There have been countless delays and hiccups over these past few months when it comes to coronavirus testing in the UK, both in terms of initial diagnosis and retrospective testing by means of an antibody test.
There are likely many people who experienced symptoms prior to April 2020 when widespread testing wasn’t available to the public, and who are now quite curious and anxious to confirm whether they did indeed have the virus. Although coronavirus antibody testing isn’t being conducted via the NHA and finger prick tests have been put on hold by the government, it is now possible for the public to purchase their own venous COVID19 antibody test.
What are antibody tests, do they work & where can you get one?
What Are Antibodies?
Antibodies are blood proteins produced by the body’s immune system in response to antigens as a means of fighting infections, bacteria and viruses. Antibodies are also referred to as immunoglobulins.
Am I Immune To COVID-19 If I’ve Already Had It?
As coronavirus is relatively new, not enough is known about the virus and as such there’s no confirmation as to whether you would be immune to the virus in future or for how long immunity would last if you’ve previously been infected.
Research is indicating different findings in this regard. Some suggest those with confirmed coronavirus develop low levels of antibodies that may be undetectable, while others suggest a potent immune response. Some indicate short-lasting immunity while others suggest 6 months immunity with or without antibodies.
That said, an antibody test could provide a little reassurance and allay the curiosity for those wanting to know whether they may have had the virus in the past. Discovering has an active infection, who has been infected previously and what immunity is possible are all crucial in overcoming this pandemic. Furthermore, some researchers and healthcare providers are looking for previously infected patients and plasma donors for medical studies and treatments.
Types Of Coronavirus Testing
An antibody test is different to a COVID-19 test. The diagnostic COVID-19 test looks at whether you currently have the virus. There are two types of diagnostic test: Molecular (nasal, throat or saliva) with results between 24hrs to 1 week, and antigen (nasal or throat swabs) with results up to 1hr.
Antibody testing, on the other hand, seeks to discover whether you’ve had the virus in the past based on whether your body has developed specific antibodies.
Types Of Antibody Tests
There are a few manufacturers supplying outlets with their antibody tests. These fall within two groups: Venous testing (blood taken from the vein in your arm) and finger prick testing (usually home test kits with blood samples collected from a finger prick). Finger prick kits in the UK were suspended in April 2020 following concerns raised over reliability by the regulating body, MHRA.
Two particular companies have hit the news for their immunoassay antibody test: Roche and Abbott.
How Does A Coronavirus Antibody Test Work?
Antibody tests look for antibodies in the blood, which can typically occur 1 to 3 weeks following infection. A positive result suggests you’ve developed antibodies and as such have previously had the virus.
The test examines the binding of antibodies to antigens (the viral proteins). There are a few platforms with which to do this, including chemiluminescent immunoassay, lateral flow assay, and enzyme-linked immunosorbent assay (ELISA test).
There is a possibility of false negatives and false positives with such tests. One potential issue is the timing of the test. As antibodies can take several weeks to develop, it’s typically recommended to wait a few weeks post infection prior to having an antibody test. Rates of accuracy may vary depending on the manufacturer and best results depend upon efficient sample collection.
Where Can You Buy An Antibody Test?
Antibody tests are now available online and on the high street, but it’s important to research who the test is manufactured by, where it’s being analysed and what the validity rates are. Checking that the test is CE marked (confirming with European standards) & MHRA approved are also reassuring signs. As finger prick tests are still undergoing validation by the MHRA, all tests must be done via a venous sample by a medical professional.
In May 2020, Medichecks released a Coronavirus Antibody Blood Test with finger prick and venous options. Given the restriction on the former, individuals can now order venous testing from Medichecks.
This is a CE-marked IgG test developed by the leading global healthcare and medical devices manufacturer, Abbott.
This is the newer, accredited test for quality and accuracy, with results in 3 working days. At present, no other rapid detection tests have stood up to scrutiny of validation and accuracy like this test has.
For this test, a blood sample is taken from a vein by a nurse at a registered clinic. Clinics can be found on the Medichecks website. Alternatively, you can order the kit option where a nurse will visit you at home to collect your blood sample. The sample will be sent for analysis at a UK-based UKAS-accredited laboratory.
Medichecks is popular provider of blood tests, registered with the MHRA (Medicines and Healthcare products Regulatory Agency) and with an extensive range of tests and happy customers. I was previously gifted their thyroid test kit to review and had a thoroughly positive experience, hence my confidence in recommending them as a provider.
This antibody tests makes use of chemiluminescent microparticle immunoassay (CMIA) technology. The manufacturer’s validation study detected antibodies in 100% of coronavirus cases with samples taken at least 14 days following initial symptoms. A negative result was produced in 99.6% of samples in those that didn’t have the coronavirus. This is far more reassuring than the findings from any other test thus far.
The Coronavirus Antibody test looks for immunoglobulin G (IgG) antibodies to the virus that causes the current COVID-19 illness, SARS-CoV2. The body’s immune system produces antibodies in response to the coronavirus infection and are typically detectable after 7 days from when symptoms start, increasing as time goes on. It’s thought that antibodies are detected in most who have had the infection from 14 days following symptom onset. As such, Medichecks has reported that their laboratory are finding an increase in the likelihood of detecting antibodies in tests taken 17 – 21 days after symptoms begin.
This test is a means for the general public to be tested, so an individual can see whether their immune system has developed antibodies and as such whether they have had coronavirus in the past.
Until 3rd August 2020, Medichecks are also offering 25% off all their tests here (except the covid19 antibody test).
Superdrug have also made a coronavirus antibody test available. Individuals need to call to book an appointment and register with the Superdrug Online Doctor service, before going to clinic for the blood test. This test using the TDL (The Doctors Laboratory) for analysing samples, with validation studies suggesting a 97.5% sensitivity rate and 100% specificity rate.
You can find out more about the Superdrug antibody test here.
Antibody Testing In Brief
If I were to choose, my personal choice would be Medichecks given my prior positive experiences, the validation studies conducted by Abbott and the reassurance of quality laboratory analysis. In addition, the test is convenient to order online and find a clinic. If you’re isolating or otherwise unable to travel, the nurse visit is a fantastic alternative. The Superdrug test gives us a familiar and approachable outlet to use, but less information on the test specifics is available and validation results are slightly lower than the Abbott test via Medichecks. Other providers may supply a test but leave you to source the blood draw itself, and there’s no guarantee your NHS GP will do this and as such the sampling may incur additional charges.
As this is a novel virus, there’s still not enough known as to how immunity works, such as whether someone is immune following infection or for how long. It’s important to still follow government guidelines, including the recommended hand washing and social distancing measures.
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