Nucleic acid extraction
Viral RNA was extracted from 200 uL of each specimen using Roche High
Pure Viral RNA (Roche Applied Sciences, Manheim, Germany) kit based on
manufacturer’s instructions.. RNA were eluted in 50 μL of elution buffer
and were stored at -20oC prior to RSV screening [9]. cDNA was
synthesized using primed viral RNA, 5x first strand buffer, 10mM DTT,
one unit of RNAseOUT and five units of M-MLV RT (Moloney Murine Leukemia
Virus Reverse Transcriptase ) (Invitrogen, Carlsbad, CA, USA) for
genotype identification.