appropriate characteristics to accurately measure SARS-CoV-2 antibodies titers and neutralization. We developed an Enzyme-linked Immunosorbent Assay (ELISA) methods for measuring IgG, IgA, and IgM responses to SARS-CoV-2, Spike (S), receptor binding domain (RBD), and nucleocapsid (N) proteins. Performance characteristics of sensitivity and specificity have been defined. ELISA results show positive correlation with microneutralization and Plaque Reduction Neutralization assays with infectious SARS-CoV-2. Our ELISA was used to screen healthcare workers in Louisville, KY during the first wave of the local pandemic in the months of May and July 2020. We found a seropositive rate of approximately 1.4% and 2.3%, respectively. Our analyses demonstrate a broad immune response among individuals and suggest some non-RBD specific S IgG and IgA antibodies neutralize SARS-CoV-2.

Exposure to SARS-CoV-2 in Hospital Environment: Working in a COVID-19 Ward Is a Risk Factor for Infection

Aims. Health care workers (HCWs) are at risk of acquiring the Severe Acute Respiratory Syndrome Coronavirus 2 Infection (SARS-CoV-2). The aim of the study is to determine the SARS-CoV-2 positivity rates during the first epidemiologic peak among HCWs of a south Belgian hospital and to identify risks factors for infection. Methods. All hospital staff who worked during the first epidemiological peak were asked to answer a questionnaire regarding demographical data, function, type of working unit, type of contact with patients, eventual symptomatology, and the positivity of reverse transcription-polymerase chain reaction (RT-PCR) testing or immunoassay. Results. A total of 235 questionnaires were collected; 90 (38%) HCWs tested positive for SARS-CoV-2 from either RT-PCR or immunoassay testing. The positivity rate of HCWs between wards was statistically different (p = 0.004) and was higher in COVID-19 wards than Intensive Care Unit (ICU) and Emergency Department (ED). A total of 114 (49%) HCWs presented SARS-CoV-2-compatible symptomatology; 79 (88%) were positive on either RT-PCR or immunoassay testing; 74 (37%) HCWs were unable to work during the studied period; 5 were hospitalized. No deaths were reported. Multivariate logistic regression modeling showed that having symptoms was highly associated with test positivity (OR 23.3, CI 11.1, 53.1, p-value < 0.001). Working in a COVID-19 ward against working in ICU or ED was also predictive of positivity among HCWs (OR 3.25, CI 1.50, 7.28, p-value = 0.003). Discussion and Conclusions. This study shows a higher positivity rate compared to already reported positivity rates among HCWs. Reported differences in positivity rates depend on many factors, such as local crisis intensity, screening strategy, training in use of self-protective equipment, and study selection bias. HCWs working in COVID-19 wards, in comparison to ED and ICU, seemed at greater risk of being infected in this study. This could be explained by the disparity of HCWs' experience in handling self-protective equipment and knowledge in infection prevention. Hence, care should be taken in proper training for less-experienced HCWs during hospital epidemics. The latter could increase HCWs' protection and consequently decrease work absenteeism, ensuring enhanced continuity of patient care during hospital crisis. Rapid quarantine of symptomatic HCWs could reduce contamination rates, as having symptoms was highly associated with test positivity in this study.

Association between SARS-CoV-2 exposure and antibody status among healthcare workers in two London hospitals: a cross-sectional study

BACKGROUND

Patient-facing (frontline) health-care workers (HCWs) are at high risk of repeated exposure to SARS-CoV-2.

AIM

We sought to determine the association between levels of frontline exposure and likelihood of SARS-CoV-2 seropositivity amongst HCW.

METHODS

A cross-sectional study was undertaken using purposefully collected data from HCWs at two hospitals in London, United Kingdom (UK) over eight weeks in May-June 2020. Information on sociodemographic, clinical and occupational characteristics was collected using an anonymised questionnaire. Serology was performed using split SARS-CoV-2 IgM/IgG lateral flow immunoassays. Exposure risk was categorised into five pre-defined ordered grades. Multivariable logistic regression was used to examine the association between being frontline and SARS-CoV-2 seropositivity after controlling for other risks of infection.

FINDINGS

615 HCWs participated in the study. 250/615 (40.7%) were SARS-CoV-2 IgM and/or IgG positive. After controlling for other exposures, there was non-significant evidence of a modest association between being a frontline HCW (any level) and SARS-CoV-2 seropositivity compared to non-frontline status (OR 1.39, 95% CI 0.84-2.30, P=0.200). There was 15% increase in the odds of SARS-CoV-2 seropositivity for each step along the frontline exposure gradient (OR 1.15, 95% CI 1.00-1.32, P=0.043).

CONCLUSION

We found a high SARS-CoV-2 IgM/IgG seropositivity with modest evidence for a dose-response association between increasing levels of frontline exposure risk and seropositivity. Even in well-resourced hospital settings, appropriate use of personal protective equipment, in addition to other transmission-based precautions for inpatient care of SARS-CoV-2 patients could reduce the risk of hospital-acquired SARS-CoV-2 infection among frontline HCW.

Analyzing the Impact of COVID-19 Trauma on Developing Post-Traumatic Stress Disorder among Emergency Medical Workers in Spain

The early stages of the COVID-19 pandemic presented the characteristics of a traumatic event that could trigger post-traumatic stress disorder. Emergency Medical Services workers are already a high-risk group due to their professional development. The research project aimed to analyse the impact of the COVID-19 pandemic on EMS professionals in terms of their mental health. For this purpose, we present a descriptive crosssectional study with survey methodology. A total of 317 EMS workers (doctors, nurses, and emergency medical technicians) were recruited voluntarily. Psychological distress, post-traumatic stress disorder, and insomnia were assessed. The instruments were the General Health Questionnaire-12 (GHQ-12), the Davidson Trauma Scale (DTS-8), and the Athens Insomnia Scale (AIS-8). We found that 36% of respondents had psychological distress, 30.9% potentially had PTSD, and 60.9% experienced insomnia. Years of work experience were found to be positively correlated, albeit with low effect, with the PTSD score (r = 0.133). Finally, it can be stated that the COVID-19 pandemic has been a traumatic event for EMS workers. The number of professionals presenting psychological distress, possible PTSD, or insomnia increased dramatically during the early phases of the pandemic. This study highlights the need for mental health disorder prevention programmes for EMS workers in the face of a pandemic.

Asymptomatic SARS-CoV-2 infection: A systematic review and meta-analysis

Quantification of asymptomatic infections is fundamental for effective public health responses to the COVID-19 pandemic. Discrepancies regarding the extent of asymptomaticity have arisen from inconsistent terminology as well as conflation of index and secondary cases which biases toward lower asymptomaticity. We searched PubMed, Embase, Web of Science, and World Health Organization Global Research Database on COVID-19 between January 1, 2020 and April 2, 2021 to identify studies that reported silent infections at the time of testing, whether presymptomatic or asymptomatic. Index cases were removed to minimize representational bias that would result in overestimation of symptomaticity. By analyzing over 350 studies, we estimate that the percentage of infections that never developed clinical symptoms, and thus were truly asymptomatic, was 35.1% (95% CI: 30.7 to 39.9%). At the time of testing, 42.8% (95% prediction interval: 5.2 to 91.1%) of cases exhibited no symptoms, a group comprising both asymptomatic and presymptomatic infections. Asymptomaticity was significantly lower among the elderly, at 19.7% (95% CI: 12.7 to 29.4%) compared with children at 46.7% (95% CI: 32.0 to 62.0%). We also found that cases with comorbidities had significantly lower asymptomaticity compared to cases with no underlying medical conditions. Without proactive policies to detect asymptomatic infections, such as rapid contact tracing, prolonged efforts for pandemic control may be needed even in the presence of vaccination.

Healthcare Workers Infection Rate in the Era of Coronavirus Disease 2019 - in Tertiary Teaching Hospital

BACKGROUND: Healthcare workers (HCWs) are at the frontline defense against coronavirus disease 2019 (COVID-19) pandemic. AIM: The study aimed to describe the characteristics and appraise potential risk factors of COVID-19 transmission among HCWs who tested positive for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in one of Cairo University Hospitals. METHOD: Cross-sectional descriptive analysis of confirmed polymerase chain reaction (PCR) positive versus negative cases for COVID-19. RESULTS: Through March–June 2020, (145/846; 17%) suspected HCWs were tested for COVID-19 by PCR; out of them (70/145; 48.3%) were confirmed as positive, these positive cases represented (70/846; 8.3%) of all HCWs of the hospital. About 33% of confirmed COVID-19 positive HCWs acquired the infection from the healthcare while only (13/70; 19%) from community settings, and no clear exposure data were identified in (34/70; 48%) of cases. Most of symptomatic cases showed a positive PCR test for SARS-CoV-2 versus asymptomatic cases, p < 0.001. There was no statistical significance regarding gender, age, presence of comorbidity, workload or the type of acquisition. CONCLUSION: HCWs are at an increased risk of COVID-19 infection at the workplace. Strict implementation of infection control measures is of crucial role in preventing transmission of COVID-19 infection in health-care settings.

The front-line during the coronavirus disease 2019 pandemic: healthcare personnel

PURPOSE OF REVIEW

An estimated four to 11% of reported coronavirus disease 2019 (COVID-19) cases occurs in healthcare personnel (HCP). HCP are at high risk of acquiring and transmitting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) given their close contact with individuals with recognized and unrecognized COVID-19. We summarize the literature to date describing the epidemiology, identifying risk factors associated with COVID-19, and analyzing clinical characteristics and outcomes of SARS-CoV-2 infection in HCP.

RECENT FINDINGS

The prevalence of SARS-CoV-2 antibodies among HCP ranges from 0.7 to 45%. Although there is heterogeneity in the seroprevalence rate reported in the literature, HCP may be at increased risk of SARS-CoV-2 infection from exposure to patients with COVID-19. The literature supports that this can be minimized with adequate personal protective equipment (PPE) supply, proper hand hygiene, appropriate PPE use, and other infection prevention measures. In addition, infections in HCP are commonly acquired in the community as well as in nonclinical care settings including break rooms or work rooms.

SUMMARY

While much focus has been on minimizing patient-to-HCP transmission of SARS-CoV-2, additional efforts are needed to prevent exposures in nonclinical care settings and in the community.

Effect of Professional and Extra-Professional Exposure on Seroprevalence of SARS-CoV-2 Infection among Healthcare Workers of the French Alps: A Multicentric Cross-Sectional Study

We aimed to report SARS-CoV-2 seroprevalence after the first wave of the pandemic among healthcare workers, and to explore factors associated with an increased infection rate. We conducted a multicentric cross-sectional survey from 27 June to 31 September 2020. For this survey, we enrolled 3454 voluntary healthcare workers across four participating hospitals, of which 83.4% were female, with a median age of 40.6 years old (31.8-50.3). We serologically screened the employees for SARS-CoV-2, estimated the prevalence of infection, and conducted binomial logistic regression with random effect on participating hospitals to investigate associations. We estimated the prevalence of SARS-CoV-2 infection at 5.0% (95 CI, 4.3%-5.8%). We found the lowest prevalence in health professional management support (4.3%) staff. Infections were more frequent in young professionals below 30 years old (aOR = 1.59, (95 CI, 1.06-2.37)), including paramedical students and residents (aOR = 3.38, (95 CI, 1.62-7.05)). In this group, SARS-CoV-2 prevalence was up 16.9%. The location of work and patient-facing role were not associated with increased infections. Employees reporting contacts with COVID-19 patients without adequate protective equipment had a higher rate of infection (aOR = 1.66, (95 CI, 1.12-2.44)). Aerosol-generating tasks were associated with a ~1.7-fold rate of infection, regardless of the uptake of FFP2. Those exposed to clusters of infected colleagues (aOR = 1.77, (95 CI, 1.24-2.53)) or intra-familial COVID-19 relatives (aOR = 2.09, (95 CI, 1.15-3.80)) also had a higher likelihood of infection. This report highlights that a sustained availability of personal protective equipment limits the SARS-CoV-2 infection rate to what is measured in the general population. It also pinpoints the need for dedicated hygiene training among young professionals, justifies the systematic eviction of infected personnel, and stresses the need for interventions to increase vaccination coverage among any healthcare workers.

Prevalence and incidence of anti-SARS-CoV-2 antibodies among healthcare workers in Belgian hospitals before vaccination: a prospective cohort study

OBJECTIVES

To describe prevalence and incidence of anti-SARS-CoV-2 antibodies among Belgian hospital healthcare workers (HCW) in April-December 2020.

DESIGN

Prospective cohort study. Follow-up was originally planned until September and later extended.

SETTING

Multicentre study, 17 hospitals.

PARTICIPANTS

50 HCW were randomly selected per hospital. HCW employed beyond the end of the study and whose profession involved contact with patients were eligible. 850 HCW entered the study in April-May 2020, 673 HCW (79%) attended the September visit and 308 (36%) the December visit.

OUTCOME MEASURES

A semiquantitative ELISA was used to detect IgG against SARS-CoV-2 in serum (Euroimmun) at 10 time points. In seropositive samples, neutralising antibodies were measured using a virus neutralisation test. Real-time reverse transcription PCR (RT-qPCR) was performed to detect SARS-CoV-2 on nasopharyngeal swabs. Participant characteristics and the presence of symptoms were collected via an online questionnaire.

RESULTS

Among all participants, 80% were women, 60% nurses and 21% physicians. Median age was 40 years. The seroprevalence remained relatively stable from April (7.7% (95% CI: 4.8% to 12.1%) to September (8.2% (95% CI: 5.7% to 11.6%)) and increased thereafter, reaching 19.7% (95% CI: 12.0% to 30.6%) in December 2020. 76 of 778 initially seronegative participants seroconverted during the follow-up (incidence: 205/1000 person-years). Among all seropositive individuals, 118/148 (80%) had a positive neutralisation test, 83/147 (56%) presented or reported a positive RT-qPCR, and 130/147 (88%) reported COVID-19-compatible symptoms at least once. However, only 46/73 (63%) of the seroconverters presented COVID-19-compatible symptoms in the month prior to seroconversion.

CONCLUSIONS

The seroprevalence among hospital HCW was slightly higher than that of the general Belgian population but followed a similar evolution, suggesting that infection prevention and control measures were effective and should be strictly maintained. After two SARS-CoV-2 waves, 80% of HCW remained seronegative, justifying their prioritisation in the vaccination strategy.

TRIAL REGISTRATION NUMBER

NCT04373889.

Hesitancy towards COVID-19 Vaccination among Healthcare Workers: A Multi-Centric Survey in France

Vaccination programs against COVID-19 are being scaled up. We aimed to assess the effects of vaccine characteristics on vaccine hesitancy among healthcare workers in a multi-center survey conducted within French healthcare facilities from 1 December 2020 to 26 March 2021. We invited any healthcare workers naïve of COVID-19 vaccination to complete an online self-questionnaire. They reported on their socio-demographic characteristics, as well as their perception and beliefs towards vaccination. We measured their willingness to get vaccinated in eight scenarios for candidates' vaccines presented sequentially (1 to 4-point scale). Candidates' vaccines varied for efficacy (25%, 50%, 100%), length of immunization (1 year or lifetime), frequency (<1/100, <1/10,000), and severity (none, moderate, severe) of adverse events. We analyzed 4349 healthcare workers' responses with interpretable questionnaires. The crude willingness to get vaccinated was 53.2% and increased over time. We clustered the trajectories of responses using an unsupervised classification algorithm (k-means) and identified four groups of healthcare workers: those willing to get vaccinated in any scenario (18%), those not willing to get vaccinated at all (22%), and those hesitating but more likely to accept (32%) or reject (28%) the vaccination depending on the scenario. In these last two subgroups, vaccine acceptance was growing with age, educational background and was higher among men with condition. Compared to an ideal vaccine candidate, a 50% reduced efficacy resulted in an average drop in acceptance by 0.8 (SD ± 0.8, -23.5%), while it was ranging from 1.4 (SD ± 1.0, -38.4%) to 2.1 (SD ± 1.0, -58.4%) in case of severe but rare adverse event. The acceptance of a mandatory immunization program was 29.6% overall and was positively correlated to the willingness to get vaccinated, ranging from 2.4% to 60.0%. Even if healthcare workers represent a heterogeneous population, most (80%) could accept the vaccination against COVID-19. Their willingness to get the vaccine increased over time and as immunization programs became available. Among hesitant professionals, the fear of adverse events was the main concern. Targeted information campaigns reassuring about adverse events may increase vaccine coverage, in a population with a strong opinion about mandatory immunization programs.

Different Laboratory Diagnosis Methods of COVID-19: A Systematic Review

: The virus causing COVID-19 disease is known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease spread rapidly and was transmitted like a contagious disease throughout China, and then it gradually spread in other parts of the world. Accordingly, the rapid and accurate detection of the SARS-CoV-2 virus plays an essential role in selecting timely treatments, saving lives, and preventing the spread of the disease. This study summarizes the methods used to identify coronavirus nucleic acid. The effectiveness of coronavirus nucleic acid detection kits by different samples and the performance of other diagnostic techniques are also addressed in this study. We searched Embase, Google Scholar, MEDLINE, Web of Science, Scopus, and PubMed databases as well as the references of all relevant articles in English published during 2019 - 2020 using keywords related to COVID-19, detection kits, and respiratory failure and proceedings from relevant conferences and congresses. The authors collected the relevant reports, and each of the authors independently reviewed the data published in different studies. The results of previous studies indicated that the diagnosis methods of the COVID-19 disease are the RT-PCR method, ELISA kits, quick tests, white blood cell count, C-reactive protein (CRP) levels, other laboratory factors and antigenic detection methods. Given the sensitivity and specificity of these methods at different periods using different samples, the disease interpretation can be performed accurately. The findings showed that proper laboratory equipment and appropriate laboratory kits are necessary for the rapid and precise identification of COVID-19.

SARS-CoV-2 Infection in Healthcare Professionals and General Population During "First Wave" of COVID-19 Pandemic: A Cross-Sectional Study Conducted in Sicily, Italy

On December 31, 2019, an outbreak of lower respiratory infections was documented in Wuhan caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the beginning, SARS-CoV-2 has caused many infections among healthcare workers (HCWs) worldwide. Aims of this study were: a. to compare the distribution among the HCWs and the general population of SARS-CoV-2 infections in Western Sicily and Italy; b. to describe the characteristics of HCWs infected with SARS-CoV-2 in the western Sicilian healthcare context during the first wave of the epidemic diffusion in Italy. Incidence and mean age of HCWs infected with SARS-CoV-2 were comparable in Western Sicily and in the whole Italian country. The 97.6% of infections occurred in HCWs operating in non-coronavirus disease 2019 (COVID-19) working environments, while an equal distribution of cases between hospital and primary care services context was documented. Nurses and healthcare assistants, followed by physicians, were the categories more frequently infected by SARS-CoV-2. The present study suggests that healthcare workers are easily infected compared to the general population but that often infection could equally occur in hospital and non-hospital settings. Safety of HCWs in counteracting the COVID-19 pandemic must be strengthened in hospital [adequate provision of personal protective equipment (PPE), optimization of human resources, implementation of closed and independent groups of HCWs, creation of traffic control building and dedicated areas in every healthcare context] and non-hospital settings (influenza vaccination, adequate psychophysical support, including refreshments during working shifts, adequate rest, and family support).

Socioeconomic and Behavioral Correlates of COVID-19 Infections among Hospital Workers in the Greater Jakarta Area, Indonesia: A Cross-Sectional Study

(1) Background: because of close contacts with COVID-19 patients, hospital workers are among the highest risk groups for infection. This study examined the socioeconomic and behavioral correlates of COVID-19 infection among hospital workers in Indonesia, the country hardest-hit by the disease in the Southeast Asia region. (2) Methods: we conducted a cross-sectional study, which collected data from 1397 hospital staff from eight hospitals in the Greater Jakarta area during April-July 2020. The data was collected using an online self-administered questionnaire and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) tests. We employed descriptive statistics and adjusted and unadjusted logistic regressions to analyze the data of hospital workers as well as the subgroups of healthcare and non-healthcare workers. (3) Results: from a total of 1397 hospital staff in the study, 22 (1.6%) were infected. In terms of correlates, being a healthcare worker (adjusted odds ratio (AOR) = 8.31, 95% CI 1.27-54.54) and having a household size of more than five (AOR = 4.09, 1.02-16.43) were significantly associated with a higher risk of infection. On the other hand, those with middle- and upper-expenditure levels were shown to have a lower risk of infection (AOR = 0.06, 0.01-0.66). Behavioral factors associated with COVID-19 infection among healthcare and non-healthcare workers included knowledge of standard personal protective equipment (PPE) (AOR = 0.08, 0.01-0.54) and application of the six-step handwashing technique (AOR = 0.32, 0.12-0.83). (4) Conclusion: among hospital staff, correlates of COVID-19 infection included being a healthcare worker, household size, expenditure level, knowledge and use of PPE, and application of appropriate hand washing techniques.

Seroprevalence of SARS-CoV-2 infection in health care workers of a teaching hospital in Belgium: self-reported occupational and household risk factors for seropositivity

This study aims to evaluate SARS-CoV-2 seroprevalence among health care workers (HCWs) and to assess self-reported risk factors for seropositivity. A total of 3255 HCWs were included and the overall seroprevalence was 7.8%. The likelihood of seropositivity was higher in participants reporting any COVID-19 symptoms within the last 4 months (OR 8.32, 95% CI 5.83-11.88, P < 0.001). Being a female HCW (OR 1.32, 95% CI 1.11–2.32, P < 0.01), having a cohabitant who was infected with SARS-CoV-2 (OR 2.55, 95% CI 1.78–3.66 P < 0.001) or a cohabitant who was a nursing home caregiver (OR 3.71, 95% CI 1.59–8.65, P = 0.002) were independently associated with an increased risk of seropositivity. Working in a COVID-19 unit (OR 1.64, 95% CI 1.21–2.23, P < 0.001) and being exposed to a SARS-CoV-2 infected co-worker (OR 1.30,95% CI 0.97–1.74, P = 0.016) resulted in higher seropositivity rate. Even if in-hospital exposure may play a significant role, increased infection risk is most likely attributable to household contact.

Seroprevalence of SARS-CoV-2 Antibodies in Adults and Healthcare Workers in Southern Italy

BACKGROUND

This study was carried out to estimate the seroprevalence of SARS-CoV-2 antibodies in a Southern Italian population.

METHODS

The study was performed among students and workers of the University of Campania "Luigi Vanvitelli" and the relative Teaching Hospital. Participants were invited to undergo a blood sampling, an interview or to complete a self-administered questionnaire.

RESULTS

A total of 140 participants (5.8%) tested positive for SARS-CoV-2 antibodies. Positive SARS-CoV-2 test results increased significantly during the months of testing, and those who had had at least one symptom among fever, cough, dyspnea, loss of taste or smell and who had had contact with a family member/cohabitant with confirmed COVID-19 were more likely to test positive. Faculty members were less likely to have a positive test result compared to the healthcare workers (HCWs). Among HCWs, physicians showed the lowest rate of seroconversion (5.2%) compared to nurses (8.9%) and other categories (10%). Nurses and other HCWs compared to the physicians, those who had had at least one symptom among fever, cough, dyspnea, loss of taste or smell, and who had had contact with a family member/cohabitant with confirmed COVID-19 were more likely to test positive.

CONCLUSIONS

The results have demonstrated that SARS-CoV-2 infection is rapidly spreading even in Southern Italy and confirm the substantial role of seroprevalence studies for the assessment of SARS-CoV-2 infection circulation and potential for further spreading.

Seroprevalence of SARS-CoV-2 antibody among healthcare workers in a university hospital in Mallorca, Spain, during the first wave of the COVID-19 pandemic

OBJECTIVE

To estimate the SARS-CoV-2 antibody seroprevalence in healthcare workers (HCWs) at a university hospital in Mallorca, Spain.

METHODS

All HCWs received an e-mail inviting them to take part in the study. Participants had a nasopharyngeal swab test performed for reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and serological tests to detect SARS-CoV-2 antibodies (primary study). Additionally, they were invited to complete a questionnaire on their exposure to COVID-19 individuals and their COVID-19-related symptoms (secondary study). Prevalence of antibodies (IgG, IgM, or both) and 95% confidence intervals (CIs) were calculated.

RESULTS

Seventy-nine percent of the hospital's HCWs (N = 2210) took part in the primary study. Antibodies were detected in 61 participants, a prevalence of 2.8% (95% CI: 2.5-3.1). The prevalence was slightly higher in nurses (3.4%), registrars (3.9%), and wardens (3.4%). Thirty-nine percent of the primary study participants completed the secondary study questionnaire. Those with positive antibody test results had closer contact with COVID-19 individuals (60% vs. 92%; p < 0.001).

CONCLUSION

After the first wave of the COVID-19 pandemic in Spain, the seroprevalence of SARS-CoV-2 antibodies in our university hospital HCWs was around 2.8%, which is slightly higher than the seroprevalence in the general population in our region. We believe it would be advisable to perform additional seroprevalence studies during the second wave of the epidemic.

SARS-CoV-2 RT-PCR positivity and antibody prevalence among asymptomatic hospital-based health care workers

Background

The level of asymptomatic infection with SARS-CoV-2 could be substantial and among health care workers (HCWs) a source of continuing transmission of the virus to patients and co-workers.

Objectives

Measure the period prevalence of SARS-CoV-2 PCR positivity and seroprevalence of SARS-CoV-2 IgG antibodies among a random sample of asymptomatic health system hospital-based health care workers (HCWs) 6½ -15½ weeks after 4/5/2020, the peak of the first surge of COVID-19 admissions.

Results

Of 524 eligible and consented participants from four metropolitan hospitals, nasopharyngeal swabs were obtained from 439 (83.8 %) and blood from 374 (71.4 %). Using PCR nucleic acid-based amplification (NAAT) methods, the period prevalence of SARS-CoV-2 infection was 0.23 % (95 % confidence interval (CI) 0.01 %–1.28 %; 1/439) from 5/21/20−7/16/20. The seroprevalence of SARS-CoV-2 IgG antibodies from June 17-July 24, 2020 was 2.41 % (95 % CI 1.27 %–4.51 %; 9/374). Those who were reactive were younger (median age 36 versus 44 years; p = 0.050), and those with self-reported Hispanic/Latino ethnicity had a higher seroprevalence (2/12 = 16.7 % versus 7/352 = 2.0 %; p = 0.051). There were no significant differences by sex, race, residence, hospital, unit or job type. The one employee who was found to be PCR test positive in this study was also reactive for IgG antibodies, tested 27 days later.

Conclusions

The period prevalence of PCR positivity to SARS-CoV-2 and IgG seroprevalence was unexpectedly low in asymptomatic HCWs after a peak in COVID-19 admissions and the establishment of state and institutional infection control policies, suggesting that routine screening tests while community prevalence is relatively low would produce a minimal yield.

SARS-CoV-2-Specific Neutralizing Antibody Responses in Norwegian Health Care Workers After the First Wave of COVID-19 Pandemic: A Prospective Cohort Study

BACKGROUND

During the coronavirus disease 2019 (COVID-19) pandemic, many countries experienced infection in health care workers (HCW) due to overburdened health care systems. Whether infected HCW acquire protective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unclear.

METHODS

In a Norwegian prospective cohort study, we enrolled 607 HCW before and after the first COVID-19 wave. Exposure history, COVID-19-like symptoms, and serum samples were collected. SARS-CoV-2-specific antibodies were characterized by spike-protein IgG/IgM/IgA enzyme-linked immunosorbent and live-virus neutralization assays.

RESULTS

Spike-specific IgG/IgM/IgA antibodies increased after the first wave in HCW with, but not in HCW without, COVID-19 patient exposure. Thirty-two HCW (5.3%) had spike-specific antibodies (11 seroconverted with ≥4-fold increase, 21 were seropositive at baseline). Neutralizing antibodies were found in 11 HCW that seroconverted, of whom 4 (36.4%) were asymptomatic. Ninety-seven HCW were tested by reverse transcriptase polymerase chain reaction (RT-PCR) during follow-up; 8 were positive (7 seroconverted, 1 had undetectable antibodies).

CONCLUSIONS

We found increases in SARS-CoV-2 neutralizing antibodies in infected HCW, especially after COVID-19 patient exposure. Our data show a low number of SARS-CoV-2-seropositive HCW in a low-prevalence setting; however, the proportion of seropositivity was higher than RT-PCR positivity, highlighting the importance of antibody testing.

COVID-19 Screening Program Should be Performed in Healthcare Workers

The screening test for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease 2019 (COVID-19) has not been performed in healthcare workers (HCWs) yet, although HCWs are at a high risk of infection. COVID-19 is detected in 5%-15% of HCWs according to published studies. Nevertheless, it may be higher than the rates indicated in published studies. Based on this fact, the current recommendation of studies in the literature is to screen COVID-19 in HCWs. In this review, studies on SARS-CoV-2 screening in HCWs will be reconsidered, and the frequency and target group in whom screening should be performed will be emphasized.

Seroprevalence of SARS-CoV-2 IgG antibodies among health care workers prior to vaccine administration in Europe, the USA and East Asia: A systematic review and meta-analysis

BACKGROUND

Knowing the seroprevalence of SARS-CoV-2 IgG antibodies across geographic regions before vaccine administration is one key piece of knowledge to achieve herd immunity. While people of all ages, occupations, and communities are at risk of getting infected with SARS-CoV-2, the health care workers (HCWs) are possibly at the highest risk. Most seroprevalence surveys with HCWs conducted worldwide have been limited to Europe, North America, and East Asia. We aimed to understand how the seroprevalence of SARS-CoV-2 IgG antibodies varied across these geographic regions among HCWs based on the available evidences.

METHODS

By searching through PubMed, ScienceDirect, and Google Scholar databases, eligible studies published from January 1, 2020 to January 15, 2021 were included for the systematic review and meta-analysis. The random-effects model was used to estimate the pooled proportion of IgG seropositive HCWs. Publication bias was assessed by funnel plot and confirmed by Egger's test. Heterogeneity was quantified using I2 statistics. We performed sensitivity analyses based on sample size, diagnostic method and publication status. The study protocol was registered with PROSPERO (CRD42020219086).

FINDINGS

A total of 53 peer-reviewed articles were selected, including 173,353 HCWs (32.7% male) from the United States, ten European, and three East Asian countries. The overall seropositive prevalence rate of IgG antibodies was 8.6% in these regions (95% CI= 7.2-9.9%). Pooled seroprevalence of IgG antibodies was higher in studies conducted in the USA (12.4%, 95% CI= 7.8-17%) than in Europe (7.7%, 95% CI=6.3-9.2%) and East Asia (4.8%, 95% CI=2.9-6.7%). The subgroup study also estimated that male HCWs had 9.4% (95% CI= 7.2-11.6%) IgG seroconversion, and female HCWs had 7.8% (95% CI=5.9-9.7%). The study exhibits a high prevalence of IgG antibodies among HCWs under 40 years in the USA, conversely, it was high in older HCWs (≥40 years of age) in Europe and East Asia. In the months February-April 2020, the estimated pooled seroprevalence was 5.7% (4.0-7.4%) that increased to 8·2% (6.2-10%) in April-May and further to 9.9% (6.9-12.9%) in the May-September time-period.

INTERPRETATION

In the view of all evidence to date, a significant variation in the prevalence of SARS-CoV-2 antibodies in HCWs is observed in regions of Europe, the United States, and East Asia. The patterns of IgG antibodies by time, age, and gender suggest noticeable regional differences in transmission of the virus. Based on the insights driven from the analysis, priority is required for effective vaccination for older HCWs from Europe and East Asia. A considerable high seroprevalence of IgG among HCWs from the USA suggests a high rate of past infection that indicates the need to take adequate measures to prevent hospital spread. Moreover, the seroprevalence trend was not substantially changed after May 2020, suggesting a slow progression of long-term SARS-CoV-2 immunity. Routine testing of HCWs for SARS-CoV-2 should be considered even after the rollout of vaccination to identify the areas of increased transmission.

FUNDING

None.

Prevalence of Anti-SARS-CoV-2 Antibody in Hospital Staff in Double-Center Setting: A Preliminary Report of a Cohort Study From Iran

Background: The outbreak of COVID-19 in China in late 2019 was an unprecedented catastrophe that also involved many other countries, including Iran. Concerning the danger of disease contagion, it is necessary to detect asymptomatic or mild cases, especially in hospital staff who are highly exposed to the disease. Objectives: In this serosurvey study, we aimed to estimate IgG seroprevalence among hospital staff in two public hospitals to determine local transmission and infection risk factors, as well as protective immunity among high-risk populations. Methods: Screening was offered to the hospital staff of two public hospitals in Shiraz, Iran. Screening involved the measurement of IgG antibodies against SARS-CoV-2. Besides, a checklist that consisted of questions about sociodemographic, occupational, and epidemiological characteristics was completed by the participants. Results: Among 494 participants in this study, 29 (5.8%) had anti-SARS-CoV-2 IgG in their blood. Besides, 320 (64.8%) had at least one of the clinical symptoms within six months before this survey. Among participants with positive PCR, nine (21.4%) had anti-SARS-CoV-2 IgG, while this figure was seven (33.3%) for individuals with positive CT scans. Non-proper disposal of used protective equipment or infectious wastes (OR = 26.5), rotational daily work shifts (OR = 7.5), being anxious about getting COVID-19 (OR = 3.8), and age (OR = 1.06) were the significant determinants of having anti-SARS-CoV-2 IgG in the hospital staff. Conclusions: It is essential to continue training and giving technical consultations about COVID-19, especially the proper disposal of used protective equipment or infectious wastes in rotational daily shift workers.

High SARS-CoV-2 Seroprevalence in Healthcare Workers in Bukavu, Eastern Democratic Republic of Congo

Among 359 healthcare workers (HCW) employed in Panzi General Referral Hospital located in Bukavu in the Democratic Republic of Congo, 148 (41.2%) tested positive for SARS-CoV-2 antibodies. Thirty-three (22.3%) of the 148 personnel with positive serology reported symptoms evoking a prior COVID-19 illness. None of the infected HCWs reported COVID-related hospitalization, and all of them recovered. Our findings indicate high and underestimated circulation of SARS-CoV-2 within the Bukavu area.