RVFV Detection in Sera and Tissues

The collected blood sera (100 µL) were directly mixed with 400 µL of AVL buffer from the QIAmp Viral RNA kit (Qiagen, Courtaboeuf, France). The whole brain and liver of euthanized mice were weighed and homogenized in a 500 µL DMEM using Tissue Lyser II (Qiagen). The viral RNAs were purified using the QIAmp Viral RNA kit (Qiagen) following the manufacturer’s protocol. The detection of the RVFV M segment was conducted by RT-qPCR using the SuperScript III Platinum One-Step qRT-PCR kit (Thermo Fisher Scientific, Villebon-sur-Yvette, France), as described elsewhere [35 (link),36 (link)]. The efficiencies were estimated from the standard curves based on ten-fold dilutions of each viral stock, and were used to convert the Ct values to PFU-per-milliliter equivalents (eqPFU/mL) for the sera, or PFU-per-gram equivalents (eqPFU/g) for the tissues. Wilcoxon–Mann–Whitney test analyses were conducted using R software.