Hi folks, and thanks for your responses. I called my haematology department today and they advised that it is ok for my wife to have the zostavax shingles vaccine containing the live virus and that it does not pose a risk to me.
I'm not sure if the NHS currently allows shingrix (non-live virus) in the UK, but my CCG doesn't support it. I cross the magic 70 threshold next year so we will see what happens then, when I will need to have the jab myself.
Once again, thanks for your replies and support
John