COVID-19 vaccines are designed to generate an immune response to protect against the SARS-CoV-2 virus. An effective immune response will lead to the creation of antibodies. If present, antibodies should provide some level of immune protection in the event of exposure to the virus. Immunity is not guaranteed, but can provide reassurance of the effectiveness of the vaccine.
We offer two antibody tests, both accessible via venous sample (GP-led). The VirTus test is available via capillary sample (fingerprick).
The Virtus test is based on the spike protein (S1) of the SARS CoV-2 virus. This antigen is the basis for the 3 main vaccines (Pfizer/BioNTech, Oxford/AstraZeneca, Moderna); individuals receiving these vaccines will only make antibodies to the spike protein. Traditional antibody tests (e.g., Abbott), will not detect these antibodies.
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 developed immunity to the virus.
If an individual has been infected with SARS-CoV-2 they may have detectable antibodies to both the Nucleocapsid (N) and the Receptor Binding Domain (RBD) Spike antigens. Baseline antibody tests for both N and RBD antigens are helpful to identify patients who have been previously infected with SARS-CoV-2. If an individual has been vaccinated against SARS-CoV-2, with no history of natural infection, the antibodies they develop are to the RBD Spike antigen. The test targets antibodies against the spike protein. Measuring these antibody levels could play a role in establishing vaccine efficacy and vaccine-induced immune response.