Potential raspberry problem (virus ?)

Hello all,

I was hoping you could advise me.
Two of my raspberry plants (one bought as a plant last year, the second as a bare root this year) have developed brown marks on their leaves.
Plant 1 is most severe and I have already cut off 10-20 leaves over the last month.
Plant 2 is less severe, but has marks on a couple of leaves.

Does anyone know what these may be and if there is anything that can be done?

I’m hoping I don’t have to rip them up, but will if I have to.

I’m wondering whether I they should be
put in isolation for the time being in case it’s infectious?

photos attached.

Any advice would be most welcome.