At Home Covid-19 (Anti-SARS-CoV-2-S Spike) IgG/IgM Total Antibody Test
This is a test for the quantitative determination of antibodies against the SARS-CoV-2 in serum. The spike protein is the target of many Covid-19 vaccines in development. This blood test enables determination of both the presence and level of antibodies to the Covid spike protein. This test can signal whether a person has already been infected and has potentially started to develop a level of immunity to the virus.
Antibody tests look for evidence of the immune response to covid-19. The aim to answer the question: have I been exposed to COVID-19 and produced an immune response? You can read in more detail about the types of test here. If you want to see if you are carrying Covid-19 now, you need to use an antigen test (PCR test).
We do not yet know if the antibodies are protective to make you immune and we do not yet know how long this immunity will last.
Testing should be undertaken 14 days or more following exposure, onset of symptoms or post-vaccination. The incubation period of COVID-19 ranges from between 1 to 14 days, with the majority of cases manifesting with symptoms at 3–5 days.
If an individual has been infected with SARS-CoV-2, they may have detectable antibodies to both the nucleocapsid (N) and the spike protein receptor binding domain (RBD). Baseline antibody tests for both nucleocapsid and RBD antigens are therefore helpful to identify patients who have been previously infected with SARS-CoV-2. It is not yet known if an individual with a positive result showing presence of IgG levels following being infected with SARS-CoV-2 will be protected, either fully or partially from future infection, or for how long protective immunity may last.
If an individual has been vaccinated against SARS-CoV-2, with no history of natural infection, the antibodies they develop are to the spike protein receptor binding domain. Determining the levels of these antibodies could play a role in establishing vaccine efficacy and vaccine-induced immune response.
The laboratory we work with offers 4 assays for the detection of antibodies targeted against SARS-CoV-2. All the tests are CE marked and registered for use in the UK. The assay we select with the laboratory by default is the Anti-SARS-CoV-2-S (Spike) IgG/IgM total antibody test. The other available assays are:
Anti-SARS-CoV-2 IgG/IgM total antibody test
This blood test enables the determination of the presence of IgG and IgM antibodies to the SARS-CoV-2 nucleocapsid protein.
SARS-CoV-2 IgG test
This blood test enables the determination of the presence of IgG antibodies to the SARS-CoV-2 nucleocapsid protein.
SARS-CoV-2 IgM test
This blood test enables the determination of the presence of IgM antibodies to the SARS-CoV-2 spike protein.
You can see a summary of the different assays below.
|
Roche Elecsys |
Roche Elecsys |
Abbott |
Abbott |
|
|---|---|---|---|---|
|
Platform |
Roche e801 |
Roche e801 |
Abbott Architect |
Abbott Architect |
|
Assay type |
Electrochemiluminescence immunoassay (ECLIA) |
Electrochemiluminescence immunoassay (ECLIA) |
Chemiluminescent Microparticle Immunoassay (CMIA) |
Chemiluminescent Microparticle Immunoassay (CMIA) |
|
Reporting format |
QUANTITATIVE |
Qualitative |
Qualitative |
Qualitative |
|
Reporting ranges |
Positive with value reported in U/ml / Negative |
Positive / Negative |
Positive / Negative |
Positive/Negative |
|
Antigen used |
Spike protein receptor binding domain (RBD) |
Nucleocapsid |
Nucleocapsid |
Spike protein |
|
Analyte target |
SARS-CoV-2 Antibodies (IgG/IgM) Total antibodies |
SARS-CoV-2 Antibodies (IgG/IgM) Total antibodies |
SARS-CoV-2 Antibodies (IgG) |
SARS-CoV-2 Antibodies (IgM) |
|
Sample type verified |
Serum – venous or capillary self-collection |
Serum – venous or capillary self-collection |
Serum – venous |
Serum – venous |
|
Sensitivity |
99.8% |
97.4% |
97.5% |
96.67% in samples taken more than 14 days post symptoms onset |
|
Specificity |
98.8% in samples taken 14 days or later after positive PCR |
100% |
99.1% |
99.0% |
|
Seasonal Corona |
24/24 Negative |
26/26 Negative |
26/26 Negative |
N/A |
Please note that the antibody tests were developed for use and have been validated on venous blood samples (blood taken from a vein by a medical professional) rather than samples of blood taken from a finger-prick. This may affect the accuracy of the test. This is why, although we recognise the convenience of a home test, we would recommend that a medical professional takes your blood sample, which can be done at home or in the clinic.
TAKING THE TEST AT HOME
Finger-prick devices are supplied in the home testing kit that is delivered safely to your address. There are clear instructions about how to obtain the blood sample included in the box. Follow the instructions carefully and then simply place the box in the prepaid envelope included and post at any postbox.
This is part of a clinical service.
Our clinical service includes a full explanation of your results which will accompany your email containing your results. Expect to obtain results within 48-72 hrs of postage.
