Use of Quantitative Dried Blood Spots to Evaluate the Post-Vaccination Level of Neutralizing Antibodies against SARS-CoV-2

Life, Journal Year: 2021, Volume and Issue: 11(11), P. 1125 - 1125

Published: Oct. 22, 2021

To combat the COVID-19 pandemic, vaccines against SARS-CoV-2 are now given to protect populations worldwide. The level of neutralizing antibodies following vaccination will evolve with time and vary between individuals. Immunoassays quantifying immunoglobulins viral spike (S) protein in serum/plasma have been developed, but need for venous blood samples could limit frequency scale control populations. use a quantitative dried spot (DBS) that can be self-collected would simplify this monitoring. objective study was determine whether DBS device (Capitainer qDBS 10 µL) used combination an Elecsys anti-SARS-CoV-2 S immunoassay from Roche follow development persistence anti-S antibodies. This carried out through two clinical studies. first investigated 14 volunteers who received doses Comirnaty (Pfizer) vaccine. levels progression over post-vaccination were studied three months. produced varied subjects, similar trend observed. highly stimulated by second dose (×100) peaked weeks later. antibody subsequently decreased months later down 65%. proved sufficiently sensitive evaluating immune status prolonged time. cohort composed 200 random patients chemistry department Stockholm. In cohort, we had no information on previous infections or vaccination. Nevertheless, 87% subjects 0.8 U/mL, bias plasma variable, as also seen study.

Language: Английский

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Evolution of the newest diagnostic methods for COVID-19: a Chinese perspective

Journal of Zhejiang University SCIENCE B, Journal Year: 2023, Volume and Issue: 24(6), P. 463 - 484

Published: June 1, 2023

Language: Английский

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The representative COVID-19 cohort Munich (KoCo19): from the beginning of the pandemic to the Delta virus variant

BMC Infectious Diseases, Journal Year: 2023, Volume and Issue: 23(1)

Published: July 13, 2023

Population-based serological studies allow to estimate prevalence of SARS-CoV-2 infections despite a substantial number mild or asymptomatic disease courses. This became even more relevant for decision making after vaccination started. The KoCo19 cohort tracks the pandemic progress in Munich general population over two years, setting it apart Europe.Recruitment occurred during initial wave, including 5313 participants above 13 years from private households Munich. Four follow-ups were held at crucial times pandemic, with response rates least 70%. Participants filled questionnaires on socio-demographics and potential risk factors infection. From Follow-up 2, information was added. antibody status measured using Roche Elecsys® Anti-SARS-CoV-2 anti-N assay (indicating previous infection) anti-S infection and/or vaccination). allowed us distinguish between sources acquired antibodies.The estimated cumulative sero-prevalence increased 1.6% (1.1-2.1%) May 2020 14.5% (12.7-16.2%) November 2021. Underreporting respect official numbers fluctuated testing policies capacities, becoming factor than second half Simultaneously, campaign against virus percentage having antibodies, 86.8% (85.5-87.9%) developed Incidence (BTI) without (INS) differed (ratio INS/BTI 2.1, 0.7-3.6). However, higher non-vaccinated vaccinated one. Considering whole follow-up time, being born outside Germany, working high-risk job living area per inhabitant identified as infection, while other socio-demographic health-related variables not. Although we obtained significant within-household clustering cases, no further geospatial found.Vaccination coverage presenting but breakthrough contribute community spread. As underreporting stays can go undetected, so non-pharmaceutical measures are crucial, particularly highly contagious strains like Omicron.

Language: Английский

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The Prospective COVID-19 Post-Immunization Serological Cohort in Munich (KoCo-Impf): Risk Factors and Determinants of Immune Response in Healthcare Workers

Viruses, Journal Year: 2023, Volume and Issue: 15(7), P. 1574 - 1574

Published: July 18, 2023

Antibody studies analyze immune responses to SARS-CoV-2 vaccination and infection, which is crucial for selecting strategies. In the KoCo-Impf study, conducted between 16 June December 2021, 6088 participants aged 18 above from Munich were recruited monitor antibodies, particularly in healthcare workers (HCWs) at higher risk of infection. Roche Elecsys® Anti-SARS-CoV-2 assays on dried blood spots used detect prior infections (anti-Nucleocapsid antibodies) indicate combinations vaccinations/infections (anti-Spike antibodies). The anti-Spike seroprevalence was 94.7%, whereas, anti-Nucleocapsid, it only 6.9%. HCW status contact with SARS-CoV-2-positive individuals identified as infection factors, while current smoking associated reduced risk. Older age correlated anti-Nucleocapsid antibody levels, decreased response. Vaccination alone or combined led levels. Increasing time since second vaccination, advancing age, cumulative number cases affected response over but had no impact development/seropositivity. Due significantly faced by HCWs limited significant suggested that all require protection regardless individual traits.

Language: Английский

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Understanding the Omicron Variant Impact in Healthcare Workers: Insights from the Prospective COVID-19 Post-Immunization Serological Cohort in Munich (KoCo-Impf) on Risk Factors for Breakthrough and Reinfections

Viruses, Journal Year: 2024, Volume and Issue: 16(10), P. 1556 - 1556

Published: Sept. 30, 2024

This study analyzes immune responses to SARS-CoV-2 vaccination and infection, including asymptomatic cases, focusing on infection risks during the Omicron wave, particularly among high-risk healthcare workers. In KoCo-Impf study, we monitored 6088 vaccinated participants in Munich aged 18 above. From 13 May 31 July 2022, 2351 were follow-uped. Logistic regression models evaluated primary, secondary, breakthrough infections (BTIs). Roche Elecsys

Language: Английский

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Mapping of SARS-CoV-2 IgM and IgG in gingival crevicular fluid: Antibody dynamics and linkage to severity of COVID-19 in hospital inpatients

Journal of Infection, Journal Year: 2022, Volume and Issue: 85(2), P. 152 - 160

Published: June 3, 2022

•Gingival crevicular fluid forms a useful analyte for detecting SARS-CoV-2 antibody.•There are differential patterns of antibody reactivity across NP and Spike.•Higher levels in early acute phase linked to severity COVID-19. IntroductionThe use non-venous analytes has been priority public health tool the diagnosis, monitoring surveillance range pathogens. These methods, primarily based on Dried Blood Spots (DBS) Gingival Crevicular Fluid (GCF), were first developed UK have applied investigate outbreak transmission events,1Haywood B. Tedder R.S. Beebeejaun K. Balogun Mandal S. Andrews N. et al.Oral testing facilitates understanding hepatitis A virus household transmission.Epidemiol Infect. 2019; 147: e105Crossref PubMed Scopus (1) Google Scholar,2Glynn J.R. Bower H. Johnson Houlihan C.F. Montesano C. Scott J.T. al.Asymptomatic infection unrecognised Ebola disease Ebola-affected households Sierra Leone: cross-sectional study using new non-invasive assay antibodies virus.Lancet Infect Dis. 2017; 17: 645-653Abstract Full Text PDF (68) Scholar improve diagnosis infections underserved populations3Craine Parry J. O'Toole D'Arcy Lyons M. Improving blood-borne viral diagnosis; clinical audit uptake dried blood spot offered by substance misuse service.J Viral Hepat. 2009; 16: 219-222Crossref (34) Scholar,4Dodds J.P. A.M. J.V. Mercey D.E. tale three cities: persisting high HIV prevalence, risk behaviour undiagnosed community samples men who sex with men.Sex Transm 2007; 83: 392-396Crossref (54) addition trends informing impact interventions.5Bardsley Heinsbroek E. Harris R. Croxford Edmundson Hope V. al.The direct-acting antivirals C viraemia among people inject drugs England; real-world data 2011–2018.J 2021; 28: 1052-1463Crossref (3) Scholar,6Judd A. Hickman V.D. Sutton A.J. Simson G.V. Ramsay M.E. al.Twenty years selective B vaccination: is declining injecting drug users England Wales?.J 14: 584-591Crossref (19) ScholarThe ability antigen, nucleic acid detection characterisation applications answer questions infections. The shown transmit efficiently between individuals within communities,7Miller Waight P.A. N.J. McOwat Brown K.E. Höschler al.Transmission setting: prospective cohort children adults England.J 483-489Abstract (15) Scholar, 8Adam D.C. Wu P. Wong J.Y. Lau E.H.Y. Tsang T.K. Cauchemez al.Clustering superspreading potential Hong Kong.Nat Med. 2020; 26: 1714-1719Crossref (280) 9Payne Smith-Jeffcoat S.E. Nowak G. Chukwuma U. Geibe Hawkins R.J. al.SARS-CoV-2 serologic responses from sample US navy service members – USS Theodore Roosevelt, April 2020.Morb Mortal Wkly Rep. 69: 714-721Crossref 10Jeffery-Smith Dun-Campbell Janarthanan Fok Crawley-Boevey Vusirikala al.Infection London care homes reporting no cases or outbreaks COVID-19: observational study, 2020.Lancet Reg Health Eur. 3100038PubMed rapid spread attributed transmissions asymptomatic but infected individuals.10Jeffery-Smith 11Ye F. Xu Rong Z. Liu X. Deng Delivery carriers COVID-19 familial cluster.Int J 94: 133-138Abstract (138) 12Zhou Li Chen Zheng Lei dynamics patients COVID-19.Int 96: 288-290Abstract (135) 13Putallaz Senn L. Bosshard W. Büla C.J. at geriatric rehabilitation facility: silent threat loads.Geriatrics. 6 (Basel): 95Crossref 14Glenet Lebreil A.L. Heng N'Guyen Y. Meyer I. Andreoletti Asymptomatic adult outpatients identified as significant viable shedders.Sci 11: 20615Crossref (4) ease sampling self-collection allows accessible individual population-based diagnostics prevalence. convenience acceptability collection permit population prevalence studies, example school immunised self-isolating populations, providing an important mechanism generating inform policy. key role would be characterise relationship development infection, vaccination, measures subsequent rates transmission.Enzyme immunoassays formatted immunoglobulin (Ig) capture onto solid favoured analysis analytes. In this we compare application Immunoglobulin class M (IgM) G (IgG) Ig-capture assays detect against Nucleoprotein components Spike protein paired GCF sera convalescent hospitalised UK, correlate disease.Materials methodsStudy setting approvalsThe International Severe Acute Respiratory Emerging Infections Consortium (ISARIC) WHO Clinical Characterisation Protocol (CCP-UK) ongoing, recruiting inpatients 348 hospital sites England, Wales, Scotland, Northern Ireland.15Docherty A.B. Harrison E.M. Green C.A. Hardwick H.E. Pius Norman al.Semple MG, ISARIC4C Investigators. Features 20 133 ISARIC characteristics protocol: study.BMJ. 369: m1985Crossref (1574) Ethics approval was granted South Central—Oxford Research Committee (13/SC/0149), Scotland (20/SS/0028), Review (RPC571 RPC572; 2013). protocol further details available https://isaric4c.net/protocols/.15Docherty ScholarStudy participantsRecruitment procedures CCP-UK described previously.15Docherty Briefly, baseline demographic information including patient characteristics, symptom onset dates, illness severity, level respiratory support, COVID-19-specific treatment outcome recorded case report REDCap database. Samples included collected March 2020 June 115 five hospitals. breakdown numbers hospitals 1 5 follows n = 53, 15, 8, 24 respectively. With consent, biological samples, sera, recruited days 1, 3, 9 28 post-enrolment. all four time-points not due prioritisation delivery over research activity later discharge death. Only matched serum analysis. Patients missing date excluded. Collated analysed overall presented.Patients grouped into categories peak World Organization (WHO) ordinal scale16WHO R&D Blueprint. Novel Coronavirus, Therapeutuc Trial Synopsis. February 18, 2020. Available at:https://cdn.who.int/media/docs/default-source/blue-print/covid-19-therapeutic-trial-synopsis.pdf?sfvrsn=44b83344_1&download=true. Accessed 2022Google Scholar: (i) oxygen requirement (WHO score 3); (ii) requiring face mask nasal prongs 4); (iii) high-flow (HFNO) ventilation (NIV) 5); (iv) mechanical 6/7) (v) died admission 8).Collection extraction gingival (GCF) oracoltm swabsGingival staff brushing Oracol™ S14 foam swabs (Malvern Medical Developments, Worcester, UK) along upper lower gumlines, ie junction teeth gum, both sides patient's mouth total two minutes. then frozen −20 °C. On receipt laboratory, extracted swab adding ml elution buffer (Phosphate buffered saline containing 10% Foetal Calf Serum, 0.1% Tween-20, 0.5 µg/ml Fungizone 250 Gentamicin). moved through squeezing agitating tube wall approximately 30 s. placed directly open cap replaced tube. centrifuged 2000 rpm minutes, removed discarded. eluted transferred 2 Sarstedt™ stored °C prior testing.S1, IgM IgG ELISAsImmunoglobulin established targets: S1, whole NP. Horseradish peroxidase (HRP) conjugated full length Glycoprotein (amino acids 1–1211; His-tag) 1–149; purchased Native Antigen Company (Kidlington, Oxford, UK). S1 antigen 1–530, C-terminal twin Strep tags)17Rosa Pye V.E. Graham Muir Seow Ng K.W. can recruit heme metabolite evade immunity.Sci Adv. 7: eabg7607Crossref (39) produced gifted Francis Crick Institute HRP Bio-Rad LYNX conjugation kit, accordance manufacturer's instructions. All recombinant proteins original Victoria lineage.Solid-phase wells (NUNC® Immunomodule, U8 Maxisorp™ wells) coated 100μl volumes (a) Affinipure rabbit anti-human ɣ (Jackson ImmunoResearch, Ely, Cambridgeshire μg/ml (b) Affinpure goat IgM, Fc5µ fragment 2.5 MicroImmune Coating Buffer ELISA preservative; (ClinTech, Guildford, overnight 2–8 °C, followed 3 h 35–37 Wells washed PBS Tween quenched Blocking Solution 3–4 37 aspirated dry 4 sealed pouches desiccant until use.For these Ig ELISAs, 100 µl 1:100 dilution added well, incubated 60 ± min washing conjugate. One hundred microlitres HRP-conjugated each microwells. After incubation TMB substrate added, reaction stopped measured 450/630 nm. cut off calculated mean 4x negative controls +0.1. binding ratio (Sample/Cut Off) ≥1.0 considered reactive. specificity 98% sensitivity 79%, 75% 70% tests, respectively.18Hoschler Ijaz Ho Dicks Jegatheesan al.SARS children: oral measurements.Microbiol Spectr. 2022; 10 (Jan 5)e0078621Crossref (6) Assay validation assignment test off, correlation previously described.18Hoschler ScholarEndemic seasonal coronavirus blockingTo mitigate issues cross assay, nucleoproteins (229E, NL63, OC43 HKU1), Institute, final antigens 'cold', unconjugated, acted block non-specific reactivity, concept that flavivirus serology.19Tedder Santiago de Souza N.C. Vincente Paula Levy al.Ushiro lumb Modulated Zika NS1 conjugate offers advantages accurate specific double enzyme immunoassays.PLoS ONE. 14e0215708Crossref To demonstrate utility, individually also four-mix combination concentration tested pre-pandemic reactive unblocked assay.ResultsMatched admitted Patient Supplementary Table 1. Of patients, 34% group 27% 2, 9% 15% 4, 14% 5. As expected, differences groups noted trend females scores than males. 320 (160 160 samples) analysis.Endemic blockingSerum confirmed remained presence blocking when endemic either (Table 1). Some reduction compared False positive observed blocked 229E NL63 well where 1).Table 'Blocking' assay; OD values bold indicate samples. Each mix (samples 4) 14).SamplesNP Capture (OD)No Block229E BlockNL63 BlockOC43 BlockHKU1 BlockAll BlockSARS-CoV-2 SamplesSample 11.1840.9520.9541.0991.0350.926Sample 22.7222.1582.2112.2512.1662.075Sample 31.2121.0771.1421.1721.0641.019Sample 41.2881.2431.2821.2420.9640.981Samples pre-pandemicSample 50.2550.0750.0720.2380.2710.061Sample 60.2780.0890.0970.1570.1980.053Sample 70.2880.0740.060.1160.330.051Sample 80.2340.0590.0580.1940.1960.068Sample 90.330.0560.0510.330.3310.055Sample 100.0880.0360.0360.0330.0730.086Sample 110.0530.0370.040.0410.0570.079Sample 120.1370.1010.1020.1140.150.061Sample 130.0910.0580.0630.0670.0920.051Sample 140.0840.0440.0410.0470.1510.087 Open table tab Development inpatientsAccess 21 after allowed mapping day zero 21, rise (Fig. 1; 2) increase number 2). Differential noticeable higher proportion 14 being anti-NP displayed antigens. This indicated (IgM without IgG) detectable seven Across assays, 21–26%, 49–53%, 78–82% 15–18%, 35–43%, 56–78% 7, For 42%, 65%, 65% 67%, 87% respectively.Table 2Development proteins, spike, patients. percentage median ratios (sample OD/cut off) stages (days 0–21 post onset) >22 (range: 22–80 days).Days onsetOral FluidSerumIgMIgGIgMIgGSpikeNPS1SpikeNPS1SpikeNPS1SpikeNPS1% samples0 721.142.126.318.442.115.834.250.044.723.742.128.98 1449.365.753.035.867.243.964.265.766.750.762.751.515 2178.365.282.678.387.056.5100.095.7100.095.795.7100.0> 2256.846.865.671.887.571.884.375.090.675.090.681.2median ratios0 71.372.111.871.883.811.753.034.475.472.484.952.778 142.63.053.822.645.182.926.775.819.564.988.777.2715 214.694.508.605.519.004.8110.508.3218.3210.8716.2113.80> 221.750.753.746.4210.505.287.404.8113.9010.2813.7113.10 Antibody samplesThe week assays. Overall, more robust response tests assay. 32 days), decline antigens, decrease marked continue even 22 onset. However, although did onset; assay.Comparative good 2A). less defined comparing 2B,C), particular there notable assay.Fig. 2. X/Y plots demonstrating proteins; (A), (B) (C). Binding (BR; logged.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Antibody stratified scoreAntibody mapped symptoms 3A,C). broad distribution targets plot divided nine grids split (Low [L], Medium [M], High [H]) (Early: 0–14 days, Middle: 15–30 Late: 31–50 days). corresponding possible associations. initial majority falling representing response. suggested increased those whose (H), 3B,C). seen some suggestion association observation maintained middle (15–30 onset), reaching statistical significance instances.Fig. 3Distribution panels (IgG), period (days) (Early, Middle Late). D violin relationships earlier associated severe disease. measurement Kruskal-Wallis accounting multiple implemented.View (PPT)More limited late restricted interpretation data.Antibody samplesTesting showed broadly comparable 2; Fig. S1). Positive occur onset.DiscussionThere evolution course COVID19 pandemic encompassing formats investigating targets. Whilst serum/plasma remain gold standard detection, other DBS20Turgeon C.T. Sanders K.A. Granger D. Nett S.L. Hilgart Matern al.Detection spots.Diagn Microbiol 101115425Crossref (11) 21Marchand Roulland Semence Beck O. Ericsson Use quantitative spots evaluate post-vaccination neutralizing SARS-CoV-2.Life. 11 1125Crossref 22Beyerl Rubio-Acero Castelletti Paunovic Kroidl Khan Z.N. al.A throughput serology Roche Elecsys anti-N assay.EBioMedicine. 70103502Abstract (9) saliva23Vilela A.C.S. Costa Oliveira S.A. M.B.L.D. Fiaccadori F.S. Leles C.R. al.Validity reliability immunochromatographic IgM/IgG salivary diagnosis.Oral https://doi.org/10.1111/odi.14059Crossref (2) 24Egorov A.I. Griffin S.M. Fuzawa Kobylanski Grindstaff Padgett multiplex noninvasive its survey mail.Microbiol 9e0069321Crossref 25Chiang S.H. Tu Cheng Wei Chia al.Development quantitative, non invasive, highly sensitive specific, electrochemical anti-SARS-CoV-2 saliva.PLoS 16e0251342Crossref successfully utilised responses. invasive DBS may better suited populations such children. addition, GCF, obtained describe swabs, derived transudation plasma, saliva.The which used methods GCF.Being proportionality they affected variability quality quantity therein contained, feature various Due close homology shared coronaviruses, established. false detected alphacoronavirus (229E NL63) betacoronavirus (OC43 HKU1) unexpected epitopes common family. our investigation lineage. circulating time collected. emerging variants, consideration will need given choice additional verification needed ensure sensitivity.Mapping one levels, increasing weeks three. mirrored utility response.Differential noted. found appear earlier, classes. observations line what main analyte.26Brochot Demey Touzé Belouzard Dubuisson Schmit J.L. Anti-spike, anti-nucleocapsid neutralising individuals.Front Microbiol. 11584251Crossref (77) Brochot colleagues,26Brochot examining seroconversion, demonstrated spike proteins. Antibodies targeting receptor domain (anti-RBD) earliest anti-RBD profiles mirroring Anti-S2 lag days; subunit last detected.

Language: Английский

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Surveillance of Acute SARS-CoV-2 Infections in Elementary Schools and Daycare Facilities in Bavaria, Germany (09/2020–03/2021)

Frontiers in Pediatrics, Journal Year: 2022, Volume and Issue: 10

Published: July 6, 2022

Here we report our results of a multi-center, open cohort study ("COVID-Kids-Bavaria") investigating the distribution acute SARS-CoV-2 infections among children and staff in 99 daycare facilities 48 elementary schools Bavaria, Germany. Overall, 2,568 (1,337 school children, 1,231 preschool children) 1,288 adults (466 teachers, 822 staff) consented to participate were randomly tested three consecutive phases (September/October 2020, November/December March 2021). In total, 7,062 throat swabs analyzed for by commercial RT-PCR kits. phase I, only one worker positive. II, was detected workers, two seven children. III, no sample This corresponds positive test rate 0.05% 0.4% II 0% III. Correlation PCR result with local-7-day incidence values showed strong association 7-day-incidence more than 100/100,000 as compared <100/100,000 (OR = 10.3 [1.5-438], p < 0.005). After antibody testing offered 713 participants schools. A seroprevalence 7.7% (students) 4.5% (teachers) determined. During initial waves pandemic, risk correlated positively local 7-day incidence. Hence, occurrence reflected facilities. An increased transmission setting schooling unlikely.

Language: Английский

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Clinical sensitivity and specificity of a high-throughput microfluidic nano-immunoassay combined with capillary blood microsampling for the identification of anti-SARS-CoV-2 Spike IgG serostatus

PLoS ONE, Journal Year: 2023, Volume and Issue: 18(3), P. e0283149 - e0283149

Published: March 23, 2023

Objectives We evaluate the diagnostic performance of dried blood microsampling combined with a high-throughput microfluidic nano-immunoassay (NIA) for identification anti-SARS-CoV-2 Spike IgG seropositivity. Methods conducted serological study among 192 individuals documented prior SARS-CoV-2 infection and 44 negative individuals. Participants had long interval 11 months since their qRT-PCR positive test. Serum was obtained after venipuncture tested an automated electrochemiluminescence S total Ig reference assay, commercial ELISA anti-S1 index test NIA. In addition, 109 participants from cohort participated in capillary collection using three devices: Mitra, repurposed glucose strips, HemaXis. Samples were dried, shipped by regular mail, extracted, measured Results Using serum samples, we achieve clinical sensitivity 98·33% specificity 97·62% on NIA, affirming high NIA post infection. Combining obtain 95·05% 61·11% 83·16% HemaXis, 91·49% HemaXis extraction, without any drop specificity. Discussion High demonstrated when testing micro-volume samples which is expected to facilitate its use large-scale studies home-based sampling or collected field.

Language: Английский

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Dried blood spot eluates are suitable for testing of SARS-CoV-2 IgG antibodies targeting Spike protein 1 and Nucleocapsid protein

Biochemistry and Biophysics Reports, Journal Year: 2023, Volume and Issue: 34, P. 101479 - 101479

Published: April 25, 2023

Dried blood spots (DBS) provide easy handling and are thus a beneficial tool for data collection, e.g. epidemiological studies. The suitability of DBS the assessment antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was analyzed with regards to use in future studies addressing seroprevalence population. 121 volunteers gave venous sample capillary samples on two cards (PerkinElmer Ahlstrom-Munksjö) via self-sampling under supervision. All were using Anti-SARS-CoV-2 ELISA (IgG) NCP from EUROIMMUN performed EUROLabWorkstation ELISA. Correlation coefficients between results based different sampling methods calculated. Results analysis SARS-CoV-2 IgG S1 highly correlated serum values (r = 0.96). In addition, calculation phi coefficient showed no significant difference qualitative both (rφ 0.98-1.0). Further eluates after prolonged storage 6-8 h also high correlation 0.97 r 0.93, respectively). study indicate NCP. For eluate, stability measurement can be assumed.

Language: Английский

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Simple, sensitive, specific self-sampling assay secures SARS-CoV-2 antibody signals in sero-prevalence and post-vaccine studies

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Feb. 3, 2022

At-home sampling is key to large scale seroprevalence studies. Dried blood spot (DBS) self-sampling removes the need for medical personnel specimen collection but facilitates referral an appropriately accredited laboratory accurate sample analysis. To establish a highly sensitive and specific antibody assay that would facilitate prevalence vaccine-response Paired sera DBS eluates collected from 439 sero-positive, 382 sero-negative individuals 34 vaccine recipients were assayed by capture ELISAs IgG IgM SARS-CoV-2. combined on achieved diagnostic sensitivity of 97.9% (95%CI 96.6 99.3) specificity 99.2% (95% CI 98.4 100) compared serum, displaying limits detection equivalent 23 10 WHO IU/ml, respectively. A strong correlation (r = 0.81) was observed between serum reactivities. Reactivity remained stable with samples deliberately rendered inadequate, (p 0.234) when accidentally damaged or 'invalid'. All sero-positive. This provides secure method comparable serum. The feasibility testing in sero-prevalence studies monitoring post-vaccine responses confirmed, offering robust reliable tool serological at population level.

Language: Английский

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