Community SARS-CoV-2 seroprevalence before and after the second wave of SARS-CoV-2 infection in Harare, Zimbabwe

EClinicalMedicine, Journal Year: 2021, Volume and Issue: 41, P. 101172 - 101172

Published: Oct. 25, 2021

Language: Английский

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From first to second wave: follow-up of the prospective COVID-19 cohort (KoCo19) in Munich (Germany)

BMC Infectious Diseases, Journal Year: 2021, Volume and Issue: 21(1)

Published: Sept. 8, 2021

Abstract Background In the 2nd year of COVID-19 pandemic, knowledge about dynamics infection in general population is still limited. Such information essential for health planners, as many those infected show no or only mild symptoms and thus, escape surveillance system. We therefore aimed to describe course pandemic Munich living private households from April 2020 January 2021. Methods The KoCo19 baseline study took place June including 5313 participants (age 14 years above). From November 2021, we could again measure SARS-CoV-2 antibody status 4433 (response 83%). Participants were offered a self-sampling kit take capillary blood sample (dry spot; DBS). Blood was analysed using Elecsys ® Anti-SARS-CoV-2 assay (Roche). Questionnaire on socio-demographics potential risk factors assessed at available all participants. addition, follow-up health-risk taking behaviour number personal contacts outside household (N = 2768) well leisure time activities 1263) collected summer 2020. Results Weighted adjusted (for specificity sensitivity) sero-prevalence 3.6% (95% CI 2.9–4.3%) compared 1.8% 1.3–3.4%) baseline. 91% tested positive also antibody-positive follow-up. While increased early indication geospatial clustering across city found, although cases clustered within households. Taking result into account, men age group 20–34 highest sero-positivity. sensitivity analyses, differences behaviour, partly explained these differences. Conclusion citizens with antibodies below 5% during wave pandemic. Antibodies remained present majority sero-positive Besides sex, potentially confounded by major be identified. Non-pharmaceutical public measures are thus important.

Language: Английский

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A Dried Blood Spot protocol for high-throughput quantitative analysis of SARS-CoV-2 RBD serology based on the Roche Elecsys system

Microbiology Spectrum, Journal Year: 2024, Volume and Issue: 12(4)

Published: March 1, 2024

ABSTRACT SARS-CoV-2 spreads pandemically since 2020; in 2021, effective vaccinations became available and vaccination campaigns commenced. Still, it is hard to track the spread of infection or assess success broader population. Measuring specific anti-SARS-CoV-2 antibodies most tool successful vaccinations. The need for venous-blood sampling however poses a significant barrier large studies. Dried-blood-spots on filter-cards (DBS) have been used serology our laboratory, but so far not follow quantitative anti-spike reactivity longitudinal cohort. We developed semi-automated protocol from self-sampled DBS, validating cohort matched DBS samples ( n = 825). investigated chromatographic effects, reproducibility, carry-over effects calculated positivity threshold as well conversion formula determine binding units with confidence intervals. Sensitivity specificity reached 96.63% 97.81%, respectively, compared same test performed paired venous samples. Between signal 0.018 250 U/mL, we correction formula. during vaccinations, demonstrated relative changes titers over time several individuals four follow-ups. has proven itself anti-nucleocapsid serosurveys laboratory. Similarly, high-throughput feasible complementary assay. Quantitative measurements are accurate enough titer dynamics populations also after campaigns. This work was supported by Bavarian State Ministry Science Arts; LMU University Hospital, Munich; Helmholtz Center Bonn; Bielefeld; German Education Research (proj. nr.: 01KI20271 others) Medical Biodefense Program Bundeswehr Service. Roche Diagnostics provided kits machines analyses at discounted rates. project funded European-wide Consortium ORCHESTRA. ORCHESTRA received funding European Union’s Horizon 2020 research innovation program under grant agreement No 101016167. views expressed this publication sole responsibility author, Commission responsible any use that may be made information contains. IMPORTANCE spreading globally pandemic 2020. To prevalence among populations, public health measuring induced vaccination. However, conducting large-scale studies involve challenging due associated feasibility cost issues. A more cost-efficient less invasive method serological testing using Dried-Blood-Spots filter cards (DBS). In paper, quantifying self-collected DBS. Our laboratory previously successfully antibody surveys. Likewise, an additional can sample preparation analysis. obtained levels even

Language: Английский

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Evaluation of self-collected dried blood spots for detection of SARS-CoV-2 nucleocapsid antibodies shows low sensitivity

Journal of Immunological Methods, Journal Year: 2025, Volume and Issue: 536, P. 113800 - 113800

Published: Jan. 1, 2025

Language: Английский

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Monitoring of SARS-CoV-2 antibodies using dried blood spot for at-home collection

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

Published: April 6, 2022

The utilization of vaccines to fight the spread SARS-CoV-2 has led a growing need for expansive serological testing. To address this, an EUA approved immunoassay detection antibodies in venous serum samples was investigated use with dried blood spot (DBS) samples. Results from self-collected DBS demonstrated 98.1% categorical agreement correlation (R) 0.9600 while professionally collected 100.0% 0.9888 serum. Additional studies were performed stress different aspects at-home collection, including shipping stability, effects interferences, and other sample-specific robustness studies. These at least 95.0% mean bias less than ± 20.0%. Furthermore, ability track antibody levels following vaccination BioNTech/Pfizer vaccine serial pre-dose (Day 0) out 19 weeks.

Language: Английский

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Development and Implementation of Dried Blood Spot-Based COVID-19 Serological Assays for Epidemiologic Studies

Microbiology Spectrum, Journal Year: 2022, Volume and Issue: 10(3)

Published: May 25, 2022

Serological surveillance studies of infectious diseases provide population-level estimates infection and antibody prevalence, generating crucial insight into immunity, risk factors leading to infection, effectiveness public health measures. These traditionally rely on detection pathogen-specific antibodies in samples derived from venipuncture, an expensive logistically challenging aspect serological surveillance. During the COVID-19 pandemic, guidelines implemented prevent spread SARS-CoV-2 made collection venous blood difficult at a time when serosurveillance was urgently needed. Dried spots (DBS) have generated interest as alternative for applications due their stability, low cost, ease collection; DBS can be self-generated via fingerprick by community members mailed ambient temperatures. Here, we detail development four DBS-based methods demonstrate implementation large survey 12 cities East Bay region San Francisco metropolitan area using at-home collection. We find that perform similarly plasma/serum enzyme-linked immunosorbent assays commercial assays. In addition, show reliably detect responses months postinfection track kinetics after vaccination. Implementation enabled valuable data our study population investigate changes seroprevalence over 8-month period. Our work makes strong argument studies, not just SARS-CoV-2, but any situation where phlebotomy is inaccessible. IMPORTANCE Estimation community-level or vaccination critical inform responses. Traditional invasive procedure amenable pandemic-related social-distancing are since they self-collected participants home do require refrigeration shipment storage. However, measure levels been widely utilized. comparable sampling method measured distinct The format longitudinal cohort samples, ensuring participants' safety during ongoing pandemic. demonstrates excellent measuring whenever venipuncture impractical.

Language: Английский

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Comparative performance data for multiplex SARS-CoV-2 serological assays from a large panel of dried blood spot specimens

Heliyon, Journal Year: 2022, Volume and Issue: 8(9), P. e10270 - e10270

Published: Aug. 28, 2022

The extent of the COVID-19 pandemic will be better understood through serosurveys and SARS-CoV-2 antibody testing. Dried blood spot (DBS) samples play a central role in large scale serosurveillance by simplifying biological specimen collection transportation, especially Canada. Direct comparative performance data on multiplex assays resulting from identical DBS are currently lacking. In our study, we aimed to provide for BioPlex 2200 IgG (Bio-Rad), V-PLEX Panel 2 (MSD), Elecsys Anti-SARS-CoV-2 (Roche) commercial assays, as well two highly scalable in-house (University Ottawa Mount Sinai Hospital protocols) assess their suitability DBS-based serosurveillance. These were evaluated against panels collected convalescent patients (

Language: Английский

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Quantifying neutralising antibody responses against SARS-CoV-2 in dried blood spots (DBS) and paired sera

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Sept. 11, 2023

Abstract The ongoing SARS-CoV-2 pandemic was initially managed by non-pharmaceutical interventions such as diagnostic testing, isolation of positive cases, physical distancing and lockdowns. advent vaccines has provided crucial protection against SARS-CoV-2. Neutralising antibody (nAb) responses are a key correlate protection, therefore measuring nAb is essential for monitoring vaccine efficacy. Fingerstick dried blood spots (DBS) ideal use in large-scale sero-surveillance because they inexpensive, offer the option self-collection can be transported stored at ambient temperatures. Such advantages also make DBS appealing to resource-limited settings potential future pandemics. In this study, sera, venous fingerstick on filter paper were measured. Samples collected from acutely infected individuals, convalescent individuals vaccinated individuals. Good agreement observed between measured eluted paired sera. Stability sera room temperature 28 days. Overall, study provides support viable sample collection method responses.

Language: Английский

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From first to second wave: follow-up of the prospective Covid-19 cohort (KoCo19) in Munich (Germany)

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2021, Volume and Issue: unknown

Published: April 29, 2021

Abstract Background In the 2 nd year of Covid-19 pandemic, knowledge about dynamics infection in general population is still limited. Such information essential for health planners, as many those infected show no or only mild symptoms and thus, escape surveillance system. We therefore aimed to describe course pandemic Munich living private households from April 2020 January 2021. Methods The KoCo19 baseline study took place June including 5313 participants (age 14 years above). From November 2021, we could again measure SARS-CoV-2 antibody status 4,433 (response 83%). Participants were offered a self-sampling kit take capillary blood sample (dry spot; DBS). Blood was analysed using Elecsys ® Anti-SARS-CoV-2 assay (Roche). Questionnaire on socio-demographics potential risk factors assessed at available all participants. addition, follow-up health-risk taking behaviour number personal contacts outside household (N=2768) well leisure time activities (N=1263) collected summer 2020. Results Weighted adjusted (for specificity sensitivity) sero-prevalence 3.6% (95% CI 2.9-4.3%) compared 1.8% 1.3-3.4%) baseline. 91% tested positive also antibody-positive follow-up. While increased early 2021 indication geospatial clustering across city found, although cases clustered within households. Taking result into account, men age group 20-34 highest sero-positivity. sensitivity analyses, differences behaviour, partly explained these differences. Conclusion citizens with antibodies below 5% during wave pandemic. Antibodies remained present majority Besides sex, potentially confounded by major be identified. Non-pharmaceutical public measures are thus important.

Language: Английский

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At-home sampling to meet geographical challenges for serological assessment of SARS-CoV-2 exposure in a rural region of northern Sweden, March to May 2021: a retrospective cohort study

Eurosurveillance, Journal Year: 2023, Volume and Issue: 28(13)

Published: March 30, 2023

BackgroundThe current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture testing is usually performed by trained staff at healthcare centres. Long travel distances to centres rural regions may introduce bias of towards relatively large communities closer access. Rural are therefore often not represented population-based data.AimThe aim this retrospective cohort study was develop implement strategy at-home region Sweden during spring 2021, evaluate its role provide equal health care inhabitants.MethodsWe developed sensitive method measure antibodies the S-protein optimised assay clinical use together capillary sampling.ResultsWe demonstrated that our ELISA gave comparable results after analysis or serum from SARS-CoV-2-experienced individuals. We stability under conditions reflected temperature humidity winter summer. By assessment samples 4,122 individuals, we could show both feasibility implementation shifted geographical spread favour areas.ConclusionImplementation enabled citizens living remote areas access centralised laboratory antibody tests. The used here enable disease control authorities get rapid information concerning immunity infectious diseases, even across vast distance.

Language: Английский

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