Evaluation of HDV stability under different biological sample collection and storage conditions: implications for molecular diagnosis

In Brazil, the Amazon region has the highest rate of infection by the hepatitis Delta virus, and owing to regional difficulties in transporting and storing samples, especially in remote regions and isolated populations, the expansion of molecular diagnosis has become a significant public health problem. This study aims to analyze the stability of HDV under different temperature and storage conditions, providing essential information for the expansion of the molecular diagnosis of Hepatitis Delta. Whole blood, serum, and plasma samples were collected from chronic HDV patients. The samples were subjected to different temperatures and storage conditions, and HDV-RNA detection was performed via RT-qPCR. HDV was stable under various temperature conditions, including high temperatures, with minimal variations in Ct values. Compared with cryopreserved samples, DBS samples presented greater variation. The results suggest that HDV can remain detectable for up to 96 h when stored at room temperature, 4 °C, -30 °C, and - 80 °C and for up to 72 h at temperatures ranging from 4 °C to 42 °C, in addition to the possibility of detection via filter paper, although with reduced sensitivity. HDV is stable under different conditions, which is crucial for molecular diagnostics in regions with adverse storage conditions.