Keywords
pools
rt PCR
boiling
optimization
How to Cite
Abstract
Introduction: In March 2020, the WHO declared the SARS-CoV-2 pandemic, with real-time PCR (rt-PCR) being the gold standard for its diagnosis. Given the excessive demand for reagents and their lack, alternatives were tested to optimize them. Objective: To compare methods that allow optimizing resources in the diagnosis of SARS-CoV-2: nucleic acid extraction by the traditional method versus heat inactivation (boiling) and individual processing versus performing sample mixtures (pooling). Materials and methods: Nasopharyngeal swabs in transport medium for viruses or in RNase-free water were used for the comparison. Nucleic acids were extracted and purified by columns. Samples were inactivated by heating (boiling). Sample pools were obtained according to the matrix pool strategy. Results: No significant differences in Ct were observed in samples inactivated by boiling or in sample pools, respect to the results obtained by the traditional procedure. Discussion: The adoption of these strategies allowed optimizing extraction resources and time in the diagnosis of SARS-CoV-2. The realization of pools in matrix format could be applied in populations with low prevalence of infection, whereas inactivation by boiling could be used in times of high prevalence.
References
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