FIG. 1.

Sensitivity of the real-time NASBA assay. (A) Detection of serial dilutions of HAV viral RNA at 1,000, 100, 0, and 1 PFU per reaction. A negative control containing only water was used for comparison. (B) Standard curve generated by plotting the time required for signal detection versus PFU. Fluorescence intensity data were recorded every minute of the NASBA reaction. The threshold cycle of each amplification reaction was calculated based on the first cycle at which the fluorescence was 10-fold higher than the standard deviation of the mean baseline emission. The data represent the results from four independent experiments.