Lucknow, April 5 : Lucknow has reported the highest single-day Covid-19 spike of the year with 15 new cases. With this, the number of active cases stands at 70. Previously, 17 cases were reported on October 26 last year in a single day. Among the 15 new cases, the highest came from Aliganj where four men and two women were diagnosed with infection. The positivity rate (positive samples per 100 tests) has also gone up from 0.6 to 1.1 in 15 days. Chief Medical Officer Dr Manoj Agrawal said: "We are focusing on contact tracing to nip virus transmission in the bud. For every one positive case, around 50 odd persons are being tested. People should start following Covid-19 protocols." Though no severity has been witnessed in Covid-19 cases reported in the past few days, the spike nevertheless calls for precautions. Officials have asked people to mask up when they move around in public places and avoid crowded places both indoors and outdoors. /IANS