Amid a sharp spike in daily coronavirus cases, the union health ministry has directed all states to mandatorily re-test all symptomatic cases who came negative in rapid antigen tests. The centre has told states to ensure that no positive cases are missed to curb the spread of infection. The states have increased the use of rapid antigen testing, which is cheaper, but also have a high false negativity rate. According to government data, almost 60 per cent of all cases reported in India come from five states - Maharashtra, Andhra Pradesh, Tamil Nadu, Karnataka and Uttar Pradesh