Tamil Nadu has come under criticism for not testing enough amid the COVID-19 pandemic. However, it appears that the state has slowly been ramping up its testing. As of April 19, the state has tested 40,876 samples belonging to 35,741 persons, making it the highest among the southern states in total tests done. However, as far as tests per million is concerned, Kerala is still ahead of Tamil Nadu, with 579.58 samples against 566.62 respectively.
In just the last two days alone, Tamil Nadu has tested 11,203 samples from 10,767 individuals for COVID-19. That’s an average of over 5,600 samples being tested.
Compare this number to a week earlier when the state had cumulatively tested only 10,655 samples on April 12. In just a week, there has been a nearly four-fold increase in testing for COVID-19.
TNM analysed data from March 9 and it shows that the state has slowly boosted its testing week on week by not only adding more testing laboratories - both government and private - but by also widening its testing criteria.
On March 9, the earliest bulletin that was available, Tamil Nadu had tested 63 samples. At the time, only one person had tested positive for the SARS-CoV-2 virus that causes the COVID-19 disease. Testing was also taking place across three centres - the King Institute of Preventive Medicine & Research in Chennai, National Institute of Virology in Pune, and Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER) in Puducherry.
A week later, testing had only increased by 55.55% with 98 samples having been tested for COVID-19 on March 16. Although the state had boosted its number of testing centres to five, the laboratories had managed to test only 10 samples from the previous day. While the state had reported only one positive case, there were a number of allegations that the state was turning away individuals who were symptomatic and had travel history. At the time, health officials told TNM that the strategy was to test the primary contacts of the lone confirmed case, while those with travel history were being quarantined.
On March 23, Tamil Nadu’s Health Department revealed that it had tested 552 samples across eight laboratories. It was a huge leap of 463% within a week. Increased testing reflected in the number of positive cases, which stood at 9 on March 23.
Days after the nationwide lockdown, Tamil Nadu increased the number of testing centres to 15. On March 30, the state had tested 2,040 samples while the number of confirmed COVID-19 cases was 67. Although the daily testing remained low, the state managed to go from testing 109 samples on March 23 to 277 samples on March 30.
In the following week, Tamil Nadu witnessed a surge of COVID-19 cases. The state went from 67 persons testing positive for the novel coronavirus on March 30 to 621 on April 6. The source of infections was traced to the Tablighi Jamaat event in New Delhi, with most patients testing positive having attended the meeting. With the state focussing on testing the Jamaat attendees, Tamil Nadu’s positive rate from samples collected soared to 12.38%. This was far higher than the national average of 4.09% on April 6. India Spend reported that Tamil Nadu had the highest percentage of positive rate from samples collected in India at the time.
By April 13, Tamil Nadu had recorded 1,173 positive cases, and also reported 11 deaths. The state had tested 12,746 samples across 25 laboratories - 16 government and 9 private centres. The increase in labs reflected in its daily testing numbers - with 2,091 samples tested on a single day. The state was testing 176.68 people per million, just marginally lower than the national average of 179.67 people per million.
Over the next six days, Tamil Nadu added six more government labs for COVID-19 testing, with 31 centres as of April 19. While there was a 220.59% increase in the overall number of samples tested from April 13, the state has also bettered the number of people tested per million population. Tamil Nadu tested 566.62 people per million compared to the national average of 331.83 people per million population.
Significantly, its positivity rate has also reduced with the increase in testing over the last few days. As of April 19, Tamil Nadu had reported 1,477 cases and 15 deaths out of 40,876 samples. The state’s rate of positive samples dropped to 3.61%. This was also lower than the national average rate of positive samples, which was 4.48%.
The fall in the rate of positive samples can perhaps be attributed to the expansion of the testing criteria. Tamil Nadu Health Minister C Vijayabaskar had told the media on April 18 that the state was testing everyone with influenza-like illness (ILI) and those with respiratory problems. This is in line with the Indian Council of Medical Research’s (ICMR) revised testing strategy for hotspots or clusters.
