Is there a test that can confirm that I have ever had COVID-19?

There are tests available that can confirm whether you have ever had COVID-19 by looking at the presence of specific antibodies in your blood. These tests are called serological or antibody tests.

Serology tests are designed to detect whether your body has developed antibodies to SARS-CoV-2, the virus that causes COVID-19. Antibodies are produced by the immune system in response to an infection. The most common antibodies tested are IgM, IgA, and IgG.

IgM antibodies usually appear first after an infection, within a few days to a few weeks, and indicate that you have recently been exposed to the virus. IgG antibodies appear later, usually within a few weeks of infection, and can persist in the blood for a longer period of time, indicating that you have been infected in the past. IgA antibodies can also be measured, particularly in mucous membranes such as those lining the respiratory tract.

The PCR (Polymerase Chain Reaction) test detects the genetic material of the virus and is used to diagnose an active infection. It shows that you have the virus in your system at the time of the test, but does not indicate a previous infection. The Antigen test detects viral proteins and is also used to diagnose an active infection, usually less sensitive than a PCR test.

Source: https://www.who.int/news-room/questions-and-answers/item/coronavirus-disease-covid-19-serology

Author: Prof. Dr. Dirk Devroey - Latest update: 2023-12-11 - Copyright: Clinifacts 2025