scholarly journals Finger stick blood test to assess post vaccination SARS-CoV-2 neutralizing antibody response against variants

Author(s):  
Rachel Lim ◽  
Hoi Lok Cheng ◽  
Jia Huan ◽  
Patthara Kongsuphol ◽  
Bhuvaneshwari D/O Shunmuganath ◽  
...  

There is clinical need for a quantifiable point-of-care (PoC) SARS-CoV-2 neutralizing antibody (nAb) test that is adaptable with the pandemics changing landscape. Here, we present a rapid and semi-quantitative nAb test that uses finger stick or venous blood to assess the nAb response of vaccinated population against wild-type, alpha, beta, gamma, and delta variant receptor binding domains. It captures a clinically relevant range of nAb levels, and effectively differentiates pre-vaccination, post 1st dose and post 2nd dose vaccination samples within 10 minutes. The data observed against alpha, beta, gamma, and delta variants agrees with published results evaluated in established serology tests. Finally, our test revealed a substantial reduction in nAb level for beta, gamma, and delta variants between early BNT162b2 vaccination group (within 3 months) and later vaccination group (post 3 months). This test is highly suited for PoC settings and provides an insightful nAb response in a post-vaccinated population.

2021 ◽  
pp. 026988112199156
Author(s):  
David Taylor ◽  
Matthew Atkins ◽  
Robert Harland ◽  
Irina Baburina ◽  
James H MacCabe ◽  
...  

Background: The use of clozapine demands regular monitoring of clozapine plasma concentrations and of white blood cell parameters. The delay between sending blood samples for analysis and receiving the results hinders clinical care. Point-of-care testing (POCT) can provide drug assay results within a few minutes. Aim: This study aimed to investigate the utility of a novel point-of-care device that can measure clozapine concentrations using capillary blood samples collected via a finger stick. Method: During a five-week period starting in June 2019 eligible patients were asked to provide a finger-stick capillary sample in addition to their usual venous blood sample. Samples were analysed by the novel point-of-care device and by the standard laboratory method. Capillary blood samples were tested by the MyCare™ Insite POCT analyser, and a quantitative measurement of clozapine concentration was provided within six minutes. Results: A total of 309 patients agreed to measurements by the two methods. Analysis revealed clozapine concentrations in venous blood as determined by the laboratory method ranged from 20 to 1310 ng/mL and by POCT from 7 to 1425 ng/mL. There was a strong positive correlation ( R = 0.89) between the results from the venous and the capillary sample methods. The slope of the association between standard assay and MyCare™ Insite was 1.0 with an intercept of –21 ng/mL, indicating minimal bias. Conclusion: Clozapine concentrations can be accurately measured at the point of care using capillary blood samples collected via a finger stick. This approach may be more acceptable than venous sampling to patients and, with almost instant results available, more useful to clinicians.


2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
I. P. L. Houben ◽  
C. J. L. Y. van Berlo ◽  
O. Bekers ◽  
E. C. Nijssen ◽  
M. B. I. Lobbes ◽  
...  

Purpose. To evaluate whether a handheld point-of-care (POC) device is able to predict and discriminate patients at potential risk of contrast-induced nephropathy (CIN) prior to iodine-based contrast media delivery. Methods and Materials. Between December 2014 and June 2016, women undergoing contrast-enhanced spectral mammography (CESM) with an iodine-based contrast agent were asked to have their risk of CIN assessed by a dedicated POC device (StatSensor CREAT) and a risk factor questionnaire based on national guidelines. Prior to contrast injection, a venous blood sample was drawn to compare the results of POC with regular laboratory testing. Results. A total of 351 patients were included; 344 were finally categorized as low risk patients by blood creatinine evaluation. Seven patients had a eGFR below 60 ml/min/1.73 m2, necessitating additional preparation prior to contrast delivery. The POC device failed to categorize six out of seven patients (86%), leading to (at that stage) unwanted contrast administration. Two patients subsequently developed CIN after 2–5 days, which was self-limiting after 30 days. Conclusion. The POC device tested was not able to reliably assess impairment of renal function in our patient cohort undergoing CESM. Consequently, we still consider classic clinical laboratory testing preferable in patients at potential risk for developing CIN.


2016 ◽  
Vol 30 (5) ◽  
pp. 490-497 ◽  
Author(s):  
Karen Bastianelli ◽  
Stacey Ledin ◽  
Jennifer Chen

Background: Device manufacturers have improved technology since studies were last published, thus warranting an updated analysis. Objective: Two point-of-care (POC) cholesterol testing devices were directly compared to a venous sample to determine device accuracy. Methods: Institutional review board (IRB)–approved study collected finger-stick blood samples analyzed by Cholestech LDX (Cholestech Corporation, Hayward, California) and CardioChek Plus (Polymer Technology Systems Inc, Indianapolis, Indiana) devices and compared to venous blood for 30 study participants. Statistical analyses were completed using StatisPro. Intraclass correlation coefficients were generated, and the average difference expected to be within the industry standards of total cholesterol (TC; ±10%), high-density lipoprotein (HDL) cholesterol (±12%), and triglycerides (TG; ±15%). Results: The POC devices produced clinically equivalent values when compared to the same patients’ samples analyzed in a reference laboratory. The average difference calculated from the actual individual paired percentage bias with the Integra analyzer: venous—TC −3.8%, HDL −6.9%, TG −1.8%; CardioChek—TC −7.8%, HDL −6.2%, TG 5.1%; and Cholestech—TC 0.5%, HDL −4.5%, TG −3.3%. The average of the actual paired percentage bias with the Roche Cobas analyzer: CardioChek—TC −4.2%, HDL 0.8%, TG 7.0% and Cholestech—TC 4.6%, HDL 2.6%, TG −1.6%. Conclusion: Both screening devices operated within industry accuracy standards.


2021 ◽  
Author(s):  
Maria E. Moeller ◽  
Frederik N. Engsig ◽  
Melanie Bade ◽  
Jeppe Fock ◽  
Pearlyn Pah ◽  
...  

ABSTRACTIntroductionPoint-of-care (POC) quantification of the antibody responses against the SARS-CoV-2 Spike protein can enable decentralized monitoring of immune responses after infection or vaccination. We evaluated a novel POC microfluidic cartridge-based device (ViroTrack Sero COVID-19 Total Ab) for quantitative detection of total antibodies against SARS-CoV-2 Spike trimeric spike protein and compared to standard laboratory chemiluminescence (CLIA) based tests.MethodsCapillary- and venous blood samples were collected from 101 individuals employed at Copenhagen University Hospital, Denmark. Antibody responses were measured on capillary-, venous whole blood, plasma and diluted plasma samples directly on the POC instrument. POC results were available within seven minutes on the microfluidic cartridge reader. Plasma samples were analysed on the DiaSorin LIAISON® XL CLIA Analyzer using LIAISON® SARS-CoV-2 IgM, LIAISON® SARS-CoV-2 S1/S2 IgG and LIAISON® SARS-CoV-2 TrimericS IgG assays. The data from the CLIA platform was used as a reference.ResultsThe Spearman rank’s correlation coefficient between ViroTrack Sero COVID-19 Total Ab and LIAISON® SARS-CoV-2 S1/S2 IgG and LIAISON® SARS-CoV-2 TrimericS IgG assays is found to be 0.86 and 0.90 respectively. ViroTrack Sero COVID-19 Total Ab furthermore showed high correlation (>0.86) among the different sample matrixes. The agreement for determination of samples >200 BAU/mL on POC and CLIA methods is estimated to be around 90%.ConclusionViroTrack Sero Covid Total Ab is a very rapid and simple-to-use POC test with high sensitivity and high correlation of the numerical results expressed in BAU/mL when compared to a commercial CLIA assay.


Author(s):  
Giuseppe Vetrugno ◽  
Daniele Ignazio La Milia ◽  
Floriana D’Ambrosio ◽  
Marcello Di Pumpo ◽  
Roberta Pastorino ◽  
...  

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.


Author(s):  
Gomathi Ramaswamy ◽  
Kashish Vohra ◽  
Kapil Yadav ◽  
Ravneet Kaur ◽  
Tripti Rai ◽  
...  

Abstract Introduction Globally around 47.4% of children and in India, 58% of children aged 6–59 months are anemic. Diagnosis of anemia in children using accurate technologies and providing adequate treatment is essential to reduce the burden of anemia. Point-of-care testing (POCT) devices is a potential option for estimation of hemoglobin in peripheral and field settings were the hematology analyzer and laboratory services are not available. Objectives To access the validity of the POCTs (invasive and non-invasive devices) for estimation of hemoglobin among children aged 6–59 months compared with hematology analyzer. Methods The study participants were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. Hemoglobin levels of the study participants were estimated in Sahli’s hemoglobinometer and invasive digital hemoglobinometers (DHs) using capillary blood samples. Hemoglobin levels in non-invasive DH were assessed from the finger/toe of the children. Hemoglobin levels measured in POCTs were compared against the venous blood hemoglobin estimated in the hematology analyzer. Results A total of 120 children were enrolled. The mean (SD) of hemoglobin (g/dl) estimated in auto-analyzer was 9.4 (1.8), Sahli’s hemoglobinometer was 9.2 (1.9), invasive DH was 9.7 (1.9), and non-invasive DH was 11.9 (1.5). Sahli’s hemoglobinometer (95.5%) and invasive DH (92.2%) had high sensitivity for the diagnosis of anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH had higher specificity (96.7%) compared with invasive DH (83.3%) and Sahli’s hemoglobinometer (70%). Invasive DH took the least time (2–3 min) for estimation of hemoglobin per participant, followed by Sahli’s (4–5 min) and non-invasive DH (5–7 min). Conclusion All three POCT devices used in this study are reasonable and feasible for estimating hemoglobin in under-5 children. Invasive DHs are potential POCT devices for diagnosis of anemia among under-5 children, while Sahli’s can be considered as a possible option, where trained and skilled technicians are available. Further research and development are required in non-invasive DH to improve accuracy. Lay summary In India, anemia is a serious public health problem, where 58% of the children aged 6–59 months are anemic. Point-of-care testing (POCT) using digital hemoglobinometers (DHs) has been recommended as one of the key interventions by the Anemia Mukt Bharat program since 2018 in India. These POCT devices are easy to use, less invasive, can be carried to field, require minimal training and results are available immediately. Therefore this study assessed the validity of POCT devices—invasive DH, non-invasive DH and Sahli’s hemoglobinometer among 6–59 months children in facility setting compared with the gold standard hematology analyzer. A total of 120 children under 6–59 months of age were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. The (mean hemoglobin in g/dl) invasive (9.7) and non-invasive DH (11.9) overestimated hemoglobin value, while Sahli’s (9.2) underestimated hemoglobin compared with hematology analyzer (9.4). Invasive DH (92.2%) and Sahli’s hemoglobinometer (95.5%) reported high ability to correctly identify those with anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH (96.73%) had higher ability to correctly identify those without the anemia compared with invasive DH (83.3%) and Sahli’s (70%).


2013 ◽  
Vol 24 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Marissa L Becker ◽  
Laura H Thompson ◽  
Carla Pindera ◽  
Natalie Bridger ◽  
Carmen Lopez ◽  
...  

BACKGROUND: Approximately 26% of Canadians living with HIV are unaware of their status. Point-of-care (POC) HIV tests have been introduced to simplify and expand HIV testing.OBJECTIVE: To evaluate the feasibility and acceptability of POC testing in an emergency department (ED) setting in Winnipeg, Manitoba.METHODS: A cross-sectional study of unselected adults presenting to the ED at the Health Sciences Centre Hospital (Winnipeg, Manitoba) was performed. Study procedures included pre- and post-test counselling, administration of the INSTI HIV-1/HIV-2 Antibody Test (bioLytical Laboratories, Canada) and a brief questionnaire. Venous blood samples were collected from participants for confirmatory testing on all reactive and indeterminate specimens.RESULTS: In total, 501 adults participated in the study. The majority of participants were younger than 40 years of age, approximately one-half (48.5%) were women and 53% self-identified as Aboriginal. Nearly one-half (49.1%) of the participants had undergone previous HIV testing, although 63% of these tests were performed more than a year earlier. A total of seven individuals tested reactive with the POC test, all of whom were confirmed positive using serological testing (1.4%) and were linked to an HIV specialist within 24 h. Nearly all of the participants (96%) reported satisfaction with the test and believed it belonged in the ED (93%).CONCLUSIONS: Of the participants tested, 1.4% tested reactive for HIV, which is significantly higher than the reported prevalence in Manitoba and in other similar studies conducted in North America. Furthermore, all individuals were linked to timely care. The present study demonstrated that this particular busy tertiary care ED is an important and feasible location for HIV POC testing.


2021 ◽  
Author(s):  
Preethi Eldi ◽  
Tamara H Cooper ◽  
Natalie A Prow ◽  
Liang Liu ◽  
Gary K Heinemann ◽  
...  

The ongoing COVID-19 pandemic perpetuated by SARS-CoV-2 variants, has highlighted the continued need for broadly protective vaccines that elicit robust and durable protection. Here, the vaccinia virus-based, replication-defective Sementis Copenhagen Vector (SCV) was used to develop a first-generation COVID-19 vaccine encoding the spike glycoprotein (SCV-S). Vaccination of mice rapidly induced polyfunctional CD8 T cells with cytotoxic activity and robust Th1-biased, spike-specific neutralizing antibodies, which are significantly increased following a second vaccination, and contained neutralizing activity against the alpha and beta variants of concern. Longitudinal studies indicated neutralizing antibody activity was maintained up to 9 months post-vaccination in both young and aging mice, with durable immune memory evident even in the presence of pre-existing vector immunity. This immunogenicity profile suggests a potential to expand protection generated by current vaccines in a heterologous boost format, and presents a solid basis for second-generation SCV-based COVID-19 vaccine candidates incorporating additional SARS-CoV-2 immunogens.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256423
Author(s):  
William M. Dickerson ◽  
Rebecca Yu ◽  
Helena U. Westergren ◽  
Jonathan Paraskos ◽  
Philipp Schatz ◽  
...  

Background Point-of-care (PoC) testing of platelet count (PLT) provides real-time data for rapid decision making. The goal of this study is to evaluate the accuracy and precision of platelet counting using a new microvolume (8 μL), absolute counting, 1.5 kg cytometry-based blood analyzer, the rHEALTH ONE (rHEALTH) in comparison with the International Society of Laboratory Hematology (ISLH) platelet method, which uses a cytometer and an impedance analyzer. Methods Inclusion eligibility were healthy adults (M/F) ages 18–80 for donation of fingerprick and venous blood samples. Samples were from a random N = 31 volunteers from a single U.S. site. Samples were serially diluted to test thrombocytopenic ranges. Interfering substances and conditions were tested, including RBC fragments, platelet fragments, cholesterol, triglycerides, lipids, anti-platelet antibodies, and temperature. Results The concordance between the rHEALTH and ISLH methods had a slope = 1.030 and R2 = 0.9684. The rHEALTH method showed a correlation between capillary and venous blood samples (slope = 0.9514 and R2 = 0.9684). Certain interferents changed platelet recovery: RBC fragments and anti-platelet antibodies with the ISLH method; platelet fragments and anti-platelet antibodies on the rHEALTH; and RBC fragments, platelets fragments, triglycerides and LDL on the clinical impedance analyzer. The rHEALTH’s precision ranged from 3.1–8.0%, and the ISLH from 1.0–10.5%. Conclusions The rHEALTH method provides similar results with the reference method and good correlation between adult capillary and venous blood samples. This demonstrates the ability of the rHEALTH to provide point-of-care assessment of normal and thrombocytopenic platelet counts from fingerprick blood with high precision and limited interferences.


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