FIG. 6.

Detection of HAV in various matrices. For panel A, waste water was sampled at different stages during the municipal treatment process and spiked with HAV to a final concentration of 10⁶ PFU/ml. Five microliters of sample was subjected to the NASBA and dot blot hybridization procedure as described in Materials and Methods. (A) 1, spiked Rnase-free water (positive control); 2, spiked raw waste water; 3, spiked waste water after aerobic digestion before UV treatment; 4, spiked waste water after aerobic digestion and UV treatment; 5, negative control (unspiked waste water sample). For panel B, lettuce and blueberry samples were inoculated as described in Material and Methods using HAV-spiked water. Attached viruses were eluted, and 5 μl of the eluate was subjected to the NASBA and dot blot hybridization procedure. 1, signal obtained using eluate from spiked lettuce; 2, signal obtained using eluate from spiked blueberries. In this case, the negative controls consisted of eluates from lettuce and blueberries treated with uncontaminated water (data not presented).