The antibody test looks for antibodies made by the human body in response to the virus that appear days into the infection. “What is a large outbreak over a geographic area amenable to containment if not community transmission? A surveillance exercise by the ICMR had found strong evidence for community transmission in 36 districts. A day after the ICMR released its surveillance findings, a health ministry official had denied community transmission in the country. The official had earlier this week again denied community transmission.

Source: The Telegraph April 16, 2020 23:37 UTC