I too work on picornaviruses. We have a lab protocol for extracting vRNA
from infected cell lysates:
acid phenol (selects against DNA)
EtOH ppt. for 60'
The resulatant vRNA works well for RT-PCR. Hope this is of some help and
that you don't mind phenol (I wasn't sure)
Lee R. Martin
LRM at zeus.ahabs.wisc.edu