Our COVID-19 antibody testing service can help tell you if you've had coronavirus before and developed an antibody response. It does this by checking your blood for the presence of COVID-19 antibodies, which your body produces after infection with the virus. Results will indicate if you have previously been infected with COVID-19. As antibodies can take up to several weeks to develop post-infection, antibody tests are not suitable for diagnosing an active COVID-19 infection. Having a positive antibody test does not ensure that you are protected from becoming unwell if exposed to Covid-19, or for how long any protection may last. Research remains ongoing in this area.