Time and cost of RT-PCR to be reduced by omitting RNA extraction: ICMR
This new method reduced the overall test turnaround time by two hours. While the overall sensitivity of the new method was 78.9%
In a move to cut down testing time and cost, researches from Indian Council of Medical Research have evaluated a new and a simplified method of conducting RT-PCR tests by omitting the extraction of virus’s RNA before the test is conducted, thereby simplifying sample purification and reducing test time to detect Sars-Cov-2, according to a report in The Times of India. Extraction of RNA before the RT-PCR testing was a major bottleneck as it was time consuming and expensive. It also required trained human resources.
Earlier there were suggestions that the test could be done by omitting RNA extraction from dry swab samples and subjecting them to methods like a buffer treatment for 30 minutes and heat inactivation for six minutes at 98 degree celsius.
By enrolling 1138 clininc attendees from two independent study sites in Pune and Kolkata, (ICMR-National Aids Research Institute, ICMR-NARI, Pune and School of Tropical Medicine (STM), Kolkata) researchers evaluated the performance of this alternative method.
This new method reduced the overall test turnaround time by two hours. While the overall sensitivity of the new method was 78.9%.
Caution to be exercised while using the new method
With the increasing number of Covid tests, the alternative protocol with shortened time has the potential to address the shortage of RNA extraction kits, when the demand for it was high.
However, care should be taken while choosing the right primer probe set and heat treatment approach while employing this method, the publication said.
It also added that a wrong approach might affect the sensitivity of the testing method. Thus, not all laboratories can opt for this method.