58 students of the Rajah Muthiah Medical College and 17 at IIT Madras tested Covid-19 positive.
Nearly 8,000 people - more than 2,000 by Corporation and 5,000 by police - are being fined every day. People must wear masks while venturing out, the commissioner said.
Nearly 90 per cent of those affected by Omicron have received both doses of vaccination and were asymptomatic, Ma Subramanian said.
Medicos say the treatment protocol against Omicron is same as that for other SARS-CoV-2 variants
Kodambakkam zone has the highest of 191 cases, followed by Alandur with 188 while Anna Nagar and Adyar have 169 each.
Public health experts said that vaccinating 30 percent of people will not be enough and the coverage needs to be improved
The RT-PCR test could be a major relief for Dubai-bound passengers, who were asked to undergo a rapid RT-PCR test four hours prior to departure.
The State reported 1,971 Covid-19 positive cases and 28 deaths taking the tally to 25,37,373 and toll to 33,752 on the day.
Chennai shows rapid decline in daily Covid count, records negative case growth of 7.6 percent since June 7
Chennai Corporation officials said that the vaccination drive is picking up in the story and camps are being held in hotspots.
The city has 19,184 active cases (4 percent) while a high of 4,91,462 people have been discharged after treatment, according to data by the Chennai Corporation.
The State's test positivity rate (TPR) was 11 percent. Also 16 percent of Monday's cases were from Chennai and its neighbouring districts.
The civic body is organising the sale of vegetables and fruits in mobile carts as all shops are shut this week as part of the total lockdown.
The CM said, "This infection can be contained only when people take a vow that they would not either contract this infection from others and also they would not spread this to other people."
The state's test positivity rate was 21 per cent. Thirty per cent of Thursday's cases were from Chennai and its neighbouring districts.
Since there has been a massive rise in infection, it may also have brought in immunity among some sections, says former Director of Public Health Dr. K Kolandasamy.