If the recommendation by the State’s COVID-19 Technical Advisory Committee (TAC) that the lockdown should be continued till the State’s Test Positivity Rate (TPR) falls below 5% is considered, the State still has a long way to go before unlocking restrictions. As of now only two districts, Bidar and Kalaburagi, have a TPR below 5%.
Although there has been a considerable decline in the number of new cases in the last one week, the State’s average TPR for the last seven days (May 25 to May 31) is 12.79%.
What is worrisome is that the TPR in 20 districts is higher than the State average during the last seven days prior to May 31. At 32.83%, Mysuru has the highest TPR followed by 25.53% in Chikkamangaluru. While eight districts have a TPR of over 20%, 12 districts have a TPR of less than 20% but still above the State average. Six districts including Bengaluru Urban have a TPR of less than 10% with the lowest in Bidar (1.26%), and Kalaburagi (3.56%).
Sources said it will be impractical to wait till TPR falls below 5% for unlocking restrictions. “With only two districts having a TPR of less than 5% as of now, it may take at least a month for the State average TPR to further reduce from the existing 12.79%,” sources said.
Giridhara R. Babu, member of the State’s COVID-19 Technical Advisory Committee (TAC), who is also the head of Lifecourse Epidemiology at the Indian Institute of Public Health in Bengaluru, said it cannot be predicted when the TPR will reduce substantially.
“During the second wave, both the ascent and descent of TPR has been more rapid. Different districts are peaking at different times and tests should be increased considerably depending on the test positivity rate in the particular district. TPR will increase when the background prevalence is really high and the number of tests done are less,” he said.
“TPR is estimated using the formula comprising the number of positive cases in the numerator and the total number of tests done in the denominator. Test positivity will increase when the denominator is small or the numerator is high,” he explained.
C.N. Manjunath, nodal officer for labs and tests in the State’s COVID-19 task force, said as the disease cannot be uniform in all districts, graded relaxing of lockdown restrictions can be considered when the TPR is between 5% - 10% in a majority of the districts.
“Even when unlocking is considered, it should be in a graded manner with continued restrictions on public, social, and religious gatherings including marriages. Inter-district transport and travel from high-risk to low-risk districts should also be regulated depending on the positivity rate in those districts,” Dr. Manjunath said.
V. Ravi, TAC member and nodal officer for genomic confirmation of SARS-CoV-2 in Karnataka, said each district should be considered separately. “Restrictions should be relaxed in a graded manner in the districts depending on the positivity rate there,” he said.
Asserting that aggressive testing should be taken up in districts with a high prevalence, Dr. Ravi pointed out that all symptomatic positive cases and their contacts should be identified and tested.
