ICMR scientist approves of pooling five COVID-19 samples for RT-PCR testing

A recent Indian Council of Medical Research (ICMR) study has revealed that pooling five samples to detect coronavirus by RT-PCR testing is an acceptable strategy without much loss of sensitivity, even for low viral loads, but with 10-sample pools there remains a higher chance of false negatives.

As per reports, the ICMR study was conducted to draw a comparative analysis of pooled testing for 5- and 10-sample pools by RT-PCR at ten different labs conducting COVID-19 testing across the country. 

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Labs flooded with samples

The results of the study have now been published in the latest edition of the Indian Journal of Medical Research (IJMR). Dr Nivedita Gupta, a scientist at ICMR and lead author of the study, said that the labs are flooded with huge sample loads for the COVID-19 test. 

Dr. Gupta said, "The high sensitivity of optimized real-time RT-PCR assays makes pooled testing a potentially efficient strategy for resource utilization when positivity rates for particular regions or groups of individuals are low. We conducted a comparative analysis of pooled testing for 5- and 10-sample pools by real-time RT-PCR across 10 COVID-19 testing laboratories in India." 

"At each laboratory, 100 nasopharyngeal swab samples including 10 positive samples were used to create 5- and 10-sample pools with one positive sample in each pool. RNA extraction and real-time RT-PCR for SARS-CoV-2-specific E gene targets were performed for individual positive samples as well as pooled samples", she added. 

The Indian Council of Medical Research (ICMR) issued new guidelines on Friday allowing on-demand testing for the COVID-19. As per the advisory, individuals who wish to get tested and are travelling to countries or the Indian States which require a mandate negative COVID-19 test at the entry can get the test done easily. 

India's total COVID-19 cases stand at 40,23,180 of which 8,46,395 are active while 31,07,224 people have recovered and 69,561 people have died, as per the latest Ministry of Health and Family Welfare data. 

(With ANI inputs)

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