The failure of draft sequencing for Marburg at 3· to 6· coverage or of simulated variola draft with a high error rate to facilitate the prediction of detection signatures highlights a need for finished viral sequences, or at least for draft of high quality such as 8·. Otherwise, a large number of signature candidates either will fail in screening because they are incorrectly designated as conserved among strains (as observed with the Marburg results), or too few regions will be classified as conserved (as observed with variola), and thus not be considered for signatures.