Cohort Of Healthcare Workers Research Articles

Immunity Induced by Inactivated SARS-CoV-2 Vaccine: Breadth, Durability, Potency, and Specificity in a Healthcare Worker Cohort.

Vaccination has proven to be highly effective against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the long-term immunogenicity and the functional preserved immune responses of vaccines are needed to inform evolving evidence-based guidelines for boosting schedules. We enrolled 205 healthcare workers into a cohort study; all had received three doses of BBIBP-CorV (China Sinopharm Bio-Beijing Company, Beijing, China) inactivated vaccine. We assessed SARS-CoV-2 specific binding antibodies, neutralizing antibodies, and peripheral T and B cell responses. We demonstrated that more robust antibody responses to SARS-CoV-2 were elicited by booster immunization compared with primary vaccination. Neutralizing antibody titers to SARS-CoV-2 Omicron BA.1 were also efficiently elevated post-homologous vaccine booster despite being in a lower titer compared with the prototype stain. In addition to S-specific humoral and cellular immunity, BBIBP-CorV also induced N-specific antibody and effector T cell responses. The third-dose vaccination led to further expansion of critical polyfunctional T cell responses, likely an essential element for vaccine protection. In particular, a functional role for Tfh cell subsets in immunity was suggested by the correlation between both CD4+ Tfh and CD8+ Tfh with total antibody, IgG, B cell responses, and neutralizing antibodies. Our study details the humoral and cellular responses generated by the BBIBP-CorV booster vaccination in a seven-month follow-up study. There is a clear immunologic boosting value of homologous inactivated SARS-CoV-2 vaccine boosters, a consideration for future vaccine strategies.

Primary Series and Booster Coronavirus Disease 2019 Vaccine Effectiveness in a Cohort of Healthcare Workers in Albania During a BA.1 and BA.2 Variant Period, January-May 2022.

Healthcare workers (HCWs) have experienced high rates of coronavirus disease 2019 (COVID-19) morbidity and mortality. We estimated COVID-19 2-dose primary series and monovalent booster vaccine effectiveness (VE) against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron (BA.1 and BA.2) infection among HCWs in 3 Albanian hospitals during January-May 2022. Study participants completed weekly symptom questionnaires, underwent polymerase chain reaction (PCR) testing when symptomatic, and provided quarterly blood samples for serology. We estimated VE using Cox regression models (1 - hazard ratio), with vaccination status as the time-varying exposure and unvaccinated HCWs as the reference group, adjusting for potential confounders: age, sex, prior SARS-CoV-2 infection (detected by PCR, rapid antigen test, or serology), and household size. At the start of the analysis period, 76% of 1462 HCWs had received a primary series, 10% had received a booster dose, and 9% were unvaccinated; 1307 (89%) HCWs had evidence of prior infection. Overall, 86% of primary series and 98% of booster doses received were BNT162b2. The median time interval from the second dose and the booster dose to the start of the analysis period was 289 (interquartile range [IQR], 210-292) days and 30 (IQR, 22-46) days, respectively. VE against symptomatic PCR-confirmed infection was 34% (95% confidence interval [CI], -36% to 68%) for the primary series and 88% (95% CI, 39%-98%) for the booster. Among Albanian HCWs, most of whom had been previously infected, COVID-19 booster dose offered improved VE during a period of Omicron BA.1 and BA.2 circulation. Our findings support promoting booster dose uptake among Albanian HCWs, which, as of January 2023, was only 20%. Clinical Trials Registration. NCT04811391.

Using BCG Vaccine to Enhance Nonspecific Protection of Health Care Workers During the COVID-19 Pandemic: A Randomized Controlled Trial.

The BCG (Bacillus Calmette-Guérin) vaccine can induce nonspecific protection against unrelated infections. We aimed to test the effect of BCG on absenteeism and health of Danish health care workers (HCWs) during the coronavirus disease 2019 (COVID-19) pandemic. A single-blinded randomized controlled trial included 1221 HCWs from 9 Danish hospitals. Participants were randomized 1:1 to standard dose BCG or placebo. Primary outcome was days of unplanned absenteeism. Main secondary outcomes were incidence of COVID-19, all-cause hospitalization, and infectious disease episodes. There was no significant effect of BCG on unplanned absenteeism. Mean number of days absent per 1000 workdays was 20 in the BCG group and 17 in the placebo group (risk ratio, 1.23; 95% credibility interval, 0.98-1.53). BCG had no effect on incidence of COVID-19 or all-cause hospitalization overall. In secondary analyses BCG revaccination was associated with higher COVID-19 incidence (hazard ratio [HR], 2.47; 95% confidence interval [CI], 1.07-5.71), but also reduced risk of hospitalization (HR, 0.28; 95% CI, .09-.86). The incidence of infectious disease episodes was similar between randomization groups (HR, 1.09; 95% CI, .96-1.24). In this relatively healthy cohort of HCWs, there was no overall effect of BCG on any of the study outcomes. NCT0437329 and EU Clinical Trials Register (EudraCT number 2020-001888-90).

Longitudinal kinetics of neutralizing antibodies against circulating SARS-CoV-2 variants and estimated level of group immunity of booster-vaccinated individuals during omicron-dominated COVID-19 outbreaks in the Republic of Korea, 2022.

The coronavirus disease 2019 pandemic persisted for 3 years and is now transitioning to endemicity. We illustrated the change in group immunity induced by vaccination (monovalent vaccines) and breakthrough infections (BIs) in a healthcare worker (HCW) cohort. Five sampling points were analyzed: before the third dose and 1, 3, 5, and 8 months after the vaccination. The last two points corresponded roughly to 1 and 4 months after omicron BA.1/BA.2 BI. A semi-quantitative anti-spike binding antibody (Sab) assay and plaque reduction neutralization test (PRNT) against circulating variants were conducted. A linear regression model was utilized to deduce correlation equations. Baseline characteristics and antibody titers after the third dose were not different between 106 HCWs with or without BI (54/52). One month after the third dose, BA.1 PRNT increased with wild-type (WT), but 3 months after the third dose, it decreased more rapidly than WT PRNT. After BI, BA.1 PRNT increased robustly and waned slower than WT. A linear equation of waning kinetics was deduced between log10Sab and months, and the slope became gradual after BI. The estimated BA.5 PRNT titers at the beginning of the BA.5 outbreak were significantly higher than the BA.1 PRNT titers of the initial BA.1/BA.2 wave, which might be associated with the smaller size of the BA.5 wave. BA.1/BA.2 BI after the third dose elicited robust and broad neutralizing activity, preferentially maintaining cross-neutralizing longevity against BA.1 and BA.5. The estimated kinetics provide an overview of group immunity through the third vaccination and BA.1/BA.2 BI, correlating with the actual outbreaks. IMPORTANCE This study analyzed changes in group immunity induced by coronavirus disease 2019 (COVID-19) vaccination and BA.1/BA.2 breakthrough infections (BIs) in a healthcare worker cohort. We investigated the longitudinal kinetics of neutralizing antibodies against circulating variants and confirmed that BA.1/BA.2 BIs enhance the magnitude and durability of cross-neutralization against BA.1 and BA.5. Correlation equations between semi-quantitative anti-spike antibody and plaque reduction neutralization test titers were deduced from the measured values using a linear regression model. Based on the equations, group immunity was estimated to last up to 11 months following the third dose of the COVID-19 vaccine. The estimated group immunity suggests that the augmented immunity and flattened waning slope through BI could correlate with the overall outbreak size. Our findings could provide a better understanding to establish public health strategies against future endemicity.

Parenting stress and associated factors in healthcare workers after the second wave of COVID-19 in India: a two-center cross-sectional study.

High parenting stress (PS) in members of the general population during the COVID-19 pandemic was exacerbated by work-, family-, and child-related factors. However, the negative effects of PS on the mental health and work participation of healthcare workers (HCWs) have received limited attention. This study aimed to examine the proportion of severe PS among HCWs and identify its contributory factors. This cross-sectional survey was conducted in two COVID-19-care hospitals attached to medical colleges in India between November 1 and December 24, 2021, following the delta variant-driven second wave of COVID-19. The study recruited 662 HCW parent and child dyads (aged 1.5-18 years) and assessed workplace, family, and child-related characteristics. The Parenting Stress Scale (PSS) and Child Behavior Checklist (CBCL) were used to identify severe PS and child behavioral issues, respectively. Univariable and multivariable logistic regression analyzes were used to identify the significant and independent risk factors associated with severe PS, respectively. Equal proportions of medical and paramedical HCWs completed the survey [mean age: 36.96 ± 5.89; female: 466 (70%)]. The median PSS score of HCWs was 33 [interquartile range (IQR): 28-39], and 23% (155/662) of the HCW parents experienced severe PS. The independent predictors of severe PS included the female sex [adjusted odds ratio (aOR): 3.31; 95% confidence interval (CI): 1.74-6.29], HCWs with >15-day postings in COVID-19 care (aOR: 3.74; 95% CI: 1.53-9.16), having children with behavioral issues (aOR: 3.49; 95% CI: 1.29-9.48), HCWs at the Dehradun center (aOR: 2.25; 95% CI: 1.24-4.10), having an HCW spouse simultaneously working in COVID-19 care (aOR: 1.88; 95% CI: 1.01-3.49), and HCWs with joint families (aOR: 1.93; 95% CI: 1.17-3.18). Overall, 23% of the cohort of HCWs continued to experience severe PS after the second COVID-19 wave driven by the delta variant in India. Routine screening of HCWs for PS using the PSS or similar measures, anticipatory guidance for parenting, and targeting at-risk HCWs with appropriate supportive measures may help reduce the incidence of severe PS and optimize the participation of HCWs in the fight against current and future pandemic-like situations.

SARS-CoV-2 risk in household contacts of healthcare workers: a prospective cohort study

BackgroundFew studies have assessed whether the increased SARS-CoV-2 risk of healthcare workers (HCW) is carried on to their household contacts. Within a prospective HCW cohort, we assessed the SARS-CoV-2 risk of household contacts of HCW depending on the HCWs cumulative exposure to COVID-19 patients and identified factors influencing this association.MethodsHCW aged ≥ 16 years from nine Swiss healthcare networks participated. HCW without any household contacts were excluded. For HCW, cumulative patient exposure (number of COVID-19 patient contacts times average contact duration during a 12-month follow-up) was calculated. During follow-up, HCW reported SARS-CoV-2 nasopharyngeal swab results and positive swab results of their household contacts. We used multivariable logistic regression to identify variables associated with SARS-CoV-2 household positivity.ResultsOf 2406 HCW, 466 (19%) reported ≥ 1 SARS-CoV-2 positive household. In multivariable analysis, patient exposure of HCW (adjusted OR [aOR] 1.08 per category, 95% CI 1.04–1.12), household size (aOR 1.53 per household member, 95% CI 1.35–1.73) and having children (aOR 0.70, 95% CI 0.53–0.94) remained associated with household positivity. Vaccinated HCW had a lower risk (aOR 0.54, 95% CI 0.38–0.77) of reporting a positive contact, as were those using respirator masks in contact with COVID-19 patients (aOR 0.65, 95% CI 0.49–0.86). Among vaccinated HCW, delayed first vaccination was associated with increased household SARS-CoV-2 positivity (aOR 1.14 per month, 95% CI 1.08–1.21).ConclusionsSARS-CoV-2 positivity in household contacts of HCW increases with higher cumulative COVID-19 patient exposure of HCWs. Measures reducing the SARS-CoV-2 risk in HCW might indirectly reduce the infection risk of their households.

Incidence of anti-platelet factor4/polyanionic antibodies, thrombocytopenia, and thrombosis after COVID-19 vaccination with ChAdOx1 nCoV-19 in Thais

BackgroundThe prevalence of anti-platelet factor 4 (PF4)/polyanionic antibodies occurring after vaccination with ChAdOx1 nCoV-19 is low. Most of these antibodies are not associated with vaccine-induced thrombotic thrombocytopenia. It remains unknown whether these antibodies are preexisting or occur as a result of vaccination. In this study, we demonstrated the incidence of anti-PF4/polyanionic antibodies, thrombocytopenia, and thrombosis after vaccination with ChAdOx1 nCoV-19 in a large cohort of Thais.MethodsWe conducted a prospective study in a cohort of health care workers and members of the general population who received COVID-19 vaccination with ChAdOx1 nCoV-19. Blood collection for complete blood count, D-dimer, and anti-PF4/polyanionic antibodies was performed before vaccination (day 0), day 10, and day 28 after vaccination. Anti-PF4/polyanionic antibodies were detected using enzyme-link immunosorbent assay (ELISA). Functional assay was performed for all positive ELISA tests.ResultsA total of 720 participants were included in the study. 214 participants received both the first and second doses, 91 participants received only the first, 51 received only the second, and 364 received the third booster dose of ChAdOx1 nCoV-19. Median age was 42 years (IQR, 34–53). 67% of participants were female. Three participants developed seroconversion, yielding an incidence of vaccination-induced anti-PF4/polyanionic antibodies of 0.42% (95% confidence interval 0.08, 1.23). Fourteen (1.9%) participants had preexisting anti-PF4/polyanionic antibodies before the vaccination but their optical density of anti-PF4/polyanionic antibodies did not significantly increase over time. None of the anti-PF4/polyanionic positive sera induced platelet aggregation. Abnormal D-dimer levels following vaccination were not different among the positive and negative anti-PF4/polyanionic groups (11.8% vs. 13.2%, p = 0.86). Thrombocytopenia occurred in one person with negative anti-PF4/polyanionic antibodies. No clinical thrombosis or bleeding occurred.ConclusionWe found a low incidence of seroconversion of anti-PF4/polyanionic antibodies after vaccination with ChAdOx1 nCoV-19 in Thais. Most of the anti-PF4/polyanionic antibodies were preexisting and did not significantly increase after vaccination with ChAdOx1 nCoV-19. Following vaccination, some participants with anti-PF4/polyanionic antibodies had elevated D-dimer levels, while only one developed thrombocytopenia and no thrombotic events were observed.

A prospective longitudinal cohort study on risk factors for COVID-19 vaccination failure (RisCoin): methods, procedures and characterization of the cohort

The primary objective of the RisCoin study was to investigate the interplay of genetic, metabolic, and lifestyle factors as well as stress levels on influencing the humoral immune response after at least two COVID-19 vaccinations, primarily with mRNAs, and the risk of SARS-CoV-2 breakthrough infections during follow-up. Here, we describe the study design, procedures, and study population. RisCoin is a prospective, monocentric, longitudinal, observational cohort study. Between October and December 2021, 4515 participants with at least two COVID-19 vaccinations, primarily BNT162b2 and mRNA-1273, were enrolled at the LMU University Hospital of Munich, thereof > 4000 healthcare workers (HCW), 180 patients with inflammatory bowel disease under immunosuppression, and 119 patients with mental disorders. At enrollment, blood and saliva samples were collected to measure anti-SARS-CoV-2 antibodies, their neutralizing capacity against Omicron-BA.1, stress markers, metabolomics, and genetics. To ensure the confidential handling of sensitive data of study participants, we developed a data protection concept and a mobile application for two-way communication. The application allowed continuous data reporting, including breakthrough infections by the participants, despite irreversible anonymization. Up to 1500 participants attended follow-up visits every two to six months after enrollment. The study gathered comprehensive data and bio-samples of a large representative HCW cohort and two patient groups allowing analyses of complex interactions. Our data protection concept combined with the mobile application proves the feasibility of longitudinal assessment of anonymized participants. Our concept may serve as a blueprint for other studies handling sensitive data on HCW.

Effectiveness of repetitive influenza vaccination against SARS-CoV-2 infection among a cohort of health care workers in Portugal.

Vaccination for influenza has been essential over the years to protect the most vulnerable populations. Moreover, it was recently suggested that influenza vaccination might confer some nonspecific immunity to other viruses and be associated with a lower risk for coronavirus disease 2019 (COVID-19) morbidity and mortality. Therefore, we aimed to assess the effectiveness of repetitive influenza vaccination against SARS-CoV-2 infection in a cohort of health care workers (HCWs). This study was conducted among HCWs at São João University Hospital Center (CHUSJ), Porto, Portugal, a tertiary reference hospital for diagnosis and therapy, one of the largest hospitals in the country with approximately 6000 HCWs. We analyzed databases for influenza vaccination conducted between 2012 and 2019 and COVID-19 laboratory testing retrieved from the first and last registered positive COVID test date before HCW's COVID-19 vaccination started. The study outcome was the incidence of the first SARS-CoV-2 infection, as determined by reverse transcription polymerase chain reaction (RT-PCR). Age and sex were considered potential confounders. We used multivariable Cox regression to estimate odds ratios. Neither the absolute number nor the proportion of influenza shots influenced the risk of getting infected by SARS-CoV-2 (adjusted odds ratio 1.02, 95% CI: 0.9-1.06 and 1.17 95% CI: 0.86-1.58, respectively). Similar findings were observed in most cases when the analysis was restricted by year. The findings from our retrospective observational analysis of a HCWs cohort failed to support any protective effect between repetitive influenza vaccination and SARS-CoV-2 infection.

Investigating the impact of financial concerns on symptoms of depression in UK healthcare workers: data from the UK-REACH nationwide cohort study.

Exploration of the association between financial concerns and depression in UK healthcare workers (HCWs) is paramount given the current 'cost of living crisis', ongoing strike action and recruitment/retention problems in the National Health Service. To assess the impact of financial concerns on the risk of depression in HCWs, how these concerns have changed over time and what factors might predict financial concerns. We used longitudinal survey data from a UK-wide cohort of HCWs to determine whether financial concerns at baseline (December 2020 to March 2021) were associated with depression (measured with the Public Health Questionnaire-2) at follow-up (June to October 2022). We used logistic regression to examine the association between financial concerns and depression, and ordinal logistic regression to establish predictors of developing financial concerns. A total of 3521 HCWs were included. Those concerned about their financial situation at baseline had higher odds of developing depressive symptoms at follow-up. Financial concerns increased in 43.8% of HCWs and decreased in 9%. Those in nursing, midwifery and other nursing roles had over twice the odds of developing financial concerns compared with those in medical roles. Financial concerns are increasing in prevalence and predict the later development of depressive symptoms in UK HCWs. Those in nursing, midwifery and other allied nursing roles may have been disproportionately affected. Our results are concerning given the potential effects on sickness absence and staff retention. Policy makers should act to alleviate financial concerns to reduce the impact this may have on a discontent workforce plagued by understaffing.

Kinetics of SARS-CoV-2 Serum Antibodies Through the Alpha, Delta, and Omicron Surges Among Vaccinated Health Care Workers at a Boston Hospital.

Longitudinal serology studies can assist in analyzing the kinetics of antibodies to SARS-CoV-2, helping to inform public health decision making. Our study aims to characterize circulating antibody trends over 18 months in vaccinated participants with and without evidence of COVID-19 infection. A cohort of health care workers employed at Boston Medical Center was followed to collect serum samples and survey data over 6 time points from July 2020 through December 2021 (N = 527). History of SARS-CoV-2 infection, vaccination, and booster status were confirmed, where possible, through electronic medical records. Serum was assessed for the qualitative and semiquantitative detection of IgG antibody levels (anti-nucleoprotein [anti-N] and anti-spike [anti-S], respectively). Piecewise regression models were utilized to characterize antibody kinetics over time. Anti-S IgG titers remained above the positivity threshold following infection and/or vaccination throughout the 18-month follow-up. Among participants with no evidence of COVID-19 infection, titers declined significantly faster in the initial 90 days after full vaccination (β = -0.056) from December 2020 to March 2021 as compared with the decline observed following booster dose uptake (β = -0.023, P < 0.001). Additionally, COVID-19 infection prior to vaccination significantly attenuated the decline of anti-S IgG when compared with no infection following vaccine uptake (P < 0.001). Lastly, fewer participants contracted Omicron when boosted (12.7%) compared to fully vaccinated (17.6%). Regardless of vaccination status, participants who were Omicron positive had lower anti-S IgG titers than those who did not test positive, but this difference was not significant. These findings provide novel 18-month kinetics of anti-S IgG antibodies and highlight the durability of hybrid immunity, underlining the strong humoral response stimulated by combined infection and vaccination.

Incidence of shoulder disorders in a cohort of healthcare workers from 2009 to 2020

PurposeTo estimate the incidence of shoulder disorders in a cohort of Health Care Workers (HCWs).Methods4406 workers employed from 2009 to 2020, were included in the study. Occupational risk factors and jobs were assessed according to working history. Incident cases were defined in case of shoulder pain associated with functional limitations during the medical examination. The Cox regression model was used to calculate the Hazard Ratio (HR) for different work activities, adjusted for age, sex, body mass index, and previous musculoskeletal injuries, using clerks as the reference category.ResultsThe incidence rates of shoulder musculoskeletal disorder for men and women were 13.1 for 1000 person-years (CI 95% 10.6–16.3) and 20.1 for 1000 person-years (CI 95% 17.8–22.6) respectively. The adjusted HR was significantly increased with age (1.06, CI 95% 1.05–1.07), outpatient health activities (2.82, CI 95% 1.89–4.219), and wards health activity (2.37, CI 95% 1.68–3.33).ConclusionHCWs with high biomechanical risk such as nurses and healthcare assistants had a higher incidence of shoulder disorders. Actions are needed for better prevention in health care assistance.

Retrospective evaluation of factors affecting successful fit testing of respiratory protective equipment during the early phase of COVID-19

ObjectivesRespiratory protective equipment is critical to protect healthcare workers from COVID-19 infection, which includes filtering facepiece respirators (FFP3). There are reports of fitting issues within healthcare workers, although the factors...

Prevalence of observed BCG scar in a cohort of health care workers from three Lusophone sub-Saharian African countries: cross-sectional comparative study

Prevalence of observed BCG scar in a cohort of health care workers from three Lusophone sub-Saharian African countries: cross-sectional comparative study

Pentraxin (PTX-3) as a prognostic marker of clinical implication of COVID-19 in a cohort of healthcare workers from the A.O.U. 'G. Martino' of Messina

Pentraxin (PTX-3) as a prognostic marker of clinical implication of COVID-19 in a cohort of healthcare workers from the A.O.U. 'G. Martino' of Messina

Differences in the Long-term Impact of the COVID-19 Pandemic on the Mental Health and Professional Quality of Life of Resident and Specialist Physicians.

The COVID-19 pandemic created an extremely difficult situation for healthcare workers (HCWs) worldwide. We aimed to compare the mental health and professional quality of life of residents and specialist physicians in a cohort of Italian HCWs caring for patients with COVID-19 about two years after the start of the COVID-19 pandemic. In November 2021, an online survey investigating the emotional states of depression, anxiety, stress, compassion satisfaction and compassion fatigue was administered to HCWs (N= 78) at the Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome. Our findings suggest that from 5 to 20% of our cohort of HCWs still showed the effects of the adverse psychological impact of the pandemic and more than half of them experienced medium levels of compassion fatigue as well as a medium level of compassion satisfaction. Our results also show that those with fewer years of clinical practice might be at greater risk of burnout (p= 0.021), anxiety and stress symptoms (both ps= 0.027) and might develop a lower level of compassion satisfaction (p=0.018). Moreover, the factors that potentially contribute to poor mental health, compassion fatigue and compassion satisfaction seem to differ between residents and specialist physicians. This overview presents one of the first pictures of the long-term effects of the pandemic on the mental health and professional quality of life of an Italian sample of HCWs. Moreover, it also helps identify professionals who are most in need of support and emphasises the importance of improving the psychological and professional wellbeing of these individuals especially during a pandemic-like crisis with long lasting effects.

Validation of N Protein Antibodies to Diagnose Previous SARS-CoV-2 Infection in a Large Cohort of Healthcare Workers: Use of Roche Elecsys® Immunoassay in the S Protein Vaccination Era.

The aim of this study was to validate the detection of anti-nucleocapsid protein (N protein) antibodies for the diagnosis of SARS-CoV-2 infection in light of the fact that most COVID-19 vaccines use the spike (S) protein as the antigen. Here, 3550 healthcare workers (HCWs) were enrolled from May 2020 (when no S protein vaccines were available). We defined SARS-CoV-2 infection if HCWs were found to be positive by RT-PCR or found to be positive in at least two different serological immunoassays. Serum samples from Biobanc I3PT-CERCA were analyzed by Roche Elecsys® (N protein) and Vircell IgG (N and S proteins) immunoassays. Discordant samples were reanalyzed with other commercial immunoassays. Roche Elecsys® showed the positivity of 539 (15.2%) HCWs, 664 (18.7%) were found to be positive by Vircell IgG immunoassays, and 164 samples (4.6%) showed discrepant results. According to our SARS-CoV-2 infection criteria, 563 HCWs had SARS-CoV-2 infection. The Roche Elecsys® immunoassay has a sensitivity, specificity, accuracy, and concordance with the presence of infection of 94.7%, 99.8%, 99.3%, and 0.96, respectively. Similar results were observed in a validation cohort of vaccinated HCWs. We conclude that the Roche Elecsys® SARS-CoV-2 N protein immunoassay demonstrated good performance in diagnosing previous SARS-CoV-2 infection in a large cohort of HCWs.

Risk Factors for Severe COVID-19 Among Healthcare Workers.

Evaluate potential risk factors for severe COVID-19 among healthcare workers at the University of Virginia Medical Center in Charlottesville, VA, USA. We conducted retrospective manual chart review of data from healthcare workers who were diagnosed with COVID-19 from March 2020 to March 2021. Using data from patient medical histories, we ascertained risk factors for COVID-19-related Emergency Department (ED) encounter, hospitalization, or death. We had 634 patients total and 9.8% had a severe COVID-19-related outcome. A history of deep vein thrombosis (DVT)/pulmonary embolism (PE)/stroke (OR 19.6 [5.11, 94.7]), as well as asthma, chronic lung disease, diabetes, or current immunocompromised status were associated with increased adjusted odds of COVID-19-related ED encounter/hospitalization/death. A pre-existing history of DVT/PE/stroke is a novel risk factor for poor COVID-19 outcomes among a cohort of health care workers.

A longitudinal analysis of humoral, T cellular response and influencing factors in a cohort of healthcare workers: Implications for personalized SARS-CoV-2 vaccination strategies.

SARS-CoV-2 mRNA vaccinations elicit both virus-specific humoral and T-cell responses, but a complex interplay of different influencing factors, such as natural immunity, gender, and age, guarantees host protection. The present study aims to assess the immune dynamics of humoral, T-cell response, and influencing factors to stratify individual immunization status up to 10 months after Comirnaty-vaccine administration. To this aim, we longitudinally evaluated the magnitude and kinetics of both humoral and T-cell responses by serological tests and enzyme-linked immunospot assay at 5 time points. Furthermore, we compared the course over time of the two branches of adaptive immunity to establish an eventual correlation between adaptive responses. Lastly, we evaluated putative influencing factors collected by an anonymized survey administered to all participants through multiparametric analysis. Among 984 healthcare workers evaluated for humoral immunity, 107 individuals were further analyzed to describe SARS-CoV-2-specific T-cell responses. Participants were divided into 4 age groups: <40 and ≥40 years for men, <48 and ≥48 years for women. Furthermore, results were segregated according to SARS-CoV-2-specific serostatus at baseline. The disaggregated evaluation of humoral responses highlighted antibody levels decreased in older subjects. The humoral responses were higher in females than in males (p=0.002) and previously virus-exposed subjects compared to naïve subjects (p<0.001). The vaccination induced a robust SARS-CoV-2 specific T-cell response at early time points in seronegative subjects compared to baseline levels (p<0.0001). However, a contraction was observed 6 months after vaccination in this group (p<0.01). On the other hand, the pre-existing specific T-cell response detected in natural seropositive individuals was longer-lasting than the response of the seronegative subjects, decreasing only 10 months after vaccination. Our data suggest that T-cell reactiveness is poorly impacted by sex and age. Of note, SARS-CoV-2-specific T-cell response was not correlated to the humoral response at any time point. These findings suggest prospects for rescheduling vaccination strategies by considering individual immunization status, personal characteristics, and the appropriate laboratory tests to portray immunity against SARS-CoV-2 accurately. Deepening our knowledge about T and B cell dynamics might optimize the decision-making process in vaccination campaigns, tailoring it to each specific immune response.

Predictors of Recurrent Laboratory-Confirmed Symptomatic SARS-CoV-2 Infections in a Cohort of Healthcare Workers

Repeated SARS-CoV-2 infections are plausible and related published data are scarce. We aimed to identify factors associated with the risk of recurrent (three episodes) laboratory-confirmed symptomatic SARS-CoV-2 infections. A retrospective cohort study was conducted, and 1,700 healthcare workers were enrolled. We used risk ratios (RR) and 95% confidence intervals (CI) to evaluate the factors associated with symptomatic SARS-CoV-2 infections. We identified 14 participants with recurrent illness episodes. Therefore, the incidence rate was 8.5 per 10,000 person months. In a multiple-model study, vaccinated adults (vs. unvaccinated, RR = 1.05 [1.03-1.06]) and those with a severe first illness episode (vs. mild disease, RR = 1.05 [1.01-1.10]) were at increased risk for repeated symptomatic SARS-CoV-2 reinfections. Increasing age showed a protective effect (per each additional year of age: RR = 0.98 [0.97-0.99]). Our results suggest that recurrent SARS-CoV-2 infections are rare events in adults, and they seem to be determined, partially, by vaccination status and age.