The State’s dependence on Rapid Antigen Tests (RAT) has reduced considerably with over 64% of the total 71,68,545 tests conducted till date being molecular (Reverse Transcription Polymerase Chain Reaction, or RT-PCR). RT-PCR testing is the gold standard that has negligible chances of false negativity.
While over 30% of these have been conducted in Bengaluru Urban and Kalaburagi alone, Dakshina Kannada and Mysuru have contributed to nearly 4%. Kodagu has done the least number of RT-PCR tests, with its share being not more than 0.5 %.
With testing ramped up aggressively in Bengaluru Urban, the spread of the virus is slowing down here. However, the other districts are seeing a surge and the days taken to double COVID-19 cases in at least 13 districts is lower than the State average of 46 days.
Jawaid Akhtar, Additional Chief Secretary, Health and Family Welfare, told The Hindu that the State had set a target of conducting 80% of the total tests through the RT-PCR method, and on a day-on-day basis the target had been met in the past few days. “Although we have ramped up RT-PCR, we will continue testing using RAT as it is the most useful point-of-care test, especially in the identification and treatment of SARI and ILI cases. Our strategy of increasing tests even as the cases were surging has helped in containing the spread,” he said.
“Till a few days ago, we were conducting about 80% RAT and 20% RT-PCR tests. We have reversed this now and have overtaken Tamil Nadu in the number of RT-PCR tests,” he said.
Testing strategy
Giridhara R. Babu, member of the State’s COVID-19 Technical Advisory Committee, said, “The overall testing strategy is more important than the numbers.” He added that districts should be reviewed on two criteria. “Finding people by syndromic approach and testing people with symptoms is the first thing. Next, it is important to assess what is the proportion of symptomatic people who tested negative on RAT and who were then tested using RT-PCR. Many districts are going through a surge in cases. Therefore, testing levels have to be increased, depending on the stage of outbreak in the districts,” he said.
V. Ravi, senior professor and head of the Department of Neuro Virology at NIMHANS, who is part of the State’s COVID-19 expert committee, said Karnataka has been able to bring down the number of new cases and daily test positivity rate only after ramping up RT-PCR tests. “An increase in RT-PCR tests has helped in tracking, testing and identifying positive people and isolating them, reducing false negativity,” he said.
