Coronavirus cases are rising for the last 8-9 days nationally, with Delhi and Mumbai having 4-5 times more cases, a top medical expert has said on Monday."Hopefully, a sharp decline will be there in peak as we saw in South Africa when cases soared suddenly and then declined," said Dr Sandeep Nayar, HOD, Respiratory diseases BLK Hospital.India logged 1,79,723 fresh Covid cases on Monday, the most since late May, while the active cases increased to 7,23,619. With this, India's Covid-19 caseload has surged to 35.71 million.Of the 1.79 lakh new Covid cases, India reported 410 new cases of Omicron variant of coronavirus, taking the total tally of such infections to 4,033 across 27 states and UTs so far.Sikkim is the only Indian state that has not reported any case of the Omicron variant to date. As many as 146 people died due to the coronavirus infection in the past one day, taking the cumulative death toll to 4,83,936.Maharashtra recorded the maximum number of 1,216 Omicron cases, followed by Rajasthan 529, Delhi 513, Karnataka 441, Kerala 333 and Gujarat 236.The daily positivity rate was recorded at 13.29%, while the weekly positivity rate was 7.92%, according to the ministry.The number of people who have recuperated from the disease surged to 3,45,00,172, while the case fatality rate was recorded at 1.36%.The cumulative vaccine doses administered in the country so far under the nationwide Covid-19 vaccination drive have crossed 151.94 crore.India's COVID-19 tally had crossed the 20-lakh mark on August 7, 2020; 30 lakh on August 23; 40 lakh on September 5; and 50 lakh on September 16. It went past 60 lakh on September 28; 70 lakh on October 11; 80 lakh on October 29; 90 lakh on November 20; and surpassed the one-crore mark on December 19.India crossed the grim milestone of two crore infections on May 4 last year and three crore on June 23.