Rapid antibody test versus RT-PCR test
Rapid antibody tests* look for the presence of antibodies produced by the body to fight a virus, unlike RT-PCR test that looks for the virus itself. It can be done on blood/serum or plasma samples.
The test is vital as it helps detect previous infections in people who had a few or no symptoms and to establish whether community transmission has indeed occurred.
How is rapid test done in Kerala
The state received 10,000 kits from ICMR. Of these, six districts -- Palakkad, Kannur, Kasaragod, Malappuram, Thrissur and Thiruvananthapuram -- were given 1,000 kits each. 500 kits each were given to other districts.
Test outcome
In Kerala, rapid antibody testing has been mulled over as part of sentinel surveillance against COVID-19. However, the first round report of sentinel surveillance stated that the unavailability of antibody testing kits forced health authorities to use RT-PCR tests.
The first round which covered a period from April 19 and May 16 had ruled out community transmission as, out of the 4,400 samples analysed, only four turned positive. Upon availability of rapid antibody testing kits, the testing based on the same was started on June 8.
Categories for testing
As per a plan chalked out in this regard, the population groups were broadly divided into five groups with various sub-categories.
Healthcare workers in Covid/non-Covid settings, persons under home quarantine, vulnerable persons, police personnel, field health workers, people in contact with interstate truck drivers and migrant labourers, female sex workers, homosexuals, patients coming from the general population with acute respiratory infection with the onset within the last 10 days but not a Covid suspect, returnees from abroad, returnees from outside Kerala and persons with a travel history outside Kerala not belonging to the above categories and others.