Evaluation of Whatman FTA cards for the preservation of yellow fever virus RNA for use in molecular diagnostics
Fig 2
YFV spiked into serum can be extracted from FTA cards but with lower sensitivity than traditional methods.
RNA from the vaccine strain of YFV, 17D-204, was extracted using the manufacturers protocol from 140 μL of YFV diluted in serum, from a single FTA punch, and from two FTA punches. The dotted line at Ct value 37 indicates the cut-off for YFV RNA positivity and is based on cutoffs used in the molecular diagnosis of YFV in the field. Dilution to make the standard curve were performed in human, flavivirus negative serum. Points represent the average of two experiments and were fit using a linear regression.