CHENNAI: The number of daily COVID-19 tests in Chennai has decreased by an average of about 3,000 after November 14.
From maintaining an average of between 10,000 to 11,000 tests a day since August, the daily tests have decreased to the 7,500 mark since last week.
In view of this, Health Secretary Dr Radhakrishan on Tuesday had written to all the district heads to ensure testing is not reduced. “Unless testing is increased to pre-festival levels, the state is
likely to miss emerging hotspots. The next 14 to 28 days are important,” he had said in his communication to district heads.
Corporation Commissioner G Prakash said the decrease is only a temporary phenomenon due to Deepavali and the numbers would be ramped up. “The testing numbers would be maintained at about 10,000,” Prakash told The New Indian Express.
While the tests have come down, the positive cases too have drastically reduced in the city since October. From recording about 1,000 cases a day, the city is now recording below 500 cases with a positivity rate of slightly above 5 percent.
‘Testing needs to be continued till at least July 2021’
Public health experts say the testing done in the city is reasonably fine for the present scenario but adequate testing must continue till July next year.
“When there are 100 cases coming a day, a minimum of 5,000 tests are required for surveillance. This margin must be maintained at least till coming July,” former director of public health Dr K Kolandasamy told The New Indian Express.
Dr Kolandasamy said a possible reason for the decrease in tests could be due to a lesser number of symptomatic cases and contacts. “When the control measures have been strong for the past eight months, the infection rate too must have become low,” he said.
Virologist Dr Jacob John said testing and daily positive cases are interrelated. “The next day's testing is dependent upon the numbers infected the previous day. Less infection may lead to less testing,”
However, Dr John pointed out that eventually the testing will have to come down. “Diabetics and those with severe symptoms may be tested,” he added.