Comparison of dried blood spots and venous blood for the detection of SARS-CoV-2 antibodies in a population of nursing home residents

In the current SARS-CoV-2 pandemic, testing for SARS-CoV-2 specific antibodies is paramount to monitor immune responses in post-authorization vaccination and sero-epidemiology studies. However, large scale and iterative serological testing by venipuncture in older persons can be challenging. Capillary blood sampled using a finger prick and collected on protein saver cards, i.e. dried blood spots (DBS), has already proven to be a promising alternative. However, elderly persons have a reduced cutaneous microvasculature, which may affect DBS-based antibody testing. Therefore, we aimed to evaluate the performance of DBS for the detection of SARS-CoV-2 antibodies in nursing homes residents. We collected venous blood and paired Whatman and EUROIMMUN DBS from nursing home residents, and from staff as a reference population. Venous blood samples were analyzed for the presence of SARS-CoV-2 IgG antibodies using the Abbot chemiluminescent microparticle immunoassay (CMIA). DBS were analyzed by the EUROIMMUN enzyme-linked immuno sorbent assay (ELISA) for SARS-CoV-2 IgG antibodies. We performed a statistical assessment to optimize the ELISA cut-off value for the DBS using the Youden's J index. A total of 273 paired DBS-serum samples were analyzed, of which 129 were positive as assessed by the reference test. The sensitivities and specificities of DBS ranged from 95% to 97.1% and from 97.1% to 98.8%, respectively, depending on population (residents or staff) or DBS card type. These results demonstrate that DBS sampling is a valid alternative to venepuncture for the detection of SARS-CoV-2 antibodies in the elderly.

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Comparison of Dried Blood Spots and Venous Blood for the Detection of SARS-CoV-2 Antibodies in a Population of Nursing Home Residents

Microbiology Spectrum ◽

10.1128/spectrum.00178-21 ◽

2021 ◽

Author(s):

Eline Meyers ◽

Stefan Heytens ◽

Asangwing Formukong ◽

Hanne Vercruysse ◽

An De Sutter ◽

...

Keyword(s):

Nursing Home ◽

General Population ◽

Large Scale ◽

Room Temperature ◽

Venous Blood ◽

Nursing Home Residents ◽

Dried Blood Spots ◽

Serological Tests ◽

Finger Prick ◽

Study Population

Since the implementation of newly developed SARS-CoV-2 vaccines in the general population, serological tests are of increasing importance. Because DBS samples can be obtained with a finger prick and can be shipped and stored at room temperature, they are optimal for use in large-scale SARS-CoV-2 serosurveillance or postauthorization vaccination studies, even in an elderly study population.

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COVID Seroprevalence, Symptoms and Mortality During the First Wave of SARS-CoV-2 in Canada

10.1101/2021.03.04.21252540 ◽

2021 ◽

Author(s):

◽

Prabhat Jha

Keyword(s):

Nursing Home ◽

Nursing Homes ◽

Nursing Home Residents ◽

High Sensitivity ◽

High Specificity ◽

The Elderly ◽

Dried Blood Spots ◽

Mortality Data ◽

Infection Prevalence ◽

Antibody Testing

Background: Efforts to stem the SARS-CoV-2 pandemic in Canada can benefit from direct understanding of the prevalence, infection fatality rates (IFRs), and information on asymptomatic infection. Methods: We surveyed a representative sample of 19,994 adult Canadians about COVID symptoms and analyzed IgG antibodies against SARS-CoV-2 from self-collected dried blood spots (DBS) in 8,967 adults. A sensitive and specific chemiluminescence ELISA detected IgG to the spike trimer. We compared seroprevalence to deaths to establish IFRs and used mortality data to estimate infection levels in nursing home residents. Results: The best estimate (high specificity) of adult seroprevalence nationally is 1.7%, but as high as 3.5% (high sensitivity) depending on assay cut-offs. The highest prevalence was in Ontario (2.4-3.9%) and in younger adults aged 18-39 years (2.5-4.4%). Based on mortality, we estimated 13-17% of nursing home residents became infected. The first viral wave infected 0.54-1.08 million adult Canadians, half of whom were <40 years old. The IFR outside nursing homes was 0.20-0.40%, but the COVID mortality rate in nursing home residents was >70 times higher than that in comparably-aged adults living in the community. Seropositivity correlated with COVID symptoms, particularly during March. Asymptomatic adults constituted about a quarter of definite seropositives, with a greater proportion in the elderly. Interpretation: Canada had relatively low infection prevalence and low IFRs in the community, but not in nursing homes, during the first viral wave. Self-collected DBS for antibody testing is a practicable strategy to monitor the ongoing second viral wave and, eventually, vaccine-induced immunity among Canadian adults.

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Newborn dried blood spots for serological surveys of COVID-19

10.1101/2020.08.14.20175299 ◽

2020 ◽

Author(s):

Feimei Liu ◽

Mytien Nguyen ◽

Pavithra Vijayakumar ◽

Alanna Kaplan ◽

Amit Meir ◽

...

Keyword(s):

Large Scale ◽

Dried Blood Spots ◽

Igg Antibodies ◽

Blood Spots

As COVID-19 continues to spread across the globe, the need for inexpensive, large-scale prevalence surveillance testing increases. We present a method for testing newborn dried blood spots (DBS) for anti-SARS-COV-2 IgG antibodies, and demonstrate its applicability as an easily accessible proxy for measuring maternal seroprevalence.

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Validation of whole genome sequencing from dried blood spots

BMC Medical Genomics ◽

10.1186/s12920-021-00951-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Pooja Agrawal ◽

Shanmukh Katragadda ◽

Arun K. Hariharan ◽

Vijayashree Gauribidanur Raghavendrachar ◽

Arunika Agarwal ◽

...

Keyword(s):

Whole Genome Sequencing ◽

Genome Sequencing ◽

Copy Number ◽

Large Scale ◽

Venous Blood ◽

Dried Blood Spots ◽

Whole Genome ◽

Single Nucleotide Variants ◽

Blood Spots ◽

Mitochondrial Copy Number

Abstract Background Dried blood spots (DBS) are a relatively inexpensive source of nucleic acids and are easy to collect, transport, and store in large-scale field surveys, especially in resource-limited settings. However, their performance in whole-genome sequencing (WGS) relative to that of venous blood DNA has not been analyzed for various downstream applications. Methods This study compares the WGS performance of DBS paired with venous blood samples collected from 12 subjects. Results Results of standard quality checks of coverage, base quality, and mapping quality were found to be near identical between DBS and venous blood. Concordance for single-nucleotide variants, insertions and deletions, and copy number variants was high between these two sample types. Additionally, downstream analyses typical of population-based studies were performed, such as mitochondrial heteroplasmy detection, haplotype analysis, mitochondrial copy number changes, and determination of telomere lengths. The absolute mitochondrial copy number values were higher for DBS than for venous blood, though the trend in sample-to-sample variation was similar between DBS and blood. Telomere length estimates in most DBS samples were on par with those from venous blood. Conclusion DBS samples can serve as a robust and feasible alternative to venous blood for studies requiring WGS analysis.

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Evaluation of dried blood spots as alternative sampling material for serological detection of anti-SARS-CoV-2 antibodies using established ELISAs

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2020-1436 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Heike Weisser ◽

Katja Steinhagen ◽

Ralf Höcker ◽

Viola Borchardt-Lohölter ◽

Özlem Anvari ◽

...

Keyword(s):

Large Scale ◽

Correlation Coefficients ◽

Dried Blood Spots ◽

Population Based ◽

Sample Collection ◽

Antibody Testing ◽

Serum Samples ◽

Perfect Agreement ◽

Blood Spots ◽

Paired Samples

Abstract Objectives During the current pandemic, antibody testing based on venous serum helps to determine whether the tested person has been previously infected with SARS-CoV-2. Alternatively, capillary blood can be taken via a finger prick (dried blood spots, DBS). In this study, paired DBS and venipuncture samples were tested using two serological assays to evaluate the usability of DBS for the detection of anti-SARS-CoV-2 antibodies. Methods Paired samples of DBS and venous serum were collected from 389 volunteers, of whom 75 had a recent PCR-confirmed SARS-CoV-2 infection, and tested for anti-SARS-CoV-2 IgG antibodies against both viral S1 and nucleocapsid protein (NCP) antigens using two ELISAs. Degree of agreement and correlation coefficients between ELISA results based on the two sampling methods were calculated. Results Results of DBS showed almost perfect agreement and high correlations with results from corresponding serum samples in both the S1-based ELISA and the NCP-based ELISA. Conclusions ELISA results derived from DBS showed very high agreement to those obtained with serum, supposing adequate usability and robustness of DBS as sample material for detection of anti-SARS-CoV-2 antibodies. In the near future, large-scale epidemiological screening for antibodies against SARS-CoV-2 will be carried out. Since DBS reduce the strain on healthcare institutions regarding sample collection, they have a potential to facilitate efficient community- and population-based screening in the current SARS-CoV-2 pandemic.

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Genome-Wide Profiling of RNA from Dried Blood Spots: Convergence with Bioinformatic Results Derived from Whole Venous Blood and Peripheral Blood Mononuclear Cells

Biodemography and Social Biology ◽

10.1080/19485565.2016.1185600 ◽

2016 ◽

Vol 62 (2) ◽

pp. 182-197 ◽

Cited By ~ 16

Author(s):

Thomas W. McDade ◽

Kharah M. Ross ◽

Ruby L. Fried ◽

Jesusa M. G. Arevalo ◽

Jeffrey Ma ◽

...

Keyword(s):

Peripheral Blood Mononuclear Cells ◽

Peripheral Blood ◽

Mononuclear Cells ◽

Venous Blood ◽

Dried Blood Spots ◽

Peripheral Blood Mononuclear ◽

Blood Spots ◽

Genome Wide ◽

Blood Mononuclear Cells

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Covid-19-vaccinatie en antistofbepaling bij bewoners en personeel van 2 Lanakense woonzorgcentra in de lente van 2021

Tijdschrift voor Geneeskunde ◽

10.47671/tvg.77.21.089 ◽

2021 ◽

Author(s):

F. BUNTINX ◽

I. ASNONG ◽

M. GULIKERS ◽

G. VAES ◽

H. DEWITTE ◽

...

Keyword(s):

Nursing Home ◽

Nursing Homes ◽

Vaccination Campaign ◽

Nursing Home Residents ◽

Young Female ◽

Negative Association ◽

Antibody Testing ◽

Post Vaccination ◽

Staff Members ◽

Antibody Titres

Uptake and results of Covid-19 vaccination during a pandemic in nursing home residents and staff This study involves the participation of residents and staff of 2 Flemish nursing homes in the Covid-19 vaccination program, as well as the subsequent presence and titres of Covid-19 antibodies. With 1 exception, all 259 residents and 94% of the eligible staff members (n = 237) were vaccinated, 16 young female staff members were vaccinated with some delay because of pregnancy and fertility related fears. Post-vaccination SARS-CoV-2 antibody testing was performed in 214 (83%) residents and 201 (85%) staff members. Of these, respectively 98% and 100% had SARS-CoV-2 antibodies. A clear negative association was found between antibody titres and age. Within these nursing homes (and a number of surrounding nursing homes) the vaccination campaign was successful as well as effective.

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Measurement of Glycated Hemoglobin A1c from Dried Blood by Turbidimetric Immunoassay

Journal of Diabetes Science and Technology ◽

10.1177/193229680900300527 ◽

2009 ◽

Vol 3 (5) ◽

pp. 1203-1206 ◽

Cited By ~ 23

Author(s):

Ramakrishnan Lakshmy ◽

Ruby Gupta

Keyword(s):

Whole Blood ◽

Large Scale ◽

Hemoglobin A1c ◽

Glycated Hemoglobin ◽

Intraclass Correlation ◽

Dried Blood Spots ◽

Sample Collection ◽

Blood Spots ◽

Glycated Hemoglobin A1c ◽

The Impact

Background: Glycated hemoglobin A1c (A1C) is an important marker in the diagnosis and treatment of diabetes. Dried blood measurement of A1C is useful in large scale epidemiological evaluation of A1C, especially to assess the impact of intervention programs. The possibility of using dried blood for measurement of A1C by the immunoturbidimetric method was explored in the present study. Method: Blood was collected from 30 patients, and blood spots were prepared and dried. The dried blood spot samples were kept for different lengths of time at 4°C to assess stability. Glycated hemoglobin was measured in whole blood and dried blood on the day of collection as well as on days 10 and 15 by immunoturbidimetric method. Results: The A1C values of 30 samples analyzed for comparison between whole blood estimation and dried blood ranged from 4.6% to 9.9%. The mean A1C on the day of sample collection was 6.01% ± 1.58% in fresh whole blood samples and 5.94% ± 1.58 % in dried blood spots. A linear and highly correlated relationship was observed between dried blood A1C values and those in whole blood ( r = 0.986 and intraclass correlation value = 0.993). Glycated hemoglobin values on day 10 and day 15 were comparable with the values on day 1 with a shift in mean of just 1% on day 10 and 3.04% on day 15. Conclusion: In conclusion, dried blood can be used for measurement of A1C by immunoturbidimetric method, and further stability of A1C measurement from dried blood for up to 15 days at 4°C makes it an ideal matrix for transportation in developing countries like India.

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