Assessment of Lysenow® Perforated Card on Preservation of Dengue Virus RNA in Whole Blood

Degradation of RNA in clinical specimens during storage and transportation is a major problem in accurate diagnosis of RNA virus infection. Concerns on degradation of RNA made cold-chain a necessity during transportation/storage of specimens for downstream molecular applications. However, cold-chain is not only costly but also can be scarce or compromised by insufficient supporting infrastructure or staff in resource-constrained settings. In this study, we employed dengue virus serotype-1 (DENV-1), an RNA virus, to test the performance of LyseNow® Perforated Card with commonly used Whatman FTA™ Micro Card in RNA preservation of the DENV-1 spiked in human whole blood, at different time points up to 109 days, stored at both room temperature and 37oC. There were a 35-fold and 800-fold reduction of DENV-1 RNA from the LyseNow® Perforated Card and Whatman FTA™ Micro Card, as compared to the un-loaded spiked whole blood. Once dried on the cards, the DENV-1 RNA remained stable on the LyseNow® Perforated Card stored at both room temperature and 37oC up to the end of the study of Day 109. On the other hand, the DENV-1 RNA recovered from spiked whole blood spotted on the FTA™ Micro Card showed additional 8-fold and 20-fold reduction in RNA after stored at room temperature and 37oC for 109 days, respectively. Our results showed LyseNow® Perforated Card had superior ability in preserving DENV-1 RNA during prolonged storage even an elevated temperature of 37oC.

Keywords: paper-based card, RNA preservation, Dengue virus, whole blood