Stability of HCV, HIV-1 and HBV nucleic acids in plasma samples under long-term storage.

The implementation of nucleic acid amplification technology (NAT) for detection of HCV, HIV-1 and HBV has undoubtedly contributed to the viral safety of blood, reducing the window period. One important matter related to the stability of RNA/DNA is the effect of the storage conditions on samples. In a previous work, we studied the stability of HCV RNA in plasma samples after storage at different temperatures. This work is an update on the follow-up of a sample containing 100 IU/ml HCV RNA for 5 years at -20 degrees C, showing no decrease in the initial titre. The nucleic acid stability of other viruses, such as HIV-1 and HBV, has also been studied. At -20 degrees C, samples containing HIV-1 were followed up for approximately 3 years and the results obtained show no decay in HIV-1 RNA detectability. Regardless of the HIV-1 RNA concentration, samples stored at 5 degrees C maintain their titre for at least 14 days. At 25 degrees C, the HIV-1 RNA half-life was determined at nearly 7 days. The HBV DNA, at 5 degrees C and 25 degrees C, is stable for at least 28 days, regardless of the initial titre.