States like Tamil Nadu, Assam and Punjab may see the peak of second wave of coronavirus cases in the next two weeks, the SUTRA model that charts the trajectory of COVID-19 suggests.

However, the relief is that Delhi and states like Maharashtra, Uttar Pradesh, Chhattisgarh, Gujarat, Madhya Pradesh have well passed their peak, the model further suggests.

It also says that the country reached its peak by May 4 and then the daily cases have seen downward trend. However, on May 7, the country recorded 4,14,188 cases, the single highest in any day. ''Big states like Tamil Nadu, Punjab, Himachal Pradesh, Assam are yet to see their peak,'' said Prof. M Vidyasagar of IIT-Hyderabad, one of the three scientists working on the modelling. The models suggest Tamil Nadu may see a peak by May 29-31 while Puducherry may witness a peak on May 19-20. States in east and northeast India are yet to see their peak. Assam may see a peak by May 20-21, the model suggests. On Monday, the state detected 6,394 new cases, which is also the highest on a single day. Chief minister Himanta Biswas Sarma said the state also recorded 92 more COVID-19 deaths on Monday, its highest single-day fatality. Models predicted a dip in infection in Arunachal Pradesh, Manipur and the cases in these states did record a decline but they have started increasing marginally. Meghalaya could see a peak on May 30-31, while Tripura could see a peak on May 26-27, the model suggests.

In the north, Himachal Pradesh and Punjab are witnessing a surge in the cases. Himachal Pradesh may see a peak in the cases by May 24 and Punjab by May 22. Odisha was to peak by May 16-17.

States like Maharashtra, Uttar Pradesh, Karnataka, Madhya Pradesh, Jharkhand, Rajasthan, Kerala, Sikkim, Uttarakhand, Gujarat, Haryana besides Delhi and Goa have already seen their peak. The health ministry in its press briefing on Tuesday said Maharashtra, Uttar Pradesh, Delhi, Bihar, Madhya Pradesh and Chhattisgarh have shown a decline in COVID-19 cases and a decline in positivity. It added that Maharashtra, Uttar Pradesh, Delhi, Bihar, Madhya Pradesh and Chhattisgarh have shown a decline in cases and a decline in positivity, it added.

Mathematical models help predict the intensity of coronavirus cases and policy decisions can be taken on its basis. The SUTRA model came into existence last year after the Department of Science and Technology formed a group of scientists to work on mathematical models to forecast the surge of coronavirus.

The modelling faced intense criticism after it could not predict the exact nature of the second wave.

A statement issued by the DST and signed by Vidyasagar, IIT Kanpur Professor Manindra Agrawal and deputy chief of Integrated Defence Staff Madhuri Kanitkar, said mathematical models had predicted a second wave of coronavirus and its peak in the third week of April with daily cases of 1 lakh. But the numbers were much higher than the model predicted.