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Covid-19 Antibody Test

Want to know if you have had Covid-19?

Imperial Aesthetics are pleased to announce that they are offering rapid Covid-19 antibody tests. A small sample of blood is taken by our medical doctor via a pin prick of the index finger and results are available within 15 minutes. You will then be able to discuss your results with a member of the clinical team who will be happy to answer any questions that you may have.

 

More info about the test?

The manufacturer of the tests used across our test sites is Biopanda, the same manufacturer that is currently being offered in some NHS pharmacies. The rapid test is a qualitative lateral flow immunochromatographic assay used to detect IgG AND IgM antibodies in the blood for Covid-19.

 

How the test works?

The test assay cassette contains recombinant SARS-CoV-2 (Covid) antigen which is conjugated(bound) to coloured particles. When a blood sample is added to the test well,  any Covid-19 specific IgM and/or IgG antibodies  present within the blood will bind to the antigen, forming  antigen-antibody Coronavirus complexes, which, are visible due to the coloured conjugates. The sample then travels along a membrane within the cassette, onto which anti-human IgM and IgG have been immobilized at specific distances. The anti-human IgM/IgG capture any IgM/IgG antigen-antibody complexes that may be present, and due to the coloured particles, result in the appearance of coloured lines.

Meaning, if a blood sample contains IgM or IgG antibodies for Covid-19, a coloured line will appear in the specific region. To ensure no errors have been made in test procedure (lack of buffer or blood) a coloured line will appear in the control line region indicating that the test has been correctly carried out.

 

How accurate is the test?

Specificity (assessed via use of pre-covid pandemic samples)

  • 2% (95%CI*: 98.5% – 99.7%) *Confidence Interval

Sensitivity ( a sample was taken from 239 patients who were confirmed to be Covid-19 positive via PCR, samples were taken at varying times of onset of symptoms, as well as in asymptomatic patients)

 

Days from onset when sample was taken No. of Samples IgM Positive IgG Positive Combined Positive (Sensitivity)
Asymptomatic † 36 55.6% 44.4% 69.4% (95%CI: 51.9-83.7%)
2-10 days 106 80.2% 19.8% 81.1% (95%CI: 72.4-88.1%)
11-20 days 55 88.7% 87.1% 93.5% (95%CI: 84.3-98.2%)
21+ days 35 42.9% 100% 100% (95%CI: 90.0-100%)

† Most of these asymptomatic patients were picked up during screening, and remained asymptomatic throughout the course of their illness.

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