ATLANTA, GA-Antibodies to SARS-CoV-2, the virus that causes COVID-19, can be detected in the blood of people who have recovered from COVID-19 or people who have been vaccinated against COVID-19. Getting a vaccine is safer than getting COVID-19, and vaccination against COVID-19 is recommended for everyone ages 5 years and older.
If someone has already had COVID-19, vaccination against COVID-19 increases their body’s antibody response, which improves their protection.
It is important to remember that some people with antibodies to SARS-CoV-2 may become infected after vaccination (vaccine breakthrough infection) or after recovering from a past infection (reinfected). Based on what we know right now, risk of reinfection is low for at least the first 6 months following an infection with the virus that causes COVID-19 diagnosed by a laboratory test. When someone who is fully vaccinated gets COVID-19, it is called a vaccine breakthrough infection. No vaccine is 100% effective, so some breakthrough infections are expected. The risk of infection, severe illness, hospitalization, and death are all much lower for vaccinated people compared to people who are unvaccinated. When reinfections or breakthrough infections happen, having antibodies plays an important role in helping prevent severe illness, hospitalization, and death.
For many diseases, including COVID-19, antibodies are expected to decrease or “wane” over time. After a long enough period of time, your level of antibodies can decrease below a level that provides effective protection. This level is called the “threshold of protection.” When antibodies decrease below the threshold of protection, you may become more vulnerable to severe illness. We do not yet know what the threshold of protection for antibodies is for the virus that causes COVID-19 or how long it takes these antibodies to wane. Even after antibodies wane, your immune system may have cells that remember the virus that can act quickly to protect you from severe illness if you become infected. These topics are being researched by scientists all over the world.
I have COVID-19 antibodies. What does it mean?
A positive antibody test result can help identify someone who has had COVID-19 in the past or has been vaccinated against COVID-19. Antibody tests are not used if you have symptoms of COVID-19 or for diagnosing a current case of COVID-19. This is because it takes most people with a healthy immune system 1 to 3 weeks after getting COVID-19 to develop antibodies. A viral test is recommended to identify a current infection with the virus that causes COVID-19. More information about the role and uses of antibody testing is available.
Most people who have a positive antibody test result can continue with normal activities, including work, but they should still take steps to protect themselves and others, including getting vaccinated.
Studies show that people who have antibodies from an infection with the virus that causes COVID-19 can improve their level of protection by getting vaccinated.
A positive antibody test result alone, especially one from an infection at an unknown time or that was determined by a viral test more than 6 months ago, does not necessarily mean that you are immune to getting COVID-19. If you have had an antibody test, it is important to review your test results with your healthcare provider.
Media Release/Centers for Disease Control and Prevention
