I don't know how many times I lived to regret leaving a potentially virused lily "just to wait and see". The last time was a few years ago when a yellow henryi showed very strong symptoms. It's hard to find new bulbs of these so I left it. Ended up removing several Griesbach bulbs from the Big Dig. I was not happy about that, those bulbs were not replaceable.
A regular dose of round up will quickly kill lilies. I used it on a virused Pink Dragonfly (LA I believe) lily back in 2015. I figured the virus would not continue living in the dead tissue. It pretty much melted down by a day or two later. Didn't have to touch it or use my pruners.
