Whole genome sequencing of respiratory syncytial (RSV) virus from clinical samples with low viral load

Abstract

Here is a description of a protocol for whole genome sequencing of RSV from clinical samples (nasopharyngeal aspirates -NPA-). The protocol was tested with samples with viral loads as low as 10+03 viral copies/ml NPA. The RNA is amplified by RT-PCR in five overlapped fragments of around 2300-4500 nt in length by using specific primers which anneal in conserved regions of the genome. Briefly the protocol includes: viral RNA extraction from NPA done with silica membrane columns and fragment amplification performed in five independent reaction tubes with OneStep RT-PCR Kit (Qiagen). Each fragment size check performed in an agarose gel electrophoresis, clean-up step done with silica membrane columns and the quantification step performed by Qubit. Finally, amplicons pooled equimolarly and library prep done with Nextera XT Kit.