A total of 18 persons tested positive for COVID-19 in Tamil Nadu on Tuesday, taking the total number of active cases to 77. Of the new cases, Tiruvarur reported nine followed by Chennai (5), Tiruvallur (2), and one each in Coimbatore and Villupuram. A total of 230 samples were tested in the State. As of Monday’s data, the State’s overall test positivity rate stood at 2.3%.