As confirmed COVID-19 cases crossed 3,000, Indian Council of Medical Research (ICMR) has issued an advisory to carry out rapid antibody tests on all influenza like illness cases reported from containment zones and in large migration gatherings or evacuees centres of the country. All persons having cough, cold, mild fever or sore throat from such locations will thus be subjected to rapid antibody tests.
The introduction of rapid antibody tests will allow state governments to carry out more number of tests at the facility level itself. If the antibody test is negative, individuals will normally be advised home quarantine and get the test repeated after 10 days of the previous rapid antibody test. However, the patients may also be referred to a confirmatory RT-PCR test (the standard test that is being carried out by ICMR to detect COVID-19 patients from the beginning) based on medical assessment. If the random test is positive, clinical assessment, hospital treatment and home isolation will follow.
A healthcare expert said rapid tests are not as authoritative as RT-PCR tests, but could be a tool to know if there is community transmission. "Selecting people in a meaningful way, and testing them, we can assure, if there are a significant number of antibody positives, that there is a community transmission. If not, there is no community transmission", he said.
However, if the antibody test is very sensitive, and can detect antibody against COVID-19 antigen, with high specificity, then it will become a cheaper and more easily administered test which can be done in all labs, since only a pinprick is required and no need for taking swabs and such samples, which needs expertise and more lab facilities, he added.
India has carried out over 17,000 COVID-19 tests so far using RT-PCR molecular diagnosis technology. The number of confirmed cases on April 4 is 3072, of which 2,784 cases are active.
The demand to expand the scope of testing to more people and allow rapid diagnostic tests has been coming from several states that are keen to step up their containment efforts to check the disease outbreak.