What is the difference between a Covid-19 Antibody Test and an Antigen Test?
With the different Covid-19 tests currently around there is often confusion about which test does what. Terminology is often confusing for the non-medical person and understanding the difference between tests can sometimes get complicated. This is a basic guide that will help to clarify a few of the more common questions. For more information please visit the government website.
The three tests currently in use are:
The Antibody Test, which tests if you have had the Covid-19 infection. This is a blood sample test, usually done with a finger prick blood sample. Currently there is no evidence to show that if you have had the virus you will not get it again and this test is not used for any form of diagnosis.
The Virus Test, often referred to as an antigen or swab test, which tests if you are currently infected with the virus. This is done with a swab sample from your nose and throat, or sometimes a saliva sample.
The Antigen, Rapid Antigen or Lateral Flow Antigen Test, which tests if you are currently infected with the virus. This can be performed on site and gives results in 15–30 minutes with no laboratory equipment required.
With all of these tests it is important to be aware of their limitations and they should be administered by a healthcare professional. It is key to understand a false negative result, as the available tests do not currently have a 100% accuracy rate. The implications of this are that having taken the test it shows a false negative result (that means it shows you are not infected when in fact you are) you may therefore unknowingly spread the virus to other people or not seek necessary treatment yourself.
Finally, you must ensure that the test kit used is CE marked, this mark shows that the manufacturer of the kit has performed and met the minimum safety and performance requirements.