Using Antibody Tests for COVID-19 Beállítások

[Guest_debrahanerd_*]

This page provides a summary of guidance for clinicians and health care professionals on antibody tests. Laboratory professionals and health care professionals needing specific information on types of tests, the development of antibodies and immunity, and considerations for use in public health and clinical practice, should refer to CDC’s Interim Guidance on Antibody Testing.Antibodies are detected in the blood of people who have been previously infected with or vaccinated against a virus that causes a disease; they show the body’s efforts (past infection) or preparedness (past infection or vaccination) to fight off a specific virus. Once they are made, antibodies may protect people from getting that infection or getting severely ill for some period of time afterward. Antibodies, whether from infection or vaccination, wane (or diminish) over time. How quickly antibodies wane is different for each disease and each person.­
SARS-CoV-2, the virus that causes COVID-19, is new and what we know about it changes rapidly. This information will be updated as more data become available. Until scientists have more data on how long antibodies for COVID-19 provide protection against becoming infected with SARS-CoV-2 or severely ill with COVID-19:

[Guest_iyttruyuhj_*]

COVID-19 serology tests were generally designed early in the pandemic to detect only a few antibodies generated by natural infection, but not by vaccination. Many of the tests target antibodies not to the spike protein, but rather to the nucleocapsid protein that forms the shell enclosing the virus’ genetic material. As such, a person who has received a COVID-19 vaccine but has not been infected with SARS-CoV-2 may have a negative serology test if the test used does not detect the type of antibodies induced by the vaccine they received. In addition, it takes around two weeks for the body to generate antibodies after COVID-19 vaccination, so even tests to detect the “right” antibody could be negative in the first few weeks after vaccination. As a result, a negative serology test could be misleading by indicating that someone does not have antibodies to SARS-CoV-2 after vaccination when in fact they do or will soon. Conversely, positive serology tests after vaccination may provide a false sense of reassurance.

Viruses, like all living organisms, are composed, in part, of proteins. SARS-CoV-2, the virus that causes COVID-19, is comprised of at least 29 proteins. When a person is infected, their immune system generates antibodies to many of these different proteins. However, many vaccines trigger antibodies to only a limited number of proteins. Most COVID-19 vaccines are designed to induce antibodies only to the spike protein, a key molecule that is found on the surface of the SARS-CoV-2 virus and helps it to enter host cells and spread throughout the body.