6533b82efe1ef96bd1292a2c

RESEARCH PRODUCT

Pooling of Nasopharyngeal Swab Specimens for SARS-CoV-2 detection by RT-PCR

David NavarroIgnacio TorresEliseo Albert

subject

Real-time polymerase chain reactionCoronavirus disease 2019 (COVID-19)Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)PoolingLarge populationBiologyVirologyContact tracingCase identificationSystematic testing

description

ABSTRACTSystematic testing of large population groups by RT-PCR is mandatory to Covid-19 case identification and contact tracing in order to minimize the likelyhood of resurgence in contagion. Sample pooling for RT-PCR has been effectively used to detect community transmission of SARS CoV-2. Nevertheless, this procedure may decrease the sensitivity of RT-PCR assays due to specimen dilution. We evaluated the efficacy of this strategy for diagnosis of Covid-19 using a sensitive commercially-available RT-PCR targeting SARS CoV-2 E and RdRp genes in a single reaction. A total of 20 mini-pools containing either 5 (n=10) or 10 (n=10) nasopharyngeal exudates collected in universal transport medium were made, each of which including a unique positive NP specimen. Positive specimens yielding CT <32 for the E gene (6 out of 10) or <35.2 for the RdRP gene (7 out of 10) were detected in mini-pools of both sizes. In contrast, most NP samples displaying CTs > 35.8 for the E gene or 35.7 for the RdRP gene remained undetected in mini-pools of 5 specimens (3/4 and 2/3, respectively) or in mini-pools of 10 samples (4/4 and 3/3, respectively.

yearjournalcountryeditionlanguage
2020-04-25
https://doi.org/10.1101/2020.04.22.20075598