India, June 1 -- There is continuous demand for various types of diagnostic tests by countries all across the globe. Real-time i.e. RT-PCR test is considered gold standard frontline test for clinical diagnosis of SARS-CoV-2, causing COVID19. The test is useful only when performed in the acute stage of infection (< 7 days). For several viral infections, antibody tests are useful for disease detection after 5-7 days of illness. Understanding related to antibody tests for COVID19 is evolving and several tests are being developed globally.

IgG antibodies generally start appearing after two weeks of onset of infection, once the individual has recovered after infection and last for several months. Therefore, the IgG test is not useful for dete...