TN first state to test 10 mn — all RT-PCR


Chennai: Every morning at 8, Sugitha Munuswamy, 30, a Covid-19 sample collector walks from her home in Kannagi Nagar (a resettlement slum colony in Chennai) to the primary healthcare centre, 15 minutes away.

At the Centre, she puts on a white PPE, wears double gloves, two masks and a scrub cap; picks up testing kits and climbs into an ambulance, doubling as a sample collection vehicle. For the next eight hours, she goes around Sholinganallur zone in Chennai to draw nasal and throat swabs.

Sugitha’s mother wants her to quit fearing the deadly virus. “My mother asks me everyday how many samples I had collected,” Sugitha said. “I always underplay it.”

The 100-odd sample she collects is a small fraction in Tamil Nadu’s high testing numbers. On November 5, Tamil Nadu tested a total of 10 million people (10,052,393) in the state with more reliable RT PCR (Reverse transcription polymerase chain reaction) test, the only state in India to have done so till date. On November 1, it crossed the 10-million mark of the number of persons tested in all.

Uttar Pradesh has the highest testing count in India at 15.4 million, but only 5.8 million of these tests are of RT-PCR and about 8.8 million are of the less accurate rapid antigen tests. In tests per million, Delhi tops at 243,339 and Tamil Nadu is at 134,353. Antigen accounts for about 40% of the total tests in Delhi. Maharashtra’s per million tests is 74,664 and Uttar Pradesh’s 68,038.

Tamil Nadu has 736,777 cases which is the fourth highest in India. In July, the average daily cases peaked, but since October there is a downward trend in new positive cases. “We are searching for the virus and chasing it,” health minister C Vijayabhaskar has said often.

Tamil Nadu was able to achieve the fete because of better RT-PCR facilities and patient tracking system because of its past efforts in AIDS and H1N1 control. For Covid-19, the state health department just added surveillance and testing to the existing system.

One such measure was roping in laboratory technicians, like Sugitha who is trained to collect oral swabs to test for tuberculosis (TB). Sugitha joined the corporation in December 2019 under the National TB Elimination Project. She was brought into the Covid-19 workforce in April.

The network is brought together like a well-oiled machine by door-to-door enumeration, fever camps and home quarantine and isolation monitoring system (HQIMS). “The state provided 100-crore for strengthening our home surveys and HQIMS,” said Greater Chennai Municipal Corporation commissioner G Prakash.

Covid detection starts with the fever surveyors like J Sivalingadurai (the corporation’s paid volunteer since April 16) going door-to-door. Each surveyor is assigned 150 homes. Sivalingadurai’s assigned families are in a posh multi-storey apartment on Old Mahabalipuram Road in south Chennai, where techies from across India and abroad live. He visits each home daily and asks the same set of questions: “How are you feeling today? Do you have a fever? Can you smell?”

His intrusion is crucial in identifying a host of the virus. “Bro!” one woman techie exclaimed in relief as soon as she saw him at her door on June 26 morning. “Check our temperatures,” she had told him. The woman in her mid-20s and her two roommates had developed fever the previous night. Since they had popped paracetomols, the thermal scanner showed no fever. “If they hadn’t told me about their fever, I wouldn’t have known,” said Sivalingadurai, adding going every day helps in building trust.

The woman techie was sent to a fever camp. She tested positive and moved to a quarantine facility. Her roommates turned negative but were put on home quarantine. Fever camps became a crucial link in virus control measures. So far, 3,378,398 people have attended the camps in Chennai with 15% positive rate.

The fever camps have been increased to 550 in Chennai from 300 in May. “We replicated Chennai’s model, particularly the fever camps in Madurai and it worked in reducing the virus spread,” said health secretary J Radhakrishnan.

Doctors at the fever camps or sanitary inspectors call sample collectors like Sugitha to specific locations. Once a technician draws a swab, they transfer it to a tube packed in vaccine carrier for the civic staff in the evening to carry them to the King Institute of Preventive Medicine and Research, the first testing lab approved by the Indian Council of Medical Research for Covid-19 testing in Tamil Nadu. The state now has 203 government and private testing facilities.

As the cases have increased, testing at labs has risen by almost 20 times. At a Chennai private lab, the lead microbiologist, who did not wish to be named, started by testing 50 samples a day in mid-April which increased to 800 in July and now she tests around a 1,000 samples.

“In the early days, I used to say a prayer for every patient’s sample tube I held,” she said. “Now we have reached a saturation point, we feel neutral.” Inside the bio-safety cabinet, she opens the sample vial for extraction and loads it into the RT-PCR machine. It takes 45 minutes to process a batch of 12 samples. Microbiologists work in three shifts to keep testing 24×7 at this lab. The final step in the testing process is the (PCR) machine detecting if the specific SARS-CoV-2 genome is present in the sample (if the detected patient is positive). It takes between 24 to 48 hours before a patient receives their result.

If the report is positive, a sanitary inspector (SI) inspects the patient’s home to certify if they have a separate room and toilet for home quarantine. The SI also starts contact tracing to isolate potential virus carriers. “In emergency situations or if patients are in the vulnerable category, I call the zonal officer to check availability of beds and send them directly to the hospital in an ambulance,” says SI of Chennai’s Sholinganallur zone, S Nayanaprakasan, who also coordinates amongst patients, their families, field workers like Sugitha, Sivalingadurai as well as senior officials of GCC. “We peaked in July when I was seeing at least 25 cases a day and now in October we are seeing only one or two cases per day,” he says, about his division.

“Because of these structural methods, there has been no outbreak or spurt in Chennai in the recent months,” said civic chief Prakash.



Source link