SARS-CoV-2 Viral RNA Detection via qPCR

qPCR was performed on RNA extracted from swabs collected immediately prior to euthanasia using QiaAmp Viral RNA mini kit (Qiagen, Germantown, MD, USA) according to the manufacturer’s instructions. Tissues (30 mg or less) were homogenized in RLT buffer and RNA was extracted using the RNeasy kit (Qiagen, Germantown, MD, USA) according to the manufacturer protocol. Viral RNA was detected with a one-step real-time RT-PCR assay (Quantifast, Qiagen, Germantown, MD, USA) using primers and probes generated to amplify the E gene and with custom primers designed against the SARS-CoV-2 E protein as previously described [16 (link),17 (link)].