ok, thanks for the links.

However, that Defra link, whilst describing the problem, doesn't actually say how to fix it! The vine, looking at it, has been in place, acting as a screen around the pool for some years, they drastically cut it back to the ground last year (don't know if this infection happened last year as well or not). But its a big vine anyway.

Any recommendations for treatment, or is it a death sentence for the vine?