Introduction: The world witnessed a pandemic in the form of Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2) beginning in late 2019 initiating from the focus of wet markets in China. The infection got rapidly transmitted via droplets/aerosols & contact with respiratory secretions, leading to the development of mild/moderate/severe pneumonia. Although only 15-20 % of infections were of a moderate/ severe nature, they were sufficient to overwhelm the healthcare system of any country. Early detection of COVID-19 infection was of utmost importance to ensure timely isolation of positive cases to contain transmission in community settings. Therefore development and continued evaluation of the performance of the point-of-care tests were essential. for the purpose. Aim: To compare the diagnostic performance& usefulness of StandardTM Q COVID-19 Ag kit (SD Biosensor®, Republic of Korea) (index test) against TrueNat RTPCR (Molbio Diagnostics, India) which is a modified RTPCR (reference test) and approved by ICMR, in early detection of COVID cases so that early treatment can be instituted and prompt isolation of Covid positive patients can be done. Material & Methods: This study was carried out in the molecular biology laboratory of the Department of Microbiology, Noida International Institute of Medical Sciences, Greater Noida between April 2021 and September 2021. Sixty-two nasopharyngeal specimens from patients clinically suspected of having COVID-19attending OPD and admitted to wards of NIIMS hospital were tested both by COVID-19 lateral flow assay and TrueNat RTPCR assay simultaneously. Results of specimens tested with either COVID lateral flow assay or TrueNat RTPCR alone were excluded. The data were analyzed statistically. Result: SARS CoV2 was detected in 8 specimens by RT PCR assay and in 5 specimens by lateral flow assay, all 5 being positive by RT PCR assay. The sensitivity of rapid antigen detection lateral flow assay was 62.5% while the specificity was 100% at a 95% confidence interval. The positive predictive value was 100% and the negative predictive value was 94.7%. Conclusion: Our study indicated that STANDARDTM Q COVID-19 Ag Test (SBIOSENSOR) is a useful test having high specificity and moderate sensitivity which can be used as a screening test for rapidly identifying positive patients in community settings. However, for the detection of all positive Covid patients, RTPCR should be used wherever feasible.
