Evaluation of sample pooling method for SARS CoV-2 RNA detection; a laboratory based simulated study

Real time RT-PCR is considered as the gold standard test to detect COVID-19. The use of sample pooling strategy increases testing capacity and spares resources. However, the effectiveness of sample pooling should be evaluated in the setting before being implemented. Forty five samples including 20 high positives (Ct<20), 20 low positives (Ct 20-40) and 05 negative samples were used to prepare 1:1, 1:3 and 1:5 simulated sample pools which were then subjected to viral RNA extraction followed by real time RT-PCR. Sensitivity and specificity of sample pooling technique in the detection of SARS-CoV-2 RNA was 100% without significant variation of Ct values. According to our results, pooling of up to 6 samples will not have an effect on the final result in clinical samples and hence can be adopted in the given context for the diagnosis of COVID-19 by RT-PCR.