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Covid-19 Standard S1 Antibody Test

£75/kit £109/kit

This test measures how well your Covid-19 vaccines have worked or if you have previously been infected with Covid-19. The results of this test will give you clear visibility of your overall immunity to Covid-19.

  • Developed by leading professors
  • Able to measure both Covid-19 IgG and IgM antibodies
  • Fast and reliable results
  • Easy, at-home testing

Why do we test antibodies?

S1 is the Covid-19 virus protein that initially binds to your cells and allows the virus to enter these cells and cause infection. People with antibodies against the S1 protein may have protection – as their immune systems have learnt to fight back against the virus. Understanding whether you have antibodies, and getting a clear picture of how strong these antibodies are, will help you to start taking steps to feel safer and enjoy a normal life again.

How it Works

Our test will give both a numerical value for the strength of your antibody response and will also reveal whether your antibody levels are low, medium, high or very high. Repeat testing allows you to keep an eye on your antibody levels over time, which are known to drop at different rates in different people.

Why VirTus

At VirTus, our team of world-class professors in respiratory medicine have years of experience and have developed a test that provides more than just a positive or negative result. With the VirTus range of tests, you will have a much clearer picture of how strong your defence is against Covid-19.

  • Our antibody tests have been shown to have 100% accuracy in patients with high levels
  • The tests are quantitative, meaning you have visibility of the levels of antibodies in your system, as well as their strength
  • The tests measure IgG and IgM antibodies separately, giving you more detailed and accurate information about your response

Our at-home test kit allows you to measure the strength of your vaccine response quickly and easily. Get accurate results in a matter of days.


Who is the S1 test kit suitable for?

Our S1 antibody test is suitable for anyone wanting to understand their immune response to Covid-19.

What happens after I buy my test kit?

You will receive your home sample kit via Royal Mail (next working day delivery if ordered before 2pm) by free delivery. Then you will need to take your finger prick sample at home, following the instructions in the kit. 

You can then return your sample using the pre-paid envelope, which can simply go in any post box.

How long will my results take?

Results will be delivered via email (usually by 6 pm) within 2 working days of receipt of samples in VirTus’ laboratory.

What will my test kit contain?

In your finger-prick test kit, you will receive all the necessary equipment and instructions for taking the test yourself. This will include:

  • 1x detailed instruction sheet to tell you how to easily register your kit with us and how to take your sample
  • 2x blood collection tubes (we only need one tube returned with a few drops of blood; the second tube is a spare)
  • 1x pre-injection alcohol wipe
  • 3x lancets to prick your finger (one is usually enough)
  • 1x hard plastic casing to return your sample in
  • 1x biohazard bag
  • 1x plaster
  • 1x pre-paid return envelope

Does the Standard S1 test give results for other variants?

Our Standard S1 test is specific to the original Covid-19 strain. However, we also offer Omicron antibody tests and an add-on antibody test for the Delta variant.

What do my results mean?

If you receive an overall “Positive” test result, this confirms that you have either had a previous Covid-19 infection or received a Covid-19 vaccine, and you have developed an immune response against the original Covid-19 strain (first identified in Wuhan). However, you should still abide by government guidelines whenever necessary as this test does not measure your immune responses to other strains, such as Omicron

A “Negative” result means that your antibodies are below the detection limit of our test. This could be because you have not previously been infected or vaccinated against Covid-19, or you have been infected or vaccinated and your antibodies have diminished over time.


Got any questions? Email or call us on 0207 554 5855