2025.01.27

Differences Between PCR Tests, Antigen Tests, and Antibody Tests

 

Dr. Inubo’s 1-Minute Q&A

 

For those who prefer to read the video content in text form↓↓

 

PCR tests and antigen tests are both methods used to determine the presence of a virus. The advantage of PCR tests is their high sensitivity; for example, they can detect as few as six virus particles in a sample taken from the throat, nose, or saliva.

 

Antigen tests, on the other hand, are simpler and yield results quickly. However, they require a certain amount of virus in the sample to detect its presence, making them less sensitive than PCR tests.

 

Both methods have their pros and cons, but their primary purpose is to identify whether the virus is present or not. Think of PCR and antigen tests as tools to detect the existence of the virus.

 

When a virus infects the body, the immune system responds by producing antibodies. The **IgM antibody** is created during the active fight against the virus. If IgM is detected, it indicates that the virus is currently present in the body and the immune system is actively responding.

 

The **IgG antibody**, on the other hand, appears after the body has fought off the virus and developed immunity. If a test detects IgG but not IgM, it means the person was previously infected, has recovered, and now possesses immunity against the virus.

 

These are the key differences between PCR tests, antigen tests, and antibody tests.