New Delhi: After conducting its second round of testing for the novel coronavirus, the Indian Council of Medical Research (ICMR) on Tuesday concluded there was no sign of community transmission of the virus in India so far. Around 500 samples of patients admitted for respiratory illnesses between March 1-March 15 have returned negative.

Last week, the ICMR said 150 random samples, picked from Virus Research and Diagnostic Labs (VRDLs) and tested for community transmission as well, had tested negative for Covid-19.

ICMR will repeat the process of conducting tests every week across its network.

“Every week, 20 samples will be collected. This exercise was done in February and we did it for those admitted in March first week. Preliminary data shows 500 samples returned negative. The results for the rest will come tomorrow or day after,” said Dr Manoj Murhekar, Director of Chennai-based National Institute of Epidemiology. “So far we have no evidence of community outbreak.”

Community transmission is marked by infection found in a person who has not had contact with anyone who has travelled abroad and when the source of the original transmission is difficult to locate. ICMR is testing random samples of influenza and pneumonia-like illnesses to see if community spread has taken place.

ICMR Director-General Dr Balram Bhargava on Tuesday said even though India is still in stage 2 of the Covid-19 outbreak, one cannot predict when it will enter stage 3, which is when community transmission takes place.

“A majority of our patients have a history of travel or have come in direct contact with those with a travel history. We are hoping we don't have stage 3, but we cannot predict it. It depends on how strongly we close our international borders. We have stopped travel to and from Europe, much of middle-east and also other countries,” he said.