COVID-19 Seroprevalence among Healthcare Workers of a Large COVID-19 Hospital in Rome Reveals Strengths and Limits of Two Different Serological Tests

Healthcare workers are at the forefront against COVID-19, worldwide. Since Fondazione Policlinico Universitario A. Gemelli (FPG) IRCCS was enlisted as a COVID-19 hospital, the healthcare workers deployed to COVID-19 wards were separated from those with limited/no exposure, whereas the administrative staff were designated to work from home. Between 4 June and 3 July 2020, an investigation was conducted to evaluate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin (IgG) antibodies among the employees of the FPG using point-of-care (POC) and venous blood tests. Sensitivity, specificity, and predictive values were determined with reverse-transcription polymerase chain reaction on nasal/oropharyngeal swabs as the diagnostic gold standard. The participants enrolled amounted to 4777. Seroprevalence was 3.66% using the POC test and 1.19% using the venous blood test, with a significant difference (p < 0.05). The POC test sensitivity and specificity were, respectively, 63.64% (95% confidence interval (CI): 62.20% to 65.04%) and 96.64% (95% CI: 96.05% to 97.13%), while those of the venous blood test were, respectively, 78.79% (95% CI: 77.58% to 79.94%) and 99.36% (95% CI: 99.07% to 99.55%). Among the low-risk populations, the POC test’s predictive values were 58.33% (positive) and 98.23% (negative), whereas those of the venous blood test were 92.86% (positive) and 98.53% (negative). According to our study, these serological tests cannot be a valid alternative to diagnose COVID-19 infection in progress.

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Accuracy of the fluorescence-aided identification technique (FIT) for detecting tooth-colored restorations utilizing different fluorescence-inducing devices: an ex vivo comparative study

Clinical Oral Investigations ◽

10.1007/s00784-021-03826-7 ◽

2021 ◽

Author(s):

W. Leontiev ◽

E. Magni ◽

C. Dettwiler ◽

C. Meller ◽

R. Weiger ◽

...

Keyword(s):

Multivariate Analysis ◽

Ex Vivo ◽

Predictive Values ◽

Composite Restorations ◽

Significant Difference ◽

Identification Technique ◽

Illumination Method ◽

Sensitivity Specificity ◽

Entire Procedure ◽

Higher Sensitivity

Abstract Objectives The aim of the present study was to compare the accuracy of the conventional illumination method (CONV) and the fluorescence-aided identification technique (FIT) for distinguishing between composite restorations and intact teeth using different fluorescence-inducing devices commonly used for FIT. Materials and methods Six groups of six dentists equipped with one of six different FIT systems each independently attempted to identify composite restorations and intact teeth on a full-mouth model with 22 composite restorations using CONV and, 1 h later, FIT. The entire procedure was repeated 1 week later. Sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values, including 95% confidence intervals (CI), were calculated for CONV and FIT overall and for each device. The influence of examiner age, method, and device on each parameter was assessed by multivariate analysis of variance. Results The sensitivity (84%, CI 81–86%), specificity (94%, CI 93–96%), PPV (92%, CI 90–94%), and NPV (90%, CI 88–91%) of FIT was significantly higher than that of CONV (47%, CI 44–50%; 82%, CI 79–84%; 66%, CI 62–69%, and 69%, CI 68–71%, respectively; p<0.001). The differences between CONV and FIT were significant for all parameters and FIT systems except VistaCam, which achieved no significant difference in specificity. Examiners younger than 40 years attained significantly higher sensitivity and negative predictive values than older examiners. Conclusions FIT is more reliable for detecting composite restorations than the conventional illumination method. Clinical relevance FIT can be considered an additional or alternative tool for improving the detection of composite restorations.

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Comparison of saliva with healthcare workers- and patient-collected swabs in the diagnosis of COVID-19 in a large cohort

BMC Infectious Diseases ◽

10.1186/s12879-021-06343-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mitnala Sasikala ◽

Yelamanchili Sadhana ◽

Ketavarapu Vijayasarathy ◽

Anand Gupta ◽

Sarala Kumari Daram ◽

...

Keyword(s):

Healthcare Workers ◽

Early Stage ◽

Cost Effective ◽

Hospitalized Patients ◽

Detection Sensitivity ◽

Nasopharyngeal Swab ◽

Predictive Values ◽

Qrt Pcr ◽

Asymptomatic Patients ◽

Sensitivity Specificity

Abstract Background A considerable amount of evidence demonstrates the potential of saliva in the diagnosis of COVID-19. Our aim was to determine the sensitivity of saliva versus swabs collected by healthcare workers (HCWs) and patients themselves to assess whether saliva detection can be offered as a cost-effective, risk-free method of SARS-CoV-2 detection. Methods This study was conducted in a hospital involving outpatients and hospitalized patients. A total of 3018 outpatients were tested. Of these, 200 qRT-PCR-confirmed SARS-CoV-2-positive patients were recruited for further study. In addition, 101 SARS-CoV-2-positive hospitalized patients with symptoms were also enrolled in the study. From outpatients, HCWs collected nasopharyngeal swabs (NPS), saliva were obtained. From inpatients, HCWs collected swabs, patient-collected swabs, and saliva were obtained. qRT-PCR was performed to detect SARS-CoV-2 by TAQPATH assay to determine the sensitivity of saliva detection. Sensitivity, specificity and positive/negative predictive values (PPV, NPV) of detecting SARS-CoV-2 were calculated using MedCalc. Results Of 3018 outpatients (asymptomatic: 2683, symptomatic: 335) tested by qRT-PCR, 200 were positive (males: 140, females: 60; aged 37.9 ± 12.8 years; (81 asymptomatic, 119 symptomatic). Of these, saliva was positive in 128 (64%); 39 of 81 asymptomatic (47%),89 of 119 symptomatic patients (74.8%). Sensitivity of detection was 60.9% (55.4–66.3%, CI 95%), with a negative predictive value of 36%(32.9–39.2%, CI 95%).Among 101 hospitalized patients (males:65, females: 36; aged 53.48 ± 15.6 years), with HCW collected NPS as comparator, sensitivity of saliva was 56.1% (47.5–64.5, CI 95%), specificity 63.5%(50.4–75.3, CI95%) with PPV of 77.2% and NPV of 39.6% and that of self-swab was 52.3%(44–60.5%, CI95%), specificity 56.6% (42.3–70.2%, CI95%) with PPV 77.2% and NPV29.7%. Comparison of positivity with the onset of symptoms revealed highest detection in saliva on day 3 after onset of symptoms. Additionally, only saliva was positive in 13 (12.8%) hospitalized patients. Conclusion Saliva which is easier to collect than nasopharyngeal swab is a viable alternate to detect SARS-COV-2 in symptomatic patients in the early stage of onset of symptoms. Although saliva is currently not recommended for screening asymptomatic patients, optimization of collection and uniform timing of sampling might improve the sensitivity enabling its use as a screening tool at community level.

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Secondary Analysis of an Electronic Surveillance System Combined with Multi-focal Interventions for Early Detection of Sepsis

Applied Clinical Informatics ◽

10.4338/aci-2016-07-ra-0112 ◽

2017 ◽

Vol 26 (01) ◽

pp. 47-66 ◽

Cited By ~ 7

Author(s):

Bonnie Westra ◽

Sean Landman ◽

Pranjul Yadav ◽

Michael Steinbach

Keyword(s):

Early Detection ◽

Surveillance System ◽

Point Of Care ◽

Management Strategies ◽

Secondary Analysis ◽

Length Of Hospital Stay ◽

Separate Analysis ◽

Electronic Surveillance ◽

Predictive Values ◽

Sensitivity Specificity

SummarySummary: To conduct an independent secondary analysis of a multi-focal intervention for early detection of sepsis that included implementation of change management strategies, electronic surveil-lance for sepsis, and evidence based point of care alerting using the POC AdvisorTM application. Methods: Propensity score matching was used to select subsets of the cohorts with balanced covariates. Bootstrapping was performed to build distributions of the measured difference in rates/ means. The effect of the sepsis intervention was evaluated for all patients, and High and Low Risk subgroups for illness severity. A separate analysis was performed patients on the intervention and non-intervention units (without the electronic surveillance). Sensitivity, specificity, and the positive predictive values were calculated to evaluate the accuracy of the alerting system for detecting sepsis or severe sepsis/ septic shock.Results: There was positive effect on the intervention units with sepsis electronic surveillance with an adjusted mortality rate of –6.6%. Mortality rates for non-intervention units also improved, but at a lower rate of –2.9%. Additional outcomes improved for patients on both intervention and non-intervention units for home discharge (7.5% vs 1.1%), total length of hospital stay (-0.9% vs –0.3%), and 30 day readmissions (-6.6% vs –1.6%). Patients on the intervention units showed better outcomes compared with non-intervention unit patients, and even more so for High Risk patients. The sensitivity was 95.2%, specificity of 82.0% and PPV of 50.6% for the electronic surveillance alerts. Conclusion: There was improvement over time across the hospital for patients on the intervention and non-intervention units with more improvement for sicker patients. Patients on intervention units with electronic surveillance have better outcomes; however, due to differences in exclusion criteria and types of units, further study is needed to draw a direct relationship between the electronic surveillance system and outcomes.

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Significance of serum-pleural effusion albumin gradient in differentiating transudative and exudative pleural effusions in comparison to light’s criteria

International Journal of Advances in Medicine ◽

10.18203/2349-3933.ijam20171041 ◽

2017 ◽

Vol 4 (2) ◽

pp. 457

Author(s):

Sujatha G. ◽

Vindhya P. ◽

Kalyan Kumar K.

Keyword(s):

Pleural Effusion ◽

Clinical Outcome ◽

Pleural Fluid ◽

Venous Blood ◽

P Value ◽

Protein Ratio ◽

Clinical Disorder ◽

Significant Difference ◽

The Difference ◽

Sensitivity Specificity

Background: Approximately one million patients develop pleural effusion every year. It is a common clinical disorder and is either a manifestation or a complication of one or other respiratory or non-respiratory disorders. It leads to serious prognosis, if not diagnosed and treated properly. To calculate SEAG and Light’s criteria and to compare SEAG with Light’s criteria in analyzing pleural effusions.Methods: A total of hundred patients were selected for the study. Pleural fluid of patients who met the inclusion and exclusion criteria were collected, when pleural fluid is being tapped for diagnostic thoracocentesis. Venous blood sample was collected along with diagnostic thoracocentesis or within 24 hours of thoracocentesis. Written informed consent was obtained from them for thoracocentesis.Results: In our study we compared the clinical outcome with outcome as per Pleural fluid/Serum protein ratio (p value of <0.0001), pleural fluid/serum LDH (p value of <0.0001) and pleural fluid LDH (p value of <0.0001) separately and the p values were statistically significant. The sensitivity, specificity, PPV and NPV of Light’s criteria were 77.2%, 100%, 100%, 93.9% respectively. We compared Light’s criteria outcome with clinical outcome and the difference was statistically significant (p value of <0.0001). SEAG showed 100% sensitivity, 97.43% specificity, 91.6% PPV and is 91.66% and NPV is 100%. We compared the clinical outcome with SEAG and there was statistically significant difference (p value of <0.0001). We compared SEAG with Light’s criteria and the difference was statistically significant (p <0.0001). We compared Light’s plus pleural fluid protein gradient with SEAG and the difference is statistically significant (p value of <0.0001).Conclusions: SEAG is more sensitive for classifying transudates and more specific for exudates than Light’s criteria.

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Comparing citrated native, kaolin-activated, and tissue factor–activated samples and determining intraindividual variability for feline thromboelastography

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638711425595 ◽

2011 ◽

Vol 23 (6) ◽

pp. 1109-1113 ◽

Cited By ~ 24

Author(s):

Amrita Banerjee ◽

Shauna L. Blois ◽

R. Darren Wood

Keyword(s):

Veterinary Medicine ◽

Tissue Factor ◽

Blood Test ◽

Jugular Vein ◽

Point Of Care ◽

Alpha Angle ◽

Maximum Amplitude ◽

Intraindividual Variability ◽

Significant Difference ◽

Kappa Value

Thromboelastography (TEG) is a point-of-care whole blood test of hemostasis. While TEG is becoming more widely used in veterinary medicine, few studies describe the use of TEG in cats. The objectives of the current study were to: 1) document the range of TEG variables produced in healthy cats using 3 sample types (citrated native, kaolin-activated, and tissue factor–activated), and 2) determine if there was a significant difference between 2 separate samples obtained from individual healthy cats on the same day. Jugular venipuncture was performed in 20 cats, and citrated blood collected for TEG. TEG analysis was performed on citrated native, kaolin-activated, and tissue factor–activated blood for each sample. Two hours later, the procedure was repeated from the opposite jugular vein, yielding a total of 120 analyses. Reaction time ( R), alpha angle (α), kappa value (κ), and maximum amplitude (MA) were recorded from each tracing. No significant differences were found between TEG tracings from the first and second venipuncture samples. Significant differences were found between sample types for R, α, κ, and MA. Means for citrated native/kaolin-activated/tissue factor–activated methods were R = 4.1/3.7/0.6 min; κ = 2.5/1.8/2.2 min; α = 59.9/65.1/70.4 degrees; MA = 47.4/49.9/44.7 mm. A limitation of this study was the small number of cats used. Thromboelastography analysis may be a suitable method of evaluating hemostasis in cats.

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Reproducibility and validity of portable haemoglobinometer for the diagnosis of anaemia in children under the age of 5 years

Journal of Nutritional Science ◽

10.1017/jns.2019.43 ◽

2020 ◽

Vol 9 ◽

Author(s):

Alessandra da Silva Pereira ◽

Inês Rugani Ribeiro de Castro ◽

Flávia Fioruci Bezerra ◽

José Firmino Nogueira Neto ◽

Ana Carolina Feldenheimer da Silva

Keyword(s):

Venous Blood ◽

Intraclass Correlation ◽

Age Groups ◽

Capillary Blood ◽

Test Method ◽

Automated System ◽

Accuracy Rate ◽

Predictive Values ◽

Sensitivity Specificity ◽

Good Agreement

Abstract Portable haemoglobinometers have been used in order to estimate the prevalence of anaemia in diverse settings. However, few studies have been conducted to evaluate their performance in children of different age groups in distinct epidemiological contexts. To evaluate the reproducibility and reliability of a portable haemoglobinometer for the diagnosis of anaemia in children <5 years Hb was measured in the venous blood of 351 children <5 years by an automated system (standard method) and in three capillary blood samples, using a portable haemoglobinometer (HemoCue®; test method). The reproducibility of the device and of the test method was evaluated using the intraclass correlation coefficient (ICC) (Hb in its continuous form), κ and prevalence-adjusted bias-adjusted κ (PABAK) (categorised variable: anaemia: yes/no). For test method validation, Bland–Altman analyses were performed and sensitivity, specificity, accuracy rate, positive predictive value (PPV) and negative predictive values (NPV) were calculated. The haemoglobinometer presented good device reproducibility (ICC = 0·79) and reasonable method reproducibility (puncture, collection and reading) (ICC = 0·71). Superficial and fair agreement (κ) and good agreement (PABAK) were observed among the diagnoses obtained through the test method. The prevalence of anaemia was 19·1 and 19·7 % using the standard and the test method, respectively, with no statistically significant differences. The test method presented higher specificity (87·7 %) and NPV (88·3 %) than sensitivity (50·7 %) and PPV (49·3 %), and intermediary accuracy rate (57·8 %). HemoCue® showed good device reproducibility and reasonable method reproducibility, as well as good performance in estimating the prevalence of anaemia. Nevertheless, it showed a fair reliability and low individual diagnostic accuracy.

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Sensitivity, Specificity and Predictive Values of Molecular and Serological Tests for COVID-19: A Longitudinal Study in Emergency Room

Diagnostics ◽

10.3390/diagnostics10090669 ◽

2020 ◽

Vol 10 (9) ◽

pp. 669 ◽

Cited By ~ 4

Author(s):

Zeno Bisoffi ◽

Elena Pomari ◽

Michela Deiana ◽

Chiara Piubelli ◽

Niccolò Ronzoni ◽

...

Keyword(s):

Emergency Room ◽

Latent Class ◽

Single Gene ◽

Molecular Test ◽

Clinical Context ◽

Serological Tests ◽

Predictive Values ◽

Molecular Tests ◽

Sensitivity Specificity

Background: We assessed the sensitivity, specificity and positive and negative predictive value (PPV and NPV) of molecular and serological tests for the diagnosis of SARS-CoV-2 infection. Methods: A total of 346 patients were enrolled in the emergency room. We evaluated three Reverse Transcriptase-real time PCRs (RT-PCRs) including six different gene targets, five serologic rapid diagnostic tests (RDT) and one ELISA. The final classification of infected/non-infected patients was performed using Latent Class Analysis combined with clinical re-assessment of incongruous cases. Results: Out of these, 24.6% of patients were classified as infected. The molecular test RQ-SARS-nCoV-2 showed the highest performance with 91.8% sensitivity, 100% specificity, 100.0% PPV and 97.4% NPV respectively. Considering the single gene targets, S and RdRp of RQ-SARS-nCoV-2 had the highest sensitivity (94.1%). The in-house RdRp presented the lowest sensitivity (62.4%). The specificity ranged from 99.2% for in-house RdRp and N2 to 95.0% for E. The PPV ranged from 97.1% of N2 to 85.4% of E and the NPV from 98.1% of S to 89.0% of in-house RdRp. All serological tests had < 50% sensitivity and low PPV and NPV. VivaDiag IgM (RDT) had 98.5% specificity, with 84.0% PPV, but 24.7% sensitivity. Conclusion: Molecular tests for SARS-CoV-2 infection showed excellent specificity, but significant differences in sensitivity. Serological tests have limited utility in a clinical context.

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Evaluation of WHO criteria to determine degree of dehydration in children with acute diarrhea

Paediatrica Indonesiana ◽

10.14238/pi45.2.2005.76-80 ◽

2016 ◽

Vol 45 (2) ◽

pp. 76

Author(s):

Suprawita Sari ◽

Supriatmo Supriatmo ◽

S L Margaretha ◽

S Nafianti ◽

B Hasibuan ◽

...

Keyword(s):

Acute Diarrhea ◽

Clinical Signs ◽

Severe Dehydration ◽

Chi Square ◽

Predictive Values ◽

Who Criteria ◽

Significant Difference ◽

Kappa Value ◽

The Difference ◽

Sensitivity Specificity

Objective To evaluate the diagnostic accuracy and agreementbetween the 1980 and 1990 WHO criteria for determining the de-gree of dehydration in children with acute diarrhea.Methods This prospective study was conducted in two hospitalsfrom October 2002 to February 2003. Clinical signs of dehydrationall patients were recorded. The degree of dehydration based onthe 1980 and 1990 WHO criteria was determined and comparedwith fluid deficit measured by the difference of body weight on ad-mission and on discharge. Chi-square test and kappa value analy-ses were performed. Sensitivity, specificity, predictive values, andaccuracy of each WHO criteria were assessed. The prevalence ofdehydration was also determined.Results Sixty-five patients, comprising 40 boys and 25 girls, werestudied. There was a significant difference between the two WHOcriteria in differentiating between dehydration and non-dehydra-tion (P<0.05). Based on the 1980 WHO criteria the prevalence ofdehydration was 62.2%. Its sensitivity, specificity, and accuracy indiagnosing dehydration were 100.0%, 55.5%, and 86.2%, respec-tively. Based on the 1990 WHO criteria, the prevalence of dehy-dration was 60.0%. Its sensitivity, specificity, and accuracy in diag-nosing dehydration were 94.9%, 46.1%, and 75.4%, respectively.There was also a significant difference between both criteria indetermining severe dehydration (P<0.05). Based on the 1980 cri-teria, the prevalence of severe dehydration was 15.4%. Its sensi-tivity, specificity, and accuracy in diagnosing severe dehydrationwere 30.0%, 94.5%, and 84.6%, respectively. Based on the 1990criteria, these results were 40.0%, 94.5%, and 86.2%, respectively.The prevalence was 15.4%. Kappa value comparing the two WHOcriteria was 0.852 in diagnosing dehydration and 0.915 in diag-nosing severe dehydration. There was no significant differencebetween the two criteria in their sensitivity and specificity (P>0.05).Conclusion Both WHO criteria can be applied to determine de-hydration in patients with acute diarrhea, although we feel that the1990 criteria is simpler

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PROKALSITONIN SEBAGAI PENANDA PEMBEDA INFEKSI BAKTERI DAN NON BAKTERI

INDONESIAN JOURNAL OF CLINICAL PATHOLOGY AND MEDICAL LABORATORY ◽

10.24293/ijcpml.v17i2.1019 ◽

2018 ◽

Vol 17 (2) ◽

pp. 76

Author(s):

Bastiana Bastiana ◽

Aryati Aryati ◽

Dominicus Husada ◽

M.Y. Probohoesodo

Keyword(s):

Bacterial Infection ◽

Roc Analysis ◽

Final Diagnosis ◽

Receiver Operating Curve ◽

Fluorescent Assay ◽

Infection Group ◽

Cross Sectional ◽

Predictive Values ◽

Significant Difference ◽

Sensitivity Specificity

Early diagnosis of an infection and prompt administration of an antibiotic can dramatically reduce morbidity and mortality.Procalcitonin (PCT), a precursor of calcitonin, has been proposed as a marker of bacterial infection. The aim of this study is to assess theefficiency of procalcitonin in children for the diagnosis of bacterial vs. non bacterial infection. This was a prospective, cross-sectional study.The subjects were enrolled consecutively, consisting of feverish children (temperature ³38.5° C) admitted to the Pediatric EmergencyDepartment with ages up to 12 years old. The subjects were divided into two groups according to their final diagnosis, bacterial and nonbacterial infection. Serum PCT concentration was measured by enzyme linked fluorescent assay (ELFA) method. Sensitivity, specificity,positive predictive and negative predictive values, and receiver operating curve (ROC) of PCT were calculated. Out of 54 patients,24 (44.4%) had a final diagnosis of bacterial infection. PCT showed a wide concentration range in the bacterial infection group (median:1.09 ng/mL, lower (L)=0.05 ng/mL, upper (U)=128.7 ng/mL) compared with non bacterial infection group (0.21 ng/mL; L=0.05ng/mL; U=12.15 ng/mL). There was a significant difference in PCT between the 2 groups (p=0.020). ROC analysis demonstrated anarea under curve (AUC) of 0.686 (95% CI, 0.534 to 0.838). Using a cut-off point of 0.5 ng/mL, the sensitivity, and specificity, positivepredictive and negative predictive values of PCT were 66.7%, 76.7%, 69.6%, 74.2%, respectively. In this study, PCT may be useful fordifferentiation of bacterial vs. non bacterial infection in children.

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Evaluation of high-throughput SARS-CoV-2 serological assays in a longitudinal cohort of mild COVID-19 patients: sensitivity, specificity and association with virus neutralization test

10.1101/2020.09.30.20194290 ◽

2020 ◽

Author(s):

Antonin Bal ◽

Bruno Pozzetto ◽

Mary-Anne Trabaud ◽

Vanessa Escuret ◽

Muriel Rabilloud ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Healthcare Workers ◽

Neutralization Test ◽

Neutralizing Antibody ◽

Virus Neutralization Test ◽

Virus Neutralization ◽

Serological Tests ◽

Course Of Disease ◽

Antibody Titers ◽

Sensitivity Specificity

BackgroundThe association between SARS-CoV-2 commercial serological assays and virus neutralization test (VNT) has been poorly explored in mild COVID-19 patients.MethodsA total of 439 serum specimens were longitudinally collected from 76 healthcare workers with RT-PCR-confirmed COVID-19. The sensitivity (determined weekly) of nine commercial serological assays were evaluated. Specificity was assessed using 69 pre-pandemic sera. Correlation, agreement and concordance with the VNT were also assessed on a subset of 170 samples. Area under the ROC curve (AUC) was estimated at several neutralizing antibody titers.ResultsThe Wantai Total Ab assay targeting the receptor binding domain (RBD) within the S protein presented the best sensitivity at different times during the course of disease. The specificity was greater than 95% for all tests except for the Euroimmun IgA assay. The overall agreement with the presence of neutralizing antibodies ranged from 62.2% (95%CI; 56.0-68.1) for bioMérieux IgM to 91.2% (87.0-94.2) for Siemens. The lowest negative percent agreement (NPA) was found with the Wantai Total Ab assay (NPA 33% (21.1-48.3)). The NPA for other total Ab or IgG assays targeting the S or the RBD was 80.7% (66.7-89.7), 90.3 (78.1-96.1) and 96.8% (86.8-99.3) for Siemens, bioMérieux IgG and DiaSorin, respectively. None of commercial assays have sufficient performance to detect a neutralizing titer of 80 (AUC<0.76).ConclusionsAlthough some assays presented a better agreement with VNT than others, the present findings emphasize that commercialized serological tests including those targeting the RBD cannot substitute a VNT for the assessment of functional antibody response.

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