On one hand, if this virus was deadly to dart frogs, I'm sure we would have heard of mass losses of collections by now. As I stated above, because RV is not routinely tested for, we don't know for certain that it's not in most collections and only causing minor illness, if any.
On the other hand, if we are dealing with a virulent virus that has a high mortality rate, I don't think we are prepared to manage it. I don't know much about RA. It could be very fragile outside its host and only live a matter of minutes or hours outside the host, or it could be like hepatitis or flu viruses that can stay viable for days or weeks on inert surfaces. The implications of this would likely be catastrophic if the virus is deadly to most dart frogs because everything brought into proximity to the frogs, including feeders/cultures, plants, substrate, rocks, wood, cork bark, clay, etc. could be carrying viable viruses. I don't know what temperatures RV can survived under, but some viruses cannot be destroyed at the boiling point of water. Therefore, we'd be faced with chemical sterilization or autoclaving. Obviously nothing living could be placed in the viv and swab testing a plant or feeder culture might miss it given the large surface area.
I strongly suspect that if scenario 2 above was the case, we would have seen it by now. If we are dealing with a virus that causes only mild infection, then the frogs will fight it off and without additional hosts, the viruses in that viv would likely die off over time, so Glenn, I see no reason to kill the frogs that have tested positive.
Also Glenn - how long have the viruses persisted in a given viv, if you have that information? My guess is that after infecting all the frogs in the viv, with no new addition of viruses, they would test negative after several weeks to months.