The Indian Council of Medical Research invited bids for an estimated 10 lakh antibody kits (for serological tests) for the diagnosis of COVID-19.
Viral infections are mainly identified by two kinds of tests– genetic and serological.
Genetic tests can identify infections that are active, but cannot be used to detect past infections. This is what serological tests seek to determine.
Unlike genetic tests, which look for RNA in swab samples, serological tests work on antibodies in blood samples. Hence, they are also called ‘antibody tests’.
To disable a pathogen, the antibody latches to a unique protein molecule on pathogen’s surface, called an antigen. Serological tests use antigen molecules to detect the presence of antibodies relevant to the infection.
Such tests are relatively inexpensive, and can display results within a few minutes.