There is no evidence of community transmission of the coronavirus infection in India as all samples collected randomly to check the spread of the Covid-19 disease have tested negative, Indian Council of Medical Research (ICMR) director-general Balram Bhargava said on Thursday.
“All random samples that we tested for severe acute respiratory infections are negative for Covid-19. This suggests there is no community transmission in India yet,” Bhargava said.
India has so far registered three deaths and 166 positive cases.
Community transmission takes place when a person tests positive for the disease but doctors are not able to trace the source of the infection. It indicates undiagnosed and often asymptomatic people are unknowingly causing infection, which makes it difficult to break the chain of transmission.
ICMR has been conducting community surveillance by lifting random samples from intensive care unit (ICU) patients suffering from severe acute respiratory infections (SARI), including severe pneumonia. These samples are taken from people with no travel history or contact with a positive patient.
Of about 1,000 samples collected since March 15, all samples have returned negative for Covid-19, Bhargava said. ICMR is expected to release the exact data later in the day.
However, a section of experts says the sample size is too small and that community transmission began in India two-three weeks ago.
According to ICMR, India is still at stage II of the disease. There are four main stages of disease outbreak. Stage I is usually when cases are imported and are not of local origin. Stage II is when there is local transmission, which means a section of people testing positive have come in contact with a positive patient having a travel history. Stage III is community transmission. Stage IV is an epidemic, when there several clusters of the infection.
“The exercise of random testing is to establish evidence of community transmission,” said Dr Nivedita Gupta, scientist, ICMR. According to Gupta,a sample returning positive would mean that the infection has found its way into the community. That would call for a change in the disease control strategy, she said.
