Method for detection of viral rna

There is disclosed a process for detecting an RNA virus in a tissue cell or fluid sample, e.g. clinical, suspected of containing the virus. The process comprises heating the sample to a temperature sufficient for protein uncoating the RNA virus, in the presence of an RNase enzyme inhibitor active at said temperature, such as diethylpyrocarbonate (DEPC). Uncoated RNA is preferably further protected from destructive RNase activity upon cooling of the sample by addition of a proteinaceous RNase inhibitor, such as RNadeTM or RNasinTM, when the temperature of the sample is below the denaturation temperature for the inhibitor. RNA can then be detected, for example by reverse transcription (RT) to form cDNA and then applying the polymerase chain reaction (PCR) method to amplify the amount of cDNA to detectable levels. Detection of cDNA so amplified confirms the presence of RNA virus in the initial clinical sample.