The increase in COVID-19 cases in Tamil Nadu since Thursday has been accompanied by a marginal rise in the test positivity rate (TPR).
The fact that the TPR has been witnessing an increasing trend, albeit marginally, despite a noticeable increase in the number of tests, has highlighted the need to be alert about the possibility of a rapid increase in cases in the coming days.
While the number of people tested per day stayed at an average of around 1.42 lakh the week before, it gradually increased to 1.55 lakh on Wednesday. Since then, the TPR has increased from 1.1% to 1.3% on Sunday, accompanied by an increase in cases from 1,756 on Wednesday to 1,990 on Sunday.
A region-wise analysis showed that an increase in cases along with the tests performed was noticeable in the northern, western and delta regions (see infographic).
In the delta region, the TPR went up from 1.3% to 1.7% between Wednesday and Saturday. In the same period, the western region witnessed an increase in the TPR from 1.6% to 1.8%, and the northern region from 1% to 1.1%.
In terms of daily cases, the delta region saw a spike from 279 cases on Wednesday to 369 on Sunday. In the same period, cases reported in the western region increased from 654 to 758. Cases in the northern region increased from 651 on Wednesday to 707 on Saturday before falling to 686 on Sunday, possibly due to a drop in testing.
The southern region appeared to buck the trend, as it did not report a noticeable increase in the number of cases despite an increase in the number of tests. It was the only region to have a TPR of less than 1%.
Coimbatore, Thanjavur and Chennai were among the districts that witnessed the highest increase in cases over the past few days.
